DE112008002258T5 - Hydraulic fluid composition and its preparation - Google Patents

Abstract

A hydraulic fluid composition comprising (i) 80 to 99.999% by weight of a base lubricating oil and (ii) 0.001 to 20% by weight of at least one additive package, wherein
the base lubricating oil has consecutive numbers of carbon atoms, less than 10% by weight of naphthenic carbon according to ndM, less than 0.10% by weight of olefins and less than 0.05% by weight of aromatics, more than 25% by weight all molecules having cycloparaffin functionality and a ratio of molecules having monocycloparaffin functionality to molecules having multicycloparaffin functionality greater than 10; and
wherein the hydraulic fluid composition meets at least one of the JCMAS HK and JCMAS HKB 2005 standard specifications.

Description

TECHNICAL AREA

The This invention relates generally to hydraulic fluid compositions and, more specifically, hydraulic fluid compositions with excellent Oxidation resistance.

BACKGROUND

hydraulic fluids serve as a power transmission medium in a hydraulic System. They are designed in such a way that they force and move in industrial, mobile and non-mobile hydraulic systems, as in automobiles, tractors, bulldozers, construction machinery and hydraulic pumps etc. For a special, newer application, hydraulic systems in construction machines, for example, a higher pressure is added spent smaller hydraulic pumps and engines, so that the performance of the system is increased. The smaller capacity of the reservoir for hydraulic fluid and lower ventilation on the machine or pump room due of noise protection speeds up the oxidation and the thermal Degradation of hydraulic fluids. The Technical Committee for fuels and lubricants of Japan Construction Mechanization Association (JCMA) has the terms JCMAS HK and JCMAS HKB specifications for hydraulic fluids (biological degradable hydraulic fluids) created in mobile construction equipment should be used.

Most hydraulic oils are made from mineral oil. In applications where oil can enter the environment, the base oil used is often environmentally friendly ester oils, for example based on rapeseed oil and / or soybean oil. In recent years, an alternative base oil source has been disclosed in a number of patent publications and applications, ie US 2006/0289337 . US2006 / 0201851 . US2006 / 0016721 . US2006 / 0016724 . US2006 / 0076267 . US2006 / 020185 . US2006 / 013210 . US2005 / 0241990 . US2005 / 0077208 . US2005 / 0139513 . US2005 / 0139514 . US2005 / 0133409 . US2005 / 0133407 . US2005 / 0261147 . US2005 / 0261146 . US2005 / 0261145 . US2004 / 0159582 . US7018525 . US7083713 U.S. Serial Nos. 11/400570, 11/535165 and 11/613936, which are incorporated herein by reference. The references disclose a Fischer-Tropsch base oil made in a process wherein the feed is a waxy feed recovered from a Fischer-Tropsch synthesis. The process comprises a step of fully or partially dewaxing by hydroisomerization using a double-acting catalyst or catalyst capable of selectively isomerizing paraffins. Dewaxing by hydroisomerization is accomplished by bringing together the waxy feed with a hydroisomerization catalyst in an isomerization zone under hydroisomerization conditions. The products from the Fischer-Tropsch synthesis can also be obtained by known methods, such. For example, by the commercial SASOL ^® -Aufschlämmungsphase-Fischer-Tropsch technology, the commercial SHELL ^® available -Mitteldestillat-Synthesis (SMDS) process or not obtainable by the commercially EXXON ^® -Advanced Gas Conversion (AGC -21-) method.

It There is still a need for a hydraulic fluid, in particular a functional fluid that meets the specifications of Japan Construction Mechanization Association meets, which is an excellent Has oxidation resistance and alternative hydrocarbon products starts.

SUMMARY OF THE INVENTION

In One embodiment is a hydraulic fluid composition prepared comprising (i) a base lubricating oil comprising comprising: consecutive numbers of carbon atoms, less as 10% by weight of naphthenic carbon according to n-d-M, less than 0.10 weight percent olefins and less than 0.05 weight percent aromatics; (ii) 0.001-20% by weight of at least one additive package; wherein the hydraulic fluid composition meets at least one of the JCMAS HK and JCMAS HKB standard specifications.

Under another aspect is provided to a method for reducing the oxidative degradation of hydraulic fluids used in construction machinery be used, the method using a Hydraulic fluid composition comprising a base lubricating oil, comprising: consecutive numbers of carbon atoms, less than 10% by weight of naphthenic carbon according to n-d-M, less than 0.10 weight percent olefins and less than 0.05 weight percent aromatics; (ii) 0.001-20% by weight of at least one additive package; in which the hydraulic fluid composition at least one of the JCMAS HK and JCMAS HKB standard specifications met.

BRIEF DESCRIPTION OF THE DRAWINGS

It shows:

1 Fig. 3 is a graph comparing the variation in kinematic viscosity at 40 ° C of a prior art hydraulic fluid and one embodiment of the hydraulic fluid of the invention in a piston pump test;

2 Figure 12 is a graph comparing the change in acid number of a prior art hydraulic fluid and one embodiment of the hydraulic fluid of the invention in a piston pump test.

DETAILED DESCRIPTION

The The following terms are used throughout the description and have the following meanings, unless stated otherwise.

As used here, "hydraulic fluid" is interchangeable used with "functional fluid", which means Fluid is called that for transfer of energy in industrial applications as well as in mobile and non-mobile vehicles and equipment as a lubricant, Hydraulic fluid, automatic transmission oil (Automatic Transmission Fluid), heat exchange medium or the like becomes.

"Out a Fischer-Tropsch process "means that the product, the fraction or the charge from a stage of a Fischer-Tropsch process originates or is produced there. As Used here, "Fischer Tropsch Base Oil" can be interchangeable can be used with "FT base oil", "FTBO", "GTL Base oil "(GTL: gas-to-liquid) or" off a base oil derived from a Fischer-Tropsch process ".

As used herein is "isomerized base oil" for a base oil obtained by isomerization of a waxy Charge is received.

As As used herein, a "waxy feed" includes at least 40% by weight of n-paraffins. In one embodiment the waxy feed more than 50% by weight of n-paraffins. In a another embodiment comprises the waxy feed more than 75% by weight of n-paraffins. In one embodiment In addition, the waxy feed contains very small amounts Nitrogen and sulfur, for example less than 25 in total ppm of nitrogen and sulfur together or less in other embodiments as 20 ppm. Examples of waxy feeds include Slack wax, de-oiled slack wax, refined after-oils, Wax lubricant raffinates, n-paraffin waxes, NAO waxes, in Chemical plant made waxes, from de-oiled Petroleum derived waxes, microcrystalline waxes, Fischer-Tropsch waxes and mixtures thereof. In one embodiment, the waxy feeds a pour point above 50 ° C. In another embodiment, it is larger 60 ° C.

As used herein, "pour point reducing blending component" refers to an isomerized wax product having relatively high molecular weights and a fixed degree of alkyl branching in the molecule such that it lowers the pour point of base lubricating oil blends containing them. Examples of pour point reducing blending components are disclosed in U.S. Patent Nos. 4,178,074; U.S. Patents 6,150,577 and 7,053,254 and in the patent publication US 2005-0247600 A1 , A pour point reducing blending component may be: 1) an isomerized bottom product derived from a Fischer-Tropsch process; 2) a bottoms product made from an isomerized, highly waxy mineral oil, or 3) an isomerized oil having a kinematic viscosity at 100 ° C of at least about 8 mm ² / s, made from polyethylene plastic.

As used herein, the "10 percent point" in the boiling range of a pour point reducing blend component refers to the temperature at which 10 percent by weight of the hydrocarbons present in that fraction evaporates at atmospheric pressure. Similarly, the 90 percent point in the respective boiling ranges refers to the temperature at which 90 percent by weight of the hydrocarbons present in this fraction evaporate at atmospheric pressure. For samples boiling above 1000 ° F (538 ° C), the boiling range can be determined using the Standard Analysis Method D-6352-04 or one equivalent. For samples with a boiling range below 1000 ° F (538 ° C), the boiling range distributions in this disclosure may be calculated using the Standard Analysis Method D-2887-06 or one equivalent. It will be appreciated that only the 10 percent point of the particular boiling range is used when referring to a pour point reducing mixing component that is a bottoms product of vacuum distillation is because it comes from a bottoms fraction, making the 90 percent point or the upper boiling point irrelevant.

"Kinematic viscosity" is a measurement of the flow resistance of a fluid under gravity in mm ² / s, determined by ASTM D445-06 ,

"Viscosity Index" (VI) is an empirical, unitless number that indicates the effect of a temperature change on the kinematic viscosity of the oil. The higher the VI of an oil, the lower its desire to change viscosity with temperature. The viscosity index is determined according to ASTM D 2270-04 measured.

The apparent viscosity in the cold-start simulator (CCS VIS) is a measurement in millipascal seconds, mPa · s, which measures the viscometric properties of base lubricating oils at low temperature and high shear. The CCS VIS is using ASTM D 5293-04 certainly.

The boiling range distribution of base oil in weight percent is determined by simulated distillation (SIMDIS) according to ASTM D 6352-04 , "Boiling Range Distribution of Petroleum Distillates in Boiling Range from 174 to 700 ° C by Gas Chromatography".

The "noack volatility" is defined as the mass of oil, expressed in weight percent, that is lost when the oil is heated at 250 ° C with a constant stream of air flowing through it for 60 min ASTM D5800-05 Method B is measured.

