US3150089A

US3150089A - Highly basic magnesium containing additive agent

Info

Publication number: US3150089A
Application number: US15031A
Authority: US
Inventors: Mack W Hunt
Original assignee: Continental Oil Co
Current assignee: ConocoPhillips Co
Priority date: 1959-05-07
Filing date: 1960-03-31
Publication date: 1964-09-22
Anticipated expiration: 1981-09-22
Also published as: GB906208A; DE1271873B; BE602059A; NL251334A

Description

Sept. 22, 1964 M. w. HUNT HIGHLY BASIC MAGNESIUM CONTAINING Filed March 51 1960 IN MICRONS BQNVLLI WSNVHJ. .LNHOHHd ADDITIVE AGENT 2 Sheets-Sheet 1 WAVE LENGTH FIG.

INVENTOR.

MACK W. HU/VT ATTORNEY Sept. 22, 1964 M. W. HUNT HIGHLY BASIC MAGNESIUM CONTAINING ADDITIVE AGENT Filed March 51, 1960 STILL ugh] 2 Sheets-Sheet 2 PRIMARY EXTRACTOR TOWER OVERHEAD ALCOHOL H2O SOLVENT SECONDARY EXTRACTOR ALCOHOL H20 FIG. 2

ANHYDROUS ALCOHOL INVENTOR. MACK W. HUNT aywap ATTORNEY United States Patent 3,150,089 HIGHLY BASIC MAGNESIUM CONTAINING ADDITIVE AGENT Mack W. Hunt, Pouca City, Okla, assignor to Continental Oil Company, Ponca City, Okla, a corporation of Delaware Filed Mar. 31, 1960, Ser. No. 15,031 Claims. (Cl. 252-33) This invention relates to highly-basic magnesium-containing additive agents. More particularly, it relates to a process for dispersing =a magnesium-containing inorganic compound, which is magnesium hydroxide, magnesium carbonate, or mixtures thereof, in a non-volatile carrier. Another aspect of the invention relates to a process for preparing a magnesium .alkoxide-carbonate complex, said complex being used in preparation of the dispersion of the magnesium-containing inorganic compound. Still another ;aspect of the invention relates to the magnesium alkoxide-carbonate complex, itself.

The present application is a continuation-in-part of Serial No. 811,522, filed May 7, 1959, now abandoned.

In heavy-duty detergent type lubricating oil composi tions for use in diesel and like internal combustion engines, at least two requirements must be met by such oils (in addition to lubricity, stability, and the like) if a high degree of engine cleanliness is to be maintained. First, the oil must possess the power to disperse insolubles formed by fuel combustion or oil oxidation, or both; and second, the oil must be capable of neutralizing acidic lacquer precursors formed by either oil oxidation or interaction of the oil with sulfur acids produced from fuel combustion, or both of these conditions.

It is particularly desirable that lubricating oil com positions used in marine diesel engines have a high degree of basicity. This requirement is caused by the use of fuels having a high sulfur content, which, in turn, means a larger amount of acidic combustion prod ucts. Of course, it is possible to alleviate this prob lem through the use of lower sulfur fuels. However, the economics of the situation makes it desirable to use a high sulfur fuel in conjunction with a lubricating composition capable of neutralizing the acidic combustion products.

The compositions of the present invention are generally useful in lubricating compositions for use in internal combustion engines. They are also useful in corrosion inhibiting compositions and particularly in fuel compositions containing vanadium. Since the compositions ordinarily contain a large amount of excess basicity, they are especially useful in marine lubricating compositions.