The Brookfield viscosity is used to determine the internal fluid friction of a lubricant during cold operation ASTM D 2983-04 can be measured.

"Pour point" is the measurement of a temperature at which a base oil sample begins to flow under certain carefully controlled conditions, according to ASTM D 5950-02 can be determined.

"Autoignition temperature" is the temperature at which a fluid ignites spontaneously on contact with air itself, according to ASTM 659-78 can be determined.

"Ln" stands for the natural logarithm base "e".

"Traction coefficient" is an indicator of intrinsic lubricant properties, expressed as the dimensionless ratio of frictional force F and normal force N, where friction is the mechanical force that opposes motion or inhibits movement between sliding or rolling surfaces. The traction coefficient can be measured with an MTM traction measuring system from PCS Instruments, Ltd., which consists of a polished ball with 19 mm diameter ( SAE AISI 52100 Steel) at an angle of 220 to a polished flat disc 46 mm in diameter ( SAE AISI 52100 Stole). Steel ball and disc are independently measured at a mean rolling speed of 3 m / s, 40% sliding rolling ratio and 20 Newton load. The rolling ratio is defined as the difference between the ball and the disc sliding speed divided by the average speed of the ball and the disc, ie rolling ratio = (Speed 1 - Speed 2) / ((Speed 1 + Speed 2) - / 2 ).

As used herein, "consecutive numbers of carbon atoms" means that the base oil contains hydrocarbon molecules whose number of carbon atoms is distributed over a range that also includes any number of carbon atoms between the specified limits. For example, the base oil may have hydrocarbon molecules ranging from C22 to C36 or from C30 to C60 with any number of carbon atoms in between. The hydrocarbon molecules of the base oil differ from each other by the consecutive number of carbon atoms, since the waxy feed also has consecutive numbers of carbon atoms. For example, in the Fischer-Tropsch hydrocarbon synthesis reaction, the source of carbon atoms is CO and the hydrocarbon molecules are built one carbon atom after another. Crude wax derived feeds have consecutive numbers of carbon atoms. Unlike a polyalphaolefin ("PAO") based oil, the molecules of an isomerized base oil have a more linear structure and include a relatively long framework with short branches. The classic textbook description of a PAO is a star-shaped molecule, and in particular tridecane, which is represented as three decane molecules joined together at a midpoint. Although a star-shaped molecule is theoretical, yet PAO molecules have fewer and longer branches than the hydrocarbon molecules that the isomerized Ba disclosed herein form sisoil.

"molecules with cycloparaffin functionality "stands for every molecule that is monocyclic or condensed is a multicyclic saturated hydrocarbon group or as one or more substituents.

"molecules with monocycloparaffin functionality "stands for every molecule that has a monocyclic saturated Hydrocarbon group having 3 to 7 ring carbon atoms, or for a molecule that uses a single monocyclic saturated hydrocarbon group with 3 to 7 ring carbon atoms is substituted.

"molecules with multicycloparaffin functionality "stands for every molecule that has a condensed multicyclic saturated Hydrocarbon ring group with two or more condensed Wrestling is, for every molecule, with one or the other several condensed multicyclic saturated hydrocarbon ring groups is substituted by two or more condensed rings, or every molecule that is saturated with more than one monocyclic Hydrocarbon group substituted with 3 to 7 ring carbon atoms is.

molecules with cycloparaffin functionality, molecules with Monocycloparaffin functionality and molecules with Multicycloparaffin functionality are in weight percent and are determined by a combination of field ionization mass spectroscopy (FIMS), HPLC-UV for aromatics and proton NMR for Olefins, which is fully described below.

Oxidizer BN measures the reaction of a lubricating oil in a simulated application. High values or long times for the adsorption of one liter of oxygen indicate good stability. Oxidator BN can be measured with an oxygen absorber according to Dornte ( RW Dornte "Oxidation of White Oils," Industrial and Engineering Chemistry, Vol. 28, page 26, 1936 ); under 1 atmosphere of pure oxygen at 340 ° F, the time to absorb 1000 ml of _O2 by 100 g of oil is obtained. In the oxidizer BN test, 0.8 ml of catalyst per 100 g of oil is used. The catalyst is a mixture of soluble metal naphthenates that simulates the average metal analysis of used engine casing oil. The additive package is 80 mmol zinc bispolypropylene phenyl dithiophosphate per 100 g oil.

Molecular characterizations can be performed by prior art techniques including field ionization mass spectrometry (FIMS) and ndM analysis ( ASTM D 3238-95 (Re-approved in 2005)). In the FIMS, the base oil is characterized as alkanes and molecules with different numbers of unsaturations. The molecules having different numbers of unsaturations may include, for example, cycloparaffins, olefins and aromatics. If aromatics are present in significant quantities, they are identified as 4-unsaturations. If olefins are present in significant amounts, they are identified as 1-unsaturations. The sum of the 1-unsaturates, 2-unsaturates, 3-unsaturates, 4-unsaturates, 5-unsaturations and 6-unsaturations from the FIMS analysis minus the weight percent olefins according to proton NMR and minus the weight percent aromatics according to HPLC-UV gives the Total percent by weight of molecules with cycloparaffin functionality. If the aromatics content was not measured, it was probably less than 0.1% by weight and was not included in the calculation of the total weight percent of molecules with cycloparaffin functionality. The total weight percent of molecules having cycloparaffin functionality is the sum of the weight percent of the molecules having monocycloparaffin functionality and the weight percent of the molecules having multicycloparaffin functionality.

The molecular weights are determined according to ASTM D2503-92 (Re-approved in 2002). The method uses the thermoelectric measurement of the vapor pressure (VPO). If the sample volume is insufficient, the alternative method of ASTM D2502-04 use; and if used, this is indicated.

The density will be according to ASTM D4052-96 (Re-approved in 2002). The sample is placed in an oscillating sample tube and the change in the oscillation frequency caused by the change in the mass of the tube is used along with the calibration data to determine the density of the sample.

The weight percent of olefins can be determined by proton NMR according to the steps given here. In most assays, the olefins are conventional olefins, ie, a distributed mixture of olefin types in which hydrogen atoms are attached to the carbon atoms of the double bond, such as: alpha, vinylidene, cis, trans and tri-substituted, with a detectable allyl to olefin-to-integral ratio between 1 and 2.5. If this ratio exceeds 3, it indicates a higher percentage of tri- or tetra-substituted olefins present, so that other assumptions known in the art of analysis can be made to calculate the number of double bonds in the sample. The steps are as follows: A) Prepare a solution of 5-10% test hydrocarbon in deuterochloroform. B) recording a normal proton spectrum of at least 12 ppm spectral width and accurately plotting the axis of chemical shift (ppm), the device having such a large gain range that a signal is obtained without overloading the receiver / ADC if, for example, a 30 ° pulse, the device has a minimum dynamic signal digitization range of 65,000. In one embodiment, the device has a dynamic range of at least 260000. C) measuring integral intensities between: 6.0-4.5 ppm (olefin); 2.2-1.9 ppm (allyl) and 1.9-0.5 ppm (saturated). D) using the molecular weight of the test substance according to ASTM D 2503-92 (Re-approved in 2002) to calculate: 1. the average molecular formula of the saturated hydrocarbons; 2. the average molecular formula of olefins; 3. the total integral intensity (= sum of all integral intensities); 4. the integral intensity per sample hydrogen (= total integral / number of hydrogen atoms in the formula); 5. the number of olefin hydrogen atoms (= olefin integral / integral per hydrogen); 6. the number of double bonds (= olefin-hydrogen × hydrogens in the olefin formula / 2); and 7. the weight percent olefins according to proton NMR = 100 × number of double bonds × number of hydrogen atoms in a conventional olefin molecule divided by the number of hydrogen atoms in a conventional test substance molecule. In this test, the calculation method D for the weight percent olefins by proton NMR works particularly well when the result for% olefins is low, ie, less than 15 wt%.

In In one embodiment, percent by weight of aromatics may HPLC-UV are measured. In one embodiment The test was performed on a Hewlett Packard 1050 Series Quaternary Gradient High Performance Liquid Chromatography (HPLC) System, coupled with an HP 1050 diode array UV-Vis detector attached to an HP Chem Station is connected. The identification of the individual Aromatic classes in the highly saturated base oil can be made on the basis of the UV spectral pattern and the elution time become. The amino-column used for this analysis distinguishes aromatic molecules mainly on the basis their ring number (or double bond number). Thus elute first followed by the molecules with a single aromatic ring of the polycyclic aromatics, in the order of increasing number of double bonds per molecule. At aromatics those with similar double bond character elute with only one alkyl substitution on the ring earlier than those with a naphthenic substitution. A clear identification the various aromatic hydrocarbons in the base oil based on their UV absorption spectra can be accomplished when you realize that their maximum electron transitions in comparison to the pure model compound analogues all shifted to red, and to an extent that from the amount of alkyl and naphthenic substitution on the ring system depends. A quantification of the eluting aromatic Compounds can be made by adding chromatograms Integrated wavelengths for each general Class of compounds via the appropriate retention time window have been optimized for this aromatic. The limits of the retention time window for each aromatic class be determined by the individual absorption spectra of the eluting Manually examined and set up connections at different times Based on their qualitative similarity to the absorption spectra associated with model compounds of the appropriate aromatics class become.

HPLC-UV Calibration. In one embodiment, HPLC-UV can be used for Identification of classes of aromatic compounds even at very low levels are used, for example, multi-ring aromatics absorb usually 10 to 200 times stronger than single ring aromatics. Alkyl substitution affects absorption 20%. The integration limits for the co-eluting 1-ring and 2-ring aromatics at 272 nm can be generated by the Perpendicular drop methods are set. Wavelength-dependent Reaction factors for each general aromatics class can be determined by first plots after Beer's Law of pure model compound mixtures based on the next spectral peak absorptions to the substituted aromatic analogues. The aromatics concentrations in percent by weight can be calculated by assuming that the average molecular weight for each aromatic class approximately equal to the average molecular weight for the entire base oil sample is.

NMR analysis. In one embodiment, the weight percent of all molecules having at least one aromatic function in the purified monoaromatic standard can be confirmed by long term carbon 13 NMR analysis. The NMR results can be deduced from the ratio of% aromatic carbon to% aromatic molecules (which must agree with HPLC-UV and D 2007), given that 95-99% of the aromatics in highly saturated base oils are single-ring aromatics are. In another test to accurately measure small amounts of all molecules with at least one aromatic function by NMR can (re-approved in 2004) Standard method D 5292-99 be modified so that a minimum carbon sensitivity of 500: 1 (according to ASTM standard practice E 386 ) was obtained with a 15 hour run on a 400-500 MHz NMR with a 10-12 mm Nalorac probe. Acorn PC integration software can be used to determine the shape of the baseline and for unified integration.

Extent of branching concerns the number of alkyl branches in hydrocarbons. The branching and branching position can be determined by carbon 13- ( ¹³ C) NMR according to the following new step procedure: 1) identify the CH branching centers and the CH ₃ branching endpoints using the DEPT pulse sequence ( Doddrell, DT; DT Pegg; MR Bendall, Journal of Magnetic Resonance 1982, 48, 323ff ). 2) Verification of the absence of carbon atoms that initiate multiple branches (quaternary carbon atoms) using the APT pulse sequence ( Patt, SL; JN Shoolery, Journal of Magnetic Resonance 1982, 46, 535ff. ). 3) Assign the various branch carbon resonances to specific branch positions and lengths using tabulated and calculated prior art values ( Lindeman, LP, Journal of Qualitative Analytical Chemistry 43, 1971 1245ff ; Netzel, DA, et al., Fuel, 60, 1981, 307ff ). 4) Estimate the relative branching density at various carbon positions by comparing the integrated intensity of the specific carbon of the methyl / alkyl group with the intensity of a single carbon atom (which is equal to the total integral / number of carbon atoms per molecule in the mixture). For the 2-methyl branch, where both the terminal and branch methyl are at the same resonance position, the intensity is divided by 2 before estimating the branching density. When the 4-methyl branching fraction is calculated and tabulated, its contribution to the 4+ methylene is subtracted so that a double count is bypassed, 5) calculating the average carbon number. The average carbon number is determined by dividing the molecular weight of the sample by 14 (the formula weight of CH ₂ ). 6) The number of branches per molecule is the sum of the branches determined in step 4. 7) The number of alkyl branches per 100 carbon atoms is calculated from the number of branches per molecule (step 6) x 100 / average carbon number. 8) Estimation of the branching index (BI) by ¹ H-NMR analysis, represented as percent of methyl hydrogen (range of chemical shift of 0.6-1.05 ppm) of total hydrogen as determined by NMR in the liquid hydrocarbon composition. 9) Branch branching (BP) estimation by ¹³ C NMR, represented as percent of repeating methylene carbon atoms - 4 or more carbon atoms away from the end group or a branch (by NMR signal) 29.9 ppm) - of the total carbon atoms as determined by NMR in the liquid hydrocarbon composition. The measurements can be made with any Fourier transform NMR spectrometer that has, for example, a 7.0 T magnet or more. After confirming that aromatic carbon atoms are absent by mass spectrometry, UV or NMR, the spectral width for the ¹³ C NMR studies can be restricted to the range of saturated carbon, 0-80 ppm, versus TMS (tetramethylsilane). Solutions of 25-50% by weight in chloroform-d1 are excited by 30 ° pulses, followed by a 1.3 second (s) recording time. In order to minimize non-uniform intensity data, broadband proton reverse gate decoupling is used during a delay of 6 seconds prior to the excitation pulse and further during acquisition. The samples are doped with 0.03 to 0.05 M Cr (acac) ₃ (tris (acetylacetonato) chromium (III)) as a relaxation agent, so that in any case complete intensities are observed. The DEPT and APT sequences can be performed as described in the literature with minor modifications described in the Varian or Bruker manuals. DEPT stands for Distortionless Enhancement by Polarization Transfer. The DEPT 45 sequence gives a signal of all carbon atoms bound to protons. DEPT 90 shows only CH carbon atoms. DEPT 135 shows CH and _CH3 ascending and _CH2 180 degrees out of phase (high to low). APT is the bound proton test known in the art. This allows one to see all the carbon atoms, but with increasing CH and CH ₃ , quaternary carbon atoms and CH _{2 are} descending. The branching properties of the sample can be determined by ¹³ C NMR, assuming in the calculations that the entire sample is isoparaffinic. The content of unsaturations can be measured by field ionization mass spectroscopy (FIMS).

In One embodiment includes the hydraulic fluid composition 0.001-20 wt% of optional additives in a base oil matrix or base oil admixtures in an amount of 80 to 99,999 Wt .-%, based on the total weight of the composition.

Base oil component: In one embodiment, the base oil matrix or mixtures thereof comprises at least one isomerized base oil, wherein the product itself, its fraction or the feed of the iso a waxy feed in a Fischer-Tropsch process or is prepared in one step ("Fischer-Tropsch derived base oils"). In another embodiment, the base oil comprises at least one isomerized base oil made from a substantially paraffinic wax feed ("waxy feed").

Base oils derived from the Fischer-Tropsch process are disclosed in a number of patent publications, such as US Pat U.S. Patents 6080301 . 6090989 and 6165949 and the US Patent Publications US2004 / 0079678A1 . US20050133409 . US20060289337 , The Fischer-Tropsch process is a catalyzed chemical reaction in which carbon monoxide and hydrogen are converted to liquid hydrocarbons of various forms, including a light reaction product and a waxy reaction product, both of which are substantially paraffinic.

In one embodiment, the isomerized base oil has consecutive numbers of carbon atoms and less than 10 weight percent naphthenic carbon according to ndM. In yet another embodiment, the isomerized base oil made from a waxy feed has a kinematic viscosity at 100 ° C between 1.5 and 3.5 mm ² / s.

In In one embodiment, the isomerized base oil is used Prepared by a process in which the dewaxing by Hydroisomerization carried out under such conditions that a base oil has: a) less than 0.30 wt .-% of all molecules with at least an aromatic functionality; b) more than 10% by weight all molecules having at least one cycloparaffin functionality; c) the ratio of the weight percent of the molecules with monocycloparaffin functionality to the weight percent of molecules with multicycloparaffin functionality is greater than 20 and d) the viscosity index is greater than 28 × Ln (kinematic viscosity at 100 ° C) + 80.

In another embodiment, the isomerized base oil is prepared in a process in which the high paraffin wax is reacted with a medium pore size, shape selective molecular sieve comprising a noble metal hydrogenation component and under conditions of 600-750 ° F (315-399 ° C). is hydroisomerized. In the process, the hydroisomerization conditions are controlled such that in the wax feed the conversion of the compounds boiling above 700 ° F (371 ° C) to compounds boiling below 700 ° F (371 ° C) is between 10 Wt .-% and 50 wt .-% is maintained. An isomerized base oil thus obtained has a kinematic viscosity between 1.0 and 3.5 mm ² / s at 100 ° C. and less than 50% by weight Noack volatility. The base oil comprises more than 3% by weight molecules with cycloparaffin functionality and less than 0.30% by weight aromatics.

In one embodiment, the isomerized base oil has a Noack volatility that is less than the amount that results from the equation: 1000 × (kinematic viscosity at 100 ° C.) ^-2.7 . In another embodiment, the isomerized base oil has a Noack volatility that is less than the amount that results from the equation: 900 × (kinematic viscosity at 100 ° C.) ^-2.8 . In a third embodiment, the isomerized base oil has a kinematic viscosity at 100 ° C of> 1.808 mm ² / s and a Noack volatility that is less than the amount that results from the equation: 1.286 + 20 (kv100) ^{-1 , 5} + 551.8 e ^-kv100 , where kv100 is the kinematic viscosity at 100 ° C. In a fourth embodiment, the isomerized base oil has a kinematic viscosity below 4.0 mm ² / s at 100 ° C and between 0 and 100% by weight Noack volatility. In a fifth embodiment, the isomerized base oil has a kinematic viscosity between 1.5 and 4.0 mm ² / s and a Noack volatility that is less than the Noack volatility, which is calculated by the equation: 160-40 (kinematic viscosity at 100 ° C).

In one embodiment, the isomerized base oil has a kinematic viscosity at 100 ° C in the range of 2.4 and 3.8 mm ² / s and a Noack volatility that is less than the amount defined by the following equation: 900 × (kinematic viscosity at 100 ° C) ^-2.8-15 ). For kinematic viscosities in the range of 2.4 and 3.8 mm ² / s, the equation gives: 900 x (Kinematic viscosity at 100 ° 0) ^-2.8 - 15) have a lower Noack volatility than the equation: 160-40 (kinematic viscosity at 100 ° C).

In one embodiment, the isomerized base oil is prepared in a process in which the highly paraffinic wax is hydroisomerized under such conditions that the base oil has a kinematic viscosity at 100 ° C of 3.6 to 4.2 mm ² / s, a viscosity index greater than 130 , less than 12% by weight Noack volatility and a pour point of less than -9 ° C.

In one embodiment, the isomerized base oil has an aniline point in ° F greater than 200 and less than or equal to an amount defined by the equation: 36 × Ln (kinematic viscosity at 100 ° C, in mm ² / s) + 200.

In one embodiment, the isomerized base oil has an autoignition temperature (AIT) that is greater than the AIT defined by the following equation: AIT in ° C = 1.6 × (kinematic viscosity at 40 ° C., in mm ² / s) + 300. In a second embodiment, the base oil has an AIT greater than 329 ° C and a viscosity index greater than 28 x Ln (kinematic viscosity at 100 ° C, in mm ² / s) + 100.

In one embodiment, the isomerized base oil has a comparatively small traction coefficient, more specifically, its traction coefficient is less than the amount calculated by the following equation: traction coefficient = 0.009 × Ln (kinematic viscosity in mm ² / s) - 0.001, the kinematic Viscosity in the equation is the kinematic viscosity during the measurement of the traction coefficient and is between 2 and 50 mm ² / s. In one embodiment, the isomerized base oil has a traction coefficient of less than 0.023 (or less than 0.021) when measured at a kinematic viscosity of 15 mm ² / s and a sliding / rolling ratio of 40%. In another embodiment, the isomerized base oil has a traction coefficient of less than 0.017 when measured at a kinematic viscosity of 15 mm ² / s and a sliding / rolling ratio of 40%. In a further embodiment, the isomerized base oil has a viscosity index greater than 150 and a traction coefficient of less than 0.015 when measured at a kinematic viscosity of 15 mm ² / s and a sliding / rolling ratio of 40%.

In some embodiments, the low traction coefficient isomerized base oil also exhibits higher kinematic viscosity and higher boiling points. In one embodiment, the base oil has a traction coefficient less than 0.015 and a 50 wt% boiling point greater than 565 ° C (1050 ° F). In a further embodiment, the base oil has a traction coefficient less than 0.011 and a 50 wt% boiling point according to ASTM D 6352-04 greater than 582 ° C (1080 ° F).

In some embodiments, the low traction coefficient isomerized base oil also exhibits unique branching properties according to NMR, such as a branching index less than or equal to 23.4, a branching neighborhood greater than or equal to 22.0 and a number of free carbon atoms between 9 and 30. In one embodiment the base oil at least 4 wt .-% of naphthenic carbon, in another embodiment at least 5 wt .-% naphthenic carbon according to ndM analysis after ASTM D 3238-95 (Re-approved in 2005).

In one embodiment, the isomerized base oil is prepared in a process wherein the oil isomerate intermediate comprises paraffinic hydrocarbon components and wherein the extent of branching is less than 7 alkyl branches per 100 carbon atoms and wherein the base oil comprises paraffinic hydrocarbon components having the extent Branch is less than 8 alkyl branches per 100 carbon atoms and less than 20 wt .-% of the alkyl branches are present at the 2-position. In one embodiment, the FT base oil has a pour point of less than -8 ° C; a kinematic viscosity at 100 ° C of at least 3.2 mm ² / s and a viscosity index greater than the viscosity index calculated by the equation: = 22 × Ln (kinematic viscosity at 100 ° C) + 132.

In In one embodiment, the base oil comprises more as 10% by weight and less than 70% by weight of all molecules with cycloparaffin functionality and a ratio the weight percent of molecules with monocycloparaffin functionality to the weight percent of molecules with multicycloparaffin functionality greater than 15.

In one embodiment, the isomerized base oil has an average molecular weight between 600 and 1100 and an average degree of branching in the molecules between 6.5 and 10 alkyl branches per 100 carbon atoms. In another embodiment, the isomerized base oil has a kinematic viscosity between about 8 and about 25 mm ² / s and an average degree of branching in the molecules between 6.5 and 10 alkyl branches per 100 carbon atoms.

In one embodiment, the isomerized base oil is obtained in a process in which the high paraffin wax is hydroisomerized at a hydrogen to feed ratio of 712.4 to 3562 liters H ₂ / liter of oil such that the base oil is greater than 10% total by weight of molecules having cycloparaffin functionality and a ratio of the weight percent of molecules having monocycloparaffin functionality to the weight percent of molecules having multicycloparaffin functionality greater than 15. In another embodiment, the base oil has a viscosity index greater than the amount defined by the equation: 28 × Ln (kinematic viscosity at 100 ° C) + 95. In a third embodiment, the base oil comprises less than 0.30 % By weight aromatics; more than 10% by weight molecules with cycloparaf fin functionality; a ratio of the weight percent of molecules having monocycloparaffin functionality to the weight percent of molecules having multicycloparaffin functionality greater than 20 and a viscosity index greater than 28 × Ln (kinematic viscosity at 100 ° C) + 110. In a fourth embodiment, the base oil also has a kinematic viscosity at 100 ° C greater than 6 mm ² / s. In a fifth embodiment, the base oil has less than 0.05 weight percent aromatics and a viscosity index greater than 28 × Ln (kinematic viscosity at 100 ° C) + 95. In a sixth embodiment, the base oil has less than 0.30 weight percent aromatics, more weight percent molecules with a cycloparaffin functionality than the kinematic viscosity at 100 ° C, in mm ² / s, multiplied by 3, and a ratio of molecules with monocycloparaffin functionality to the molecules having multicycloparaffin functionality greater than 15.

In one embodiment, the isomerized base oil contains between 2 and 10% naphthenic carbon, measured according to ndM. In one embodiment, the base oil has a kinematic viscosity at 100 ° C of 1.5-3.0 mm ² / s and 2-3% naphthenic carbon; in another embodiment, a kinematic viscosity at 100 ° C of 1.8-3.5 mm ² / s and 2.5-4% naphthenic carbon; in a third embodiment, a kinematic viscosity at 100 ° C of 3-6 mm ² / s and 2.7-5% naphthenic carbon; in a fourth embodiment, a kinematic viscosity at 100 ° C of 10-30 mm ² / s and more than 5.2% naphthenic carbon.

In One embodiment has the isomerized base oil an average molecular weight greater than 475; one Viscosity index greater than 140 and less as 10 wt .-% olefins. The base oil improves the air separation and the low foaming properties of the mixture when is added to the hydraulic fluid.

In one embodiment, the isomerized base oil is a white oil, as used in US Pat U.S. Patent 7,214,307 and in the US patent publication US20060016724 is disclosed. In one embodiment, the isomerized base oil has a kinematic viscosity at 100 ° C between about 1.5 cSt and 36 mm ² / s; a viscosity index greater than the number calculated by the equation: viscosity index = 28 × Ln (kinematic viscosity at 100 ° C) + 95, between 5 and less than 18 weight percent molecules with cycloparaffin functionality, less than 1 , 2 wt% molecules with multicycloparaffin functionality, a pour point below 0 ° C and a Saybolt color of +20 or greater. In one embodiment, the hydraulic composition employs a base oil consisting of at least one of the isomerized base oils described above. In another embodiment, the composition consists essentially of at least one Fischer-Tropsch base oil.

In one embodiment, the hydraulic fluid comprises an isomerized base oil having between 0.001 and 0.05 weight percent aromatics and a molecular weight greater than 600 ASTM D 2503-92 (Re-approved in 2002) and 0 to 0.10 weight percent olefins. In another embodiment, the isomerized base oil has a molecular weight above 650. In a third embodiment, the total isomerized base oil contains more than 25 weight percent cycloparaffin functionality molecules and the ratio of the monocycloparaffin functionality molecules to the multicycloparaffin functionality molecules is greater than 10.

In one embodiment, the hydraulic fluid comprises an isomerized base oil having a kinematic viscosity at 100 ° C between 6 mm ² / s and 20 mm ² / s; a kinematic viscosity at 40 ° C between 30 mm ² / s and 120 mm ² / s; a viscosity index between 150 and 165; a cold start viscosity in the range of 3000-50000 mPa · s at -30 ° C, 2000-20000 mPa · s at -25 ° C; a pour point in the range of -2 and -30 ° C; a molecular weight of 500-800; a density in the range of 0.820 to 0.840; a range of 92-95% for the paraffinic carbon; a range of 5-8% for the naphthenic carbon; Oxidizer BN of 30 to 60 hours and a Noack volatility in wt .-% of 0.50 to 5.

In one embodiment, the hydraulic fluid composition employs at least one isomerized base oil (or mixtures of isomerized base oils) and optionally 5 to 50 weight percent (based on the weight of the base oil matrix) of at least one other type of oil, e.g. B. base lubricating oils selected from vegetable oils (eg, soy, sunflower, rapeseed, etc.), Group I, II, III, IV, and V base lubricating oils as defined in the API Interchange Guidelines, and mixtures thereof. Examples include conventionally used mineral oils, synthetic hydrocarbon oils, or synthetic ester oils, or mixtures thereof, as appropriate to the application. Mineral base lubricating oils may be any of the conventionally refined base substances resulting from paraffinic, naphthenic and mixed base stocks. Synthetic lubricating oils that can be used include esters of glycols and complex esters. Other synthetic oils which may be used include synthetic hydrocarbons such as polyalphaolefins; Alkylbenzenes, e.g. B. alkylate bottoms from the alkylation of benzene with tetrapropylene or the copolymers of ethylene len and propylene; Silicone oils, e.g. Ethylphenylpolysiloxanes, methylpolysiloxanes, etc., polyglycol oils, e.g. For example, those obtained by condensing butyl alcohol with propylene oxide; etc. Other suitable synthetic oils include polyphenyl ethers, eg. For example, those having 3 to 7 ether bonds and 4 to 8 phenyl groups. Other suitable synthetic oils include polyisobutenes and alkylated aromatics such as alkylated naphthalenes.

Further Components: The hydraulic fluid composition is characterized that they provide excellent oxidation resistance a minimal amount of added oxidation additives having. However, if necessary, antioxidants (oxidation additives) in a smaller amount of 0.01 to 1 wt .-% are added. Examples for antioxidants are u. a., but are not limited to the group with phenolic antioxidants, aromatic amine antioxidants, sulfurized phenolic antioxidants and organic phosphites. Examples of phenolic antioxidants include 2,6-di-tert-butylphenol, liquid mixtures of tertiary butylated phenols, 2,6-di-tert-butyl-4-methylphenol, 4,4-methylenebis (2,6-di-tert-butylphenol), 2,2'-methylenebis (4-methyl-6-tert-butylphenol), mixed polyalkylphenols with methylene bridge, 4,4'-thiobis- (2-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), 4,4'-isopropylidenebis (2,6-di-tert-butylphenol), 2,2'-methylenebis (4-methyl-6-nonylphenol), 2,2'-isobutylidenebis (4,6-dimethylphenol), 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-1-dimethylamino-p-cresol, 2,6-di-tert-4- (N, N'-dimethylaminomethylphenol), 4,4'-thiobis (2-methyl-6-tert-butylphenol), 2,2'-thiobis (4-methyl-6-tert-butylphenol), bis (butylbenzyl-3-methyl-4-hydroxy-5-tert-10-butylbenzyl) sulfide, Bis (3,5-di-tert-butyl-4-hydroxybenzyl), 2,2'-5-methylenebis (4-methyl-6-cyclohexylphenol), N, N'-di-sec-butylphenylenediamine, 4-isopropylaminodiphenylamine, Phenyl-alpha-naphthylamine, phenyl-alpha-naphthylamine and ring-alkylated Diphenylamines. Examples are u. a. the sterically hindered tertiary butylated phenols, bisphenols and cinnamic acid derivatives and their combinations. In yet another embodiment the antioxidant is an organic phosphonate with at least one direct carbon-phosphorus bond. Oxidation inhibitors of Diphenylamine type are u. a., but are not limited on alkylated diphenylamine, phenyl-alpha-naphthylamine and alkylated alpha-naphthylamine. Other oxidation inhibitor types are u. a. Metal dithiocarbamate (e.g., zinc dithiocarbamate) and 15-methylenebis (dibutyldithiocarbamate).

In In one embodiment, the composition optionally comprises 0.01 to 1% by weight of a sealer swelling agent. In another Embodiment is the amount of seal swelling additives less than 0.5% by weight. Examples of known optional Seal swelling agents are u. a., but are not limited to Dioctyl phthalate, tert. Diamid, dioctyl sebacate, polyol ester, branched chain Carboxylic acid esters and mixtures thereof.

In One embodiment includes the hydraulic fluid composition further 0.001 to 6 wt .-%. of at least one viscosity index modifier. In one embodiment, the viscosity index modifiers used are a mixture of modifiers selected from Polyacrylate or polymethacrylate and polymers, the vinyl aromatic units and esterified carboxylic containing units. In one embodiment For example, the first viscosity index modifier is a polyacrylate or a polymethacrylate having an average molecular weight from 10,000 to 60,000. In another embodiment, the second viscosity index modifier vinyl aromatic units and esterified carboxylated units and has an average Molecular weight of 100,000 to 200,000. In another embodiment the viscosity index modifier is a mixture of one Polymethacrylate viscosity index improver with a weight average Molecular weight of 25,000 to 150,000 and a shear stability index less than 5 and a polymethacrylate viscosity index improver having a weight average molecular weight of from 500,000 to 1,000,000 and a shear stability index of 25 to 60. In yet another embodiment, the viscosity modifier becomes from the group of polymers of the polymethacrylate type, ethylene-propylene copolymers, Styrene-isoprene copolymers, hydrated styrene-isoprene copolymers, Polyisobutylene and mixtures thereof selected.

In one embodiment, the hydraulic fluid further comprises at least one surfactant, also referred to as a dispersant, which may generally be classified into anionic, cationic, zwitterionic or nonionic. In some embodiments, a dispersant may be used alone or in a combination of one or more species or types of dispersants. Examples include an oil-soluble dispersant selected from the group consisting of succinimide dispersants, succinic ester dispersants, succinic ester amide dispersants, Mannich base dispersants, their phosphorylated forms, and their boronated forms. The dispersants can be masked with acidic molecules that can react with secondary amino groups. The molecular weight of the hydrocarbon groups may range from 600 to 3000, e.g. From 750 to 2500 and as Another example of 900 to 1500 are. In one embodiment, the dispersant is selected from the group consisting of alkenyl succinimides, alkenyl succinimides modified with other organic compounds, alkenyl succinimides modified by post-treatment with ethylene carbonate or boric acid, pentaerythritols, phenate salicylates and their post-treated derivatives, alkali metal or mixed alkali metal , Alkaline earth metal borates, dispersions of hydrated alkali metal borates, dispersions of alkaline earth metal borates, ashless polyamide dispersants and the like, or mixtures of such dispersants.

In In some embodiments, the ashless dispersant the products of the reaction of a polyethylene polyamine, e.g. B. from Triethylenetetramine or tetraethylenepentamine, with a hydrocarbyl-substituted Carboxylic acid or an anhydride prepared by Reaction of a polyolefin, such as polyisobutene, with a suitable Molecular weight with an unsaturated polycarboxylic acid or an anhydride, e.g. B. maleic anhydride, maleic acid, Fumaric acid or the like, including mixtures of two or more such substances. In another embodiment For example, the ashless dispersant is a borated dispersant. Borated dispersants can be prepared by: boronated (borated) an ashless dispersant, the basic Nitrogen and / or at least one hydroxyl group in the molecule such as succinimide dispersant, succinamide dispersant, Succinate ester dispersant, succinic ester amide dispersant, Mannich-base dispersants or hydrocarbylamine or polyamine dispersants.

In In one embodiment, the hydraulic fluid further comprises one or more metal detergents. Examples of metal detergents include an oil soluble neutral or overbased Salt of alkali or alkaline earth metal with one or more of the following acid substances (or mixtures thereof): (1) a sulphonic acid, (2) a carboxylic acid, (3) a salicylic acid, (4) an alkylphenol, (5) a sulfurized alkylphenol and (6) an organic phosphoric acid represented by at least a direct carbon-phosphorus bond is characterized as Phosphonate. Such organic phosphoric acid may include those which are prepared by treatment of an olefin polymer (eg, polyisobutylene having a molecular weight of 1000) with a Phosphating agents, such as phosphorus trichloride, phosphorus heptasulfide, phosphorus pentasulfide, Phosphorus trichloride, and sulfur, white phosphorus and a Sulfur halide or phosphorothionic acid chloride. In still In another embodiment, the metal detergent becomes from the group with sulfurized or unsulfurized alkyl or Alkenyl phenates, alkyl or alkenyl aromatic sulfonates, borated Sulfonates, sulfurized or unsulfurized metal salts of Multihydroxyalkyl or alkenyl aromatic compounds, alkyl or Alkenyl hydroxyaromatic sulfonates, sulfurized or unsulfurized Alkyl or alkenyl naphthenates, metal salts of alkanoic acids, Metal salts of an alkyl or alkenylmultic acid and their selected from chemical and physical mixtures.

In one embodiment, the hydraulic fluid further comprises at least one corrosion inhibitor selected from thiazoles, triazoles and thiadiazoles. Examples of such compounds include benzotriazole, tolyltriazole, octyltriazole, decyltriazole, dodecyltriazole, mercapto-2-benzothiazole, 2,5-dimercapto-1,3,4-thiadiazole, 2-mercapto-5-hydrocarbylthio-1,3,4- thiadiazoles, 2-mercapto-5-hydrocarbyldithio-1,3,4-thiadiazoles, bis-2,5- (hydrocarbylthio) -1,3,4-thiadiazoles and bis-2,5- (hydrocarbyldithio) -1,3, 4-thiadiazoles. Suitable compounds include the 1,3,4-thiadiazoles, a number of which are available as a commodity, and also combinations of triazoles such as tolyltriazole with a 1,3,5-thiadiazole such as 2,5-bis (alkyldithio) - 1,3,4-thiadiazole. The 1,3,4-thiadiazoles are generally synthesized from hydrazine and carbon disulfide by known methods. See for example the U.S. Patents 2,765,289 ; 2,749,311 ; 2,760,933 ; 2,850,453 ; 2,910,439 ; 3,663,561 ; 3,862,798 and 3,840,549 ,

In one embodiment, the hydraulic fluid composition further comprises rust or corrosion inhibitors selected from the group of monocarboxylic acids and polycarboxylic acids. Examples of suitable monocarboxylic acids are octanoic acid, decanoic acid and dodecanoic acid. Suitable polycarboxylic acids include dimer and trimer acids made from acids such as tall oil fatty acids, oleic acid, linoleic acid or the like. Another suitable type of rust inhibitor may include alkenyl succinic and alkenyl succinic anhydride corrosion inhibitors, e.g. Tetrapropenylsuccinic acid, tetrapropenylsuccinic anhydride, tetradecenylsuccinic acid, tetradecenylsuccinic anhydride, hexadecenylsuccinic acid, hexadecenylsuccinic anhydride and the like. Also suitable are the half-esters of alkenyl succinic acids having 8 to 24 carbon atoms in the alkenyl group, with alcohols such as polyglycols. Other suitable rust or corrosion inhibitors include etheramines; acid phosphates; amines; polyethoxylated compounds such as ethoxylated amines, ethoxylated phenols and ethoxylated alcohols; imidazolines; Amino-succinic acids or their derivatives and the like. Mixtures of such rust or corrosion inhibitors may be used. Other examples of rust inhibitors include polyethoxylated Phe nol, neutral calcium sulfonate and basic calcium sulfonate.

In In one embodiment, the hydraulic fluid also comprises at least one friction modifier selected from Group with succinimide, a bis-succinimide, an alkylated fatty amine, an ethoxylated fatty amine, an amide, a glycerol ester, a Imidazoline, fatty alcohol, fatty acid, amine, borated ester, other esters, phosphates, phosphites, phosphonates and mixtures thereof.

In One embodiment includes the hydraulic fluid composition at least one anti-wear additive. Examples for such funds u. a., but are not limited on phosphates, carbamates, esters and molybdenum complexes. In one embodiment, the antiwear additive becomes from the group with a zinc dialkyldithiophosphate (ZDDP), a Alkyl phosphite, a trialkyl phosphite and amine salts of dialkyl and monoalkyl phosphoric acid.

In In one embodiment, the hydraulic fluid optionally comprises a sufficient amount of a pour point depressor that the pour point of the hydraulic fluid at least 3 ° C below of the pour point of a mixture in which no pour point depressant is present. Pour point depressants are known in the art and are u. a., but are not limited to esters of Maleic anhydride-styrene copolymers, polymethacrylates, Polyacrylates, polyacrylamides, condensation products of halogen paraffin waxes and aromatic compounds, vinyl carboxylate polymers and terpolymers from dialkyl fumarates, vinyl esters of fatty acids, ethylene-vinyl acetate copolymers, Alkylphenol-formaldehyde condensation resins, alkyl vinyl ethers, olefin copolymers and their mixtures.

In In one embodiment, the pour point depressant is one Pour point reducing mixing component. In one embodiment The pour point reducing mixture component is an isomerized one a bottoms product of the vacuum distillation originating from a Fischer-Tropsch process, which is a high-boiling Syncrude fraction, which was isomerized under controlled conditions, leaving a specific degree of alkyl branching in the molecule has been. Syncrude made in a Fischer-Tropsch process comprises a mixture of different solid, liquid and gaseous hydrocarbons. If the Fischer-Tropsch waxes through various processes, such as hydroprocessing and distillation, be converted into Fischer-Tropsch base oils the base oils produced in different, narrow separated viscosity ranges. The swamp products that after recovering the base lubricating oil fractions from the Vacuum column remain, are generally for the use as a base lubricating oil itself unsuitable and are usually used for conversion to low molecular weight Products returned to a hydrocracking plant.

In In one embodiment, the pour point reducing blend component is an isomerized Fischer-Tropsch process Bottom product of vacuum distillation with an average Molecular weight between 600 and 1100 and an average Degree of branching in the molecules between 6.5 and 10 Alkyl branches per 100 carbon atoms. In general are the higher molecular weight hydrocarbons more effective than pour point reducing Mixture components as the low molecular weight hydrocarbons. In one embodiment, a higher separation point in a vacuum distillation unit, which leads to a higher boiling sump material leads to the production of pour point-reducing Blending component used. The higher separation point has Moreover, it has the advantage that it leads to a higher yield of Distillate-base oil fractions leads. In one embodiment is the pour point reducing mixture component an isomerized, from a Fischer-Tropsch process derived bottom product of Vacuum distillation with a pour point of at least 3 ° C is higher than the pour point of the distillate base oil, with which it is mixed.

In In one embodiment, the 10 percent point is in the boiling range the pour point reducing blend component at which it is is a bottoms product of a vacuum distillation, between about 850 ° F and 1050 ° F (454-565 ° C). In another embodiment, the pour point reducing blend component is derived either from Fischer-Tropsch or from petroleum products and has a boiling range above 950 ° F (510 ° C) and contains at least 50% by weight of paraffins. In one more Another embodiment has the pour point decreasing Mixture component has a boiling range above 1050 ° F (565 ° C).

In another embodiment, the pour point reducing blend component is an isomerized petroleum-derived base oil containing material having a boiling range above about 1050 ° F. In one embodiment, the isomerized bottoms are solvent dewaxed prior to use as a pour point depressant blend component. It turned out that the waxy Pro This product, which is further separated from the pour point depressant mixture component during solvent dewaxing, has excellent pour point depressant properties compared with the oily product obtained after solvent dewaxing.

In one embodiment, the pour point reducing blend component has an average degree of branching in the molecules in the range of 6.5 to 10 alkyl branches per 100 carbon atoms. In another embodiment, the pour point reducing blend component has an average molecular weight between 600 and 1100; in a third embodiment, between 700 and 1000. In one embodiment, the pour point reducing blend component has a kinematic viscosity at 100 ° C of 8-30 mm ² / s, with the 10% point boiling range of the bottoms being between about 850 and 1050 ° F is. In yet another embodiment, the pour point reducing blend component has a kinematic viscosity at 100 ° C of 15-20 mm ² / s and a pour point of -8 to -12 ° C.

In another embodiment, the pour point reducing blend component is-an isomerized oil having a kinematic viscosity at 100 ° C of at least about 8 mm ² / s, which is made of polyethylene plastic. In another embodiment, the pour point reducing blend component is made from plastic waste. In yet another embodiment, the pour point reducing blend component is prepared in a process comprising: pyrolysis of polyethylene plastic, heavy fraction separation, hydrotreating the heavy fraction, catalytic isomerization of the hydrotreated heavy fraction, and capturing the pour point reducing blend component a kinematic viscosity at 100 ° C of at least about 8 mm ² / s. In one embodiment, the pour point depressant blend component derived from polyethylene plastic has a boiling range above 1050 ° F (565 ° C) or even a boiling range above 1200 ° F (649 ° C).

In In one embodiment, the hydraulic fluid further comprises at least one extreme pressure anti-wear agent (EP / AW agent). Examples are u. a. Zinc dialky-1-dithiophosphate (of primary Alkyl, secondary alkyl and aryl type), diphenyl sulfide, Methyl trichloro stearate, chlorinated naphthalene, fluoroalkyl polysiloxane, lead naphthenate, neutralized phosphates, dithiophosphates and sulfur-free phosphates.

The Hydraulic fluid may be in addition to those described above also include conventional additives. Examples are u. a., but are not limited to, dyes, metal deactivators, such as disalicylidenepropylenediamine, triazole derivatives, thiadiazole derivatives and mercaptobenzimidazoles, antifoam and antifoam additives, such as alkyl methacrylate polymers and dimethyl silicone polymers, and / or Air separation additives. Such additives can be added be, so z. B. multivariate viscometric functionality is obtained.

In one embodiment, the additional ingredients are added as ready-formulated additive packages formulated to meet the initial requirements of the equipment manufacturer for a hydraulic fluid such that e.g. B. the fluid is able to perform bank and dynamometer tests. The package to be used depends in part on the requirements of the specific equipment that is to receive the lubricant composition. Examples of additives and additive packages that have been used in hydraulic fluids are described in U.S.P. U.S. Patents 5,635,459 and 5,843,873 disclosed. In one embodiment, the additive package includes, among other substances, metal-containing detergents, a calcium overbased sulfonate detergent in an amount of 1-2% (eg, 1.41%); Antioxidants or antiwear agents, a zinc dialkyldithiophosphate in an amount of 1-2% (eg, 1.69%); 0.5 to 2% (eg, 1.03%) of friction modifiers and 0.1 to 2% (eg, 0.25%) of a nitrogen-containing dispersant, such as succinimide dispersant. Other conventional components may also be present, if desired.

Some of the aforementioned additives can provide multiple effects; for example, a single additive can serve as a dispersant and as an oxidation inhibitor. In one embodiment, when the hydraulic fluid contains one or more of the above additives, each additive is typically blended into the base oil in an amount sufficient to provide the additive with its desired function. Although not critical, it may be desirable to prepare one or more additive concentrates that include additives (where concentrates containing at least one of the above additives are sometimes referred to as "additive packages") and those to the hydraulic fluid composition should be added. The final composition may contain from about 0.001% to 20% by weight of the concentrate, with the remainder being the oil of lubricating viscosity. The components can be mixed in any order and can be mixed in as combinations of components become.

Production method: The additives used to formulate the hydraulic fluid composition can be used in the base oil matrix be mixed individually or in different subcombinations, so that the hydraulic fluid is obtained. In one embodiment all components are simultaneously using an additive concentrate (i.e., additives and a diluent, such as a hydrocarbon solvent) mixed. The use of an additive concentrate benefits from mutual compatibility, by the combination the ingredients is achieved when in the form of an additive concentrate is present.

In In another embodiment, the hydraulic fluid prepared by mixing the base oil matrix with the separate ones Additive or additive package (s) at a suitable temperature, as about 60 ° C until homogenous.

Properties: In one embodiment, the hydraulic fluid is characterized by excellent oxidation resistance, d. H. it meets all performance requirements of JCMAS HK. In the JCMA test, which simulates a partial deterioration of a hydraulic fluid, how to observe them in practical use, eg. B. the isolated Compression state, the oxidation resistance of a Evaluated hydraulic fluids on the following basis: a) change in the fluid viscosity; b) increasing the acid number; c) amount of sludge produced; and d) change in copper content in a fluid.

In In one embodiment, the hydraulic fluid is characterized that it has excellent oxidation resistance with a change in the kinematic viscosity of less than 5% (from initial viscosity) a period of 1000 hours when operating in a JCMAS HK test having. in a second embodiment the viscosity variation is less than 2.5% a period of 1000 hours.

In One embodiment is the hydraulic fluid composition characterized in that they have a viscosity index (VI) of at least 140 very resistant to the Use at a wide range of temperatures. In a In another embodiment, the hydraulic fluid has a VI of at least 150, in a third embodiment a VI of at least 160.

In One embodiment is the hydraulic fluid composition characterized in that they have a flash point of at least 270 ° C especially suitable for use with Applications that require the use of refractory fluids, z. B. an electro-hydraulic control for driving electrical Generators in a power plant. In a second embodiment the hydraulic fluid has a flashpoint of at least 280 ° C. In one embodiment, the hydraulic fluid composition an autoignition temperature of at least 360 ° C.

In one embodiment, the hydraulic fluid is characterized in that it by means of ASTM D 3427-06 measured air separation less than 0.8 minutes at 50 ° C and a sequence II foaming tendency according to ASTM D 892-03 of less than 50 ml has excellent air-separation properties and a low foaming tendency.

In one embodiment, the hydraulic fluid composition consisting essentially of at least one isomerized base oil, such as a base oil derived from a Fischer-Tropsch process, exhibits OECD 301D levels ranging from> 30% inherently biodegradable to light biodegradable with> 90%. JCMAS HKB is the specification for biodegradable hydraulic fluids for construction machinery with a current biodegradability standard of at least 60% or greater within 28 days as measured by testing procedures such as OECD 301D. In one embodiment, a hydraulic fluid composition containing an isomerized base oil having a kinematic viscosity at 40 ° C of <100 mm ² / s exhibits a biodegradability of about 30% according to OECD 301D. In a second embodiment, a hydraulic fluid composition containing an isomerized base oil having a kinematic viscosity at 40 ° C of <40 mm ² / s exhibits a biodegradability of approximately 40% according to OECD 301D. In a third embodiment, a hydraulic fluid composition having a base oil matrix with a kinematic viscosity at 40 ° C of <8 mm ² / s exhibits a biodegradability according to OECD 301D of> = 40%. In a fourth embodiment, a hydraulic fluid composition having a base oil matrix with a kinematic viscosity at 40 ° C of <11 mm ² / s exhibits a biodegradability of about 80% according to OECD 301D. In a fifth embodiment, a hydraulic fluid composition having a base oil matrix with a kinematic viscosity at 40 ° C. of <6 mm ² / s exhibits a bio logical degradability according to OECD 301D of> 93%.

In one embodiment, the hydraulic fluid composition has an RPVOT of greater than 600 minutes, as described in U.S. Pat ASTM D2272-02 is measured. In another embodiment, the RPVOT is greater than 1000 minutes. In a third embodiment, the hydraulic fluid composition has a cold start viscosity of 4000 to 50,000 cP at -30 ° C and 1000 to 25000 cP at -25 ° C. In yet another embodiment, the hydraulic fluid composition has a kinematic viscosity at 40 ° C of 10 to 800 mm ² / s.

applications: In one embodiment, the composition is in hydraulic pumps used. The performance of pumps and motors is a crucial one Factor in the reliability of the entire hydraulic System. An important task of a hydraulic pump is the translation of energy from electrical or mechanical energy into hydraulic Energy, z. B. volumetric flow and pressure.

In In another embodiment, the hydraulic fluid composition the fluid reservoir of the equipment that lubricated, fed and thus the movable Sharing the equipment itself, including mobile and not mobile equipment, but not limited to including turbines, tractors, vehicles and mobile Off-road equipment, but not limited to this. Moving parts are u. a. a power transmission, a hydrostatic power transmission, a transmission, a drive, a hydraulic system, etc.

The The following examples are not intended to be limiting, but rather to illustrate aspects of the present invention.

EXAMPLES. The examples were prepared by placing the components in the in Table 1 were mixed. The formulas were the piston pump test according to the standard specifications of JCMAS HK submitted by the Technical Committee for Fuels and lubricants of Japan Construction Mechanization Association (JCMA) were developed.

FTBO Base Oils are from Chevron Corporation, San Ramon, CA. The properties the FTBO base oils used in the examples are in Table 4.

Nexbase ^TM 3060 is a colorless, catalytically hydroisomerized and dewaxed Group III base oil from Neste Oil Corporation.

Pennzoil ^™ HC 575 is a Group II mineral oil from Pennzoil-Quaker State Company.

additive 1 is a commercially available rust and oxidation package.

additive 2 is an ashless anti-wear and extreme pressure triaryl phosphate additive.

additive 3 is an amine phosphate, an ashless multifunctional additive with Extreme pressure / anti-wear and anti-rust activity, which usually contains 4.9% phosphorus and 2.7% nitrogen.

additive 4 is a tolutriazole derivative as a metal deactivator.

additive 5 is a commercial sorbitan monooleate.

additive 6 is a polyalkyl methacrylate (C11-C20).

additive 7 is a low molecular weight organic acrylic polymer.

The Results of the experiments show that given the same amount on rust, anti-wear and oxidation additives (in Examples B1-B9) of formula A superior is that of the group II / III base oil of the prior art contains (and used in Examples A1-B9 has been). For mel B resulted in a smaller amount of educated Deposits for better results in the Rotary Pressure Vessel Oxidation test (RPVOT of 1112 vs. 578), a better one Total acid number (TAN of 0.17 mg KOH / g versus 0.45 mg KOH / g), better air separation (air separation of 0 compared to 6 min at 50 ° C) and lower foaming tendency (Foaming sequence of 0 ml at 0/10 min).

Tabelle 3 FTBO M FTBO H kinemat. Viskosität @ 40°C, mm²/s. 42.3 106.4 kinemat. Viskosität @ 100°C, mm²/s. 7.929 16.01 Viskositatsindex 162 161 Kaltstartviskosität @ –40°C, cP 24,287 - Kartstartviskosität @ –35°C, cP 10,149 - Kaltstartviskosität @ –30°C, cP 4,936 46,991 Kaltstartviskosität @ –28°C, cP 2,584 18,905 Pourpunkt, °C –11 –10 n-d-m Molekulargewicht, gm/mol (VPO) 549 743 Dichte, gm/ml 0.8241 0.8330 Brechungsindex 1.4595 1.4641 paraffinischer Kohlenstoff, % 93.68 92.98 naphthenischer Kohlenstoff, % 6.32 7.02 aromatischer Kohlenstoff, % 0.00 0.00 Oxidator BN, Std. 45.86 45.32 Noack, Gew.-% 2.02 0.95 HPLC-UV (LUBES) 1-Ring 0.00414 0.02737 2-Ring 0.00124 0.00325 Gesamt-Aromaten 0.00538 0.03082 SIMDIST TBP (WT%), F TBP @0.5 832 915 TBP @5 869 963 TBP @10 884 988 TBP @20 902 1011 TBP @30 916 1040 TBP @40 928 1057 TBP @50 940 1074 TBP @60 953 1092 TBP @70 971 1113 TBP @80 989 1141 TBP @90 1006 1181 TBP @95 1022 1213 TBP @99.5 1056 1290 FIMS durch Sonden-Proben-Einbringung tof 564 tof 556 Gesättigte 70 65.4 1-Ungesättigtheit 27.9 33.1 2-Ungesättigtheit 2 1.2 3-Ungesättigtheit 0 0.3 4-Ungesättigtheit 0 0 5-Ungesättigtheit 0 0 6-Ungesättigtheit 0.1 0 % Olefine gemäß Protonen-NMR 0.00 0.00 Monocycloparaffin (FIMS1-ungesättigt.-NMR-Olefine) 27.9 33.1 Multicycloparaffin (FIMS2-ungesätt.-6ungesätt-HPLC-UV-Aromaten) 2.1 1.5 Verhältnis Mono/Multi 13.3 22.5 1 compares the change in the kinematic viscosity at 40 ° C of the fluid over time (test periods of 0-1000 hours) between Formula A containing the Group II / III base oils of the prior art, and Formula B, which is an embodiment of the Hydraulic fluid of the invention. 2 Compares the change in total acid number over time between Formula A and Formula B. Formula B shows excellent stability for small changes / variations in fluid viscosity at 40 ° C and in total acid value as a function of time compared to the more drastic variations in the formulation of the prior art. Table 1

Table 3 FTBO M FTBO H Kinematic. Viscosity @ 40 ° C, mm ² / s. 42.3 106.4 Kinematic. Viscosity @ 100 ° C, mm ² / s. 7929 1.16 viscosity index 162 161 Cold start viscosity @ -40 ° C, cP 24.287 - Kartstart Viscosity @ -35 ° C, cP 10.149 - Cold start viscosity @ -30 ° C, cP 4,936 46,991 Cold start viscosity @ -28 ° C, cP 2,584 18.905 Pour point, ° C -11 -10 ndm Molecular weight, gm / mol (VPO) 549 743 Density, gm / ml 0.8241 0.8330 refractive index 1.4595 1.4641 paraffinic carbon,% 93.68 92.98 naphthenic carbon,% 6:32 7:02 aromatic carbon,% 00:00 00:00 Oxidizer BN, Std. 45.86 45.32 Noack,% by weight 2:02 0.95 HPLC-UV (LUBES) 1-Ring 0.00414 0.02737 2-ring 0.00124 0.00325 Total aromatics 0.00538 0.03082 SIMDIST TBP (WT%), F TBP @ 0.5 832 915 TBP @ 5 869 963 TBP @ 10 884 988 TBP @ 20 902 1011 TBP @ 30 916 1040 TBP @ 40 928 1057 TBP @ 50 940 1074 TBP @ 60 953 1092 TBP @ 70 971 1113 TBP @ 80 989 1141 TBP @ 90 1006 1181 TBP @ 95 1022 1213 TBP @ 99.5 1056 1290 FIMS by probe-sample introduction tof 564 tof 556 saturated 70 65.4 1 unsaturation 27.9 33.1 2 unsaturation 2 1.2 3 unsaturation 0 0.3 4 unsaturation 0 0 5 unsaturation 0 0 6 unsaturation 0.1 0 % Olefins according to proton NMR 00:00 00:00 Monocycloparaffin (FIMS1 unsaturated NMR olefins) 27.9 33.1 Multicycloparaffin (FIMS2 unsaturated 6-unsaturated HPLC-UV-aromatics) 2.1 1.5 Ratio mono / multi 13.3 22.5

For the purposes of this specification and the appended claims, unless otherwise indicated, all numbers expressing amounts, percentages or proportions and other numerical values used in the specification and claims are to be understood to be embraced in all respects Cases are modified by the term "about". Thus, unless otherwise indicated, the numerical parameters referred to in the following description and appended claims are approximate, which may vary depending on the desired characteristics desired to be obtained and / or the accuracy of an instrument for measuring the value. In addition, all areas disclosed here including the endpoints are to be understood and can be combined independently. In general, unless otherwise stated, individual elements may be plural and vice versa without loss of generality. As used herein, the term "include, include, and others" and its grammatical variations are not intended to be limiting, so listing items in a list is not to the exclusion of others more similar Points that can be used for or added to the listed points.

Summary

It becomes a hydraulic fluid composition excellent in oxidation resistance provided, which are made from an isomerized base oil becomes. The composition comprises (i) 80 to 99.999% by weight of one Base lubricating oil with consecutive numbers of carbon atoms, less than 10% by weight of naphthenic carbon according to n-d-M; and (ii) 0.001-20 wt.% of at least one additive package. The hydraulic fluid composition meets the performance specifications at least one of the standard defaults JCMAS HK and JCMAS HKB, that of the Technical Committee for Fuels and Lubricants of the Japan Construction Mechanization Association (JCMA) were issued.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

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Claims (15)

Hydraulic fluid composition comprising (i) From 80 to 99.999% by weight of a base lubricating oil and (ii) 0.001-20 wt .-% of at least one additive package, wherein the Basic lubricating oil consecutive numbers of carbon atoms has less than 10% by weight of naphthenic carbon according to n-d-M, less than 0.10% by weight of olefins and less than 0.05% by weight of aromatics, more than 25% by weight of all molecules having cycloparaffin functionality and a ratio of molecules with monocycloparaffin functionality to molecules with multicycloparaffin functionality greater than 10; and wherein the hydraulic fluid composition at least one of the JCMAS HK and JCMAS HKB 2005 standards Fulfills. A hydraulic fluid composition according to claim 1 a viscosity index (VI) of at least 140 and one Flash point of at least 270 ° C. A hydraulic fluid composition according to any one of the claims 1-2 with air separation according to ASTM D 3427-06 less than 0.8 minutes at 50 ° C and a sequence II foaming tendency according to ASTM D 892-03 of less than 50 ml. A hydraulic fluid composition according to any one of the claims 1-3 with a VI of at least 160. A hydraulic fluid composition according to any one of the claims 1-4 with a variation in kinematic viscosity less than 5% over a period of 1000 hours in a JCMAS HK test. A hydraulic fluid composition according to any one of the claims 1-5 with a variation in kinematic viscosity less than 2.5% over a period of 1000 hours in a JCMAS HK test. A hydraulic fluid composition according to any one of the claims 1-6 with an RPVOT as per ASTM D2272-02 measured, more than 600 minutes. A hydraulic fluid composition according to any one of the claims 1-7 with an RPVOT as per ASTM D2272-02 measured, more than 1000 minutes. A hydraulic fluid composition according to any one of claims 1-8 having a kinematic viscosity at 40 ° C of 10 to 800 mm ² / s. A hydraulic fluid composition according to any one of the claims 1-9, wherein the base lubricating oil at least one of the following properties: a) a molecular weight of 500-750; b) a molecular weight greater than 600; c) an autoignition temperature of at least 360 ° C; and d) biodegradability according to OECD 301D of> = 60%. A hydraulic fluid composition according to any one of the claims 1-10, wherein the base lubricating oil at least one Fischer-Tropsch base oil comprises and 5 to 50 wt .-% of at least one base lubricating oil selected from Vegetable oils, base lubricating oils of group I, II, III, IV and V as defined in the API Interchange Guidelines, and their mixtures. A hydraulic fluid composition according to any one of claims 1-8, wherein the base lubricating oil has at least one of the following properties: a) a kinematic viscosity at 100 ° C in the range of 1 to 15 mm ² / s; b) a Noack volatility which is less than the amount which results from the following equation: 900 × (kinematic viscosity at 100 ° C.) ^-2.8-15 ; c) an average molecular weight between 600 and 1100; d) an average degree of branching in the molecules between 6.5 and 10 alkyl branches per 100 carbon atoms; e) an autoignition temperature in ° C (AIT) greater than an AIT in ° C defined by the equation: 1.6 × (kinematic viscosity at 40 ° C, in mm ² / s) + 300; f) a traction coefficient smaller than the amount calculated by the equation: 0.009 × Ln (kinematic viscosity in mm ² / s) - 0.001, wherein the kinematic viscosity is the kinematic viscosity in the oil during the measurement of the traction coefficient. A hydraulic fluid composition according to any one of claims 1-12, which further comprises at least one of The following includes: pour point reducing blending components having an average degree of branching in the range of 6.5 to 10 alkyl branches per 100 carbon atoms; Polymethacrylates, polyacrylates, polyacrylamides, condensation products of halo-paraffin waxes and aromatic compounds, vinyl carboxylate polymers, terpolymers of dialkyl fumarates, vinyl esters of fatty acids and alkyl vinyl ethers, and mixtures thereof. A hydraulic fluid composition according to claim 1, wherein the base lubricating oil comprises a Fischer Tropsch base oil having a kinematic viscosity at 100 ° C between 6 mm ² / s and 20 mm ² / s; a kinematic viscosity at 40 ° C between 30 mm ² / s and 120 mm ² / s; a viscosity index between 150 and 165; a cold start viscosity in the range of 3000-50000 mPa · s at -30 ° C, 2000-20000 mPa · s at -25 ° C; a pour point in the range of -2 and -20 ° C; a molecular weight of 500-750; a density in the range of 0.820 to 0.840; a range of 92-95% for the paraffinic carbon; a range of 5-8% for the naphthenic carbon; Oxidizer BN of 30 to 50 hours and a Noack volatility in wt .-% of 0.50 to 5. Method for operating a hydraulic pump, in wherein a hydraulic fluid composition is used (i) 80-99.999% by weight of a base lubricating oil and (ii) 0.001-20 wt% of at least one additive package, wherein the base lubricating oil sequential numbers on carbon atoms, less than 10% by weight of naphthenic carbon in accordance with n-d-M, less than 0.10% by weight of olefins and less than 0.05% by weight of aromatics, more than 25% by weight of all Molecules with cycloparaffinic functionality and a Ratio of molecules with monocycloparaffin functionality to molecules with multicycloparaffin functionality greater than 10; and wherein the hydraulic fluid composition at least one of the JCMAS HK and JCMAS HKB 2005 standards Fulfills.