Many attempts have been made heretofore to produce substances which possess an alkaline reserve whereby the acidic materials formed in lubricating oils during use may be neutralized. One proposed method is that described by Bergstrom in U.S. Patent Nos. 2,270,577 and 2,279,086 utilizing basic soaps. These basic soaps demonstrated a certain superiority, and further attempts were made to increase the b-asicity of such soaps. One of the earliest patents referring to these basic soaps or, as they were sometimes called, overbased soaps or metal complexes is U.S. Patent No. 2,418,894 to McNab. Other Workers in this field include Griesinger et al. (U.S. Patent No. 2,402,325). These patentees suggested the use of a neutralizing agent up to about 220 percent of the theoretical amount required for the complete neutralization of the acid from which the soap was made. The work of Griesinger et al. was followed by Campbell and Dellinger as described in their U.S. Patent No. 2,485,861. These particular patentees base their dis- 3,150,089 Patented Sept. 22, 1964 closure on the hypothesis that minor amounts of talkaline earth metal hydroxide or carbonate can be peptized by means of an oil mahogany sulfonate. Mertes in U.S. Patent No. 2,501,731 described a process whereby the normal soap is first formed and then an additional base combined therewith by a more or less simple mixing and heating operation followed by filtration. Utilizing the basic disclosure of Mertes, Asseff et al. in U.S. Patent No. 2,616,924 disclose a process whereby a much larger amount of metal or base may be combined with the normal soap, thus forming a complex which may be dispersed in a lubricating oil and, because of the excess metal present, possesses an alkaline reserve. The invention of Assefi et :al. is an improvement over the Mertes disclosure in that Asself et al. employed a so-called promoter. Generally, these promoters are alkylated phenols.

Van Ess et al. in U.S. Patent No. 2,585,520 disclose a process for the preparation of a basic salt by first combining in an anhydrous state the normal salt of the acidic material and an alcoholate of the desired metal. The mass is heat-treated for a substantial length of time, filtered, and then the alcoholate is hydrolyzed to the hydroxide for the purpose of providing a basic product.

Although the products produced by the methods described above possess an alkaline reserve suitable for neutralizing acidic contaminants, there are a number of disadvantages inherent in all of these processes. As one disadvantage, the formation of the complex involves a heating process over a rather extended period of time. Another disadvantage which is even more objectionable from an operating standpoint is that the sizes of the individual particles suspended in the oil vary greatly, from extremely small particles to particles which in many cases exceed ten microns in diameter. The larger size particles are objectionable for two reasons: (1) their presence imparts a haze to the oil and (2) it is generally conceded that, if the particles exceed five microns in diameter, the resulting product will have a certain abrasive action upon the metal bearings. Before use, the product therefore must be filtered. Obviously, filtration increases the cost of operation, and the larger particles retained on the filter must be discarded.

U.S. Patent No. 2,895,913 to Carlyle et al. discloses a process for preparing a stable dispersion of a basic magnesium-containing compound in a lubricating oil composition. In the process of these patentees, an alkanol insoluble magnesium alkoxide is formed by reacting magnesium with an excess of an alk-anol. The resulting magnesium alkoxide is then reacted with carbon dioxide to form an alkanol soluble magnesium alkoxide-carbon dioxide complex. The magnesium :alkoxide-carbon dioxide complex is admixed with a lubricating oil, an oilsoluble dispersing agent, and water. This admixture is heated to decompose the complex, remove the alkanol and obtain an oil-insoluble magnesium compound, wherein the particle size is less than 0.25 micron.

U.S. Patent No. 2,920,105 to Kluge et al. discloses a process for making oil-soluble hyperbasic alkaline earth metal sulfonates. The process of these patentees comprises formiug a reaction mixture of an oil-soluble normal alkaline earth metal sulfonate in a water immiscible organic medium and an alkaline earth metal lower alkoxy ethanolate in a vehicle of the corresponding alkoxy ethanol, the mole ratio of said alkoxy ethanolate to normal sulfonate being between about 0.5 :1 and about 7:1 or even higher, said normal sulfonate starting material con- ,taining not substantially more than about the stoichiometric amount of liquid Water needed to complete hydrolysis of the alkoxy ethanolate starting material to the corresponding alkaline earth metal hydroxide, stripping the mixture at temperatures of 225 and 450 F., bringing the total quantity of water introduced into the reaction mixture to an amount suflicient for obtaining complete liberation of the'combined alkoxy ethanol from the alkoxy ethanolate starting material, and terminating the stripping when substantially all of the alkoxy ethanol, vehicle and hydrolysis reaction product, has been expelled from the reaction mixture.

While the processes of Patents Nos. 2,920,105 and 2,895,913 are improved processes, as compared with other known processes, the process of the present invention has further advantages. This will be apparent from -a later discussion.

It is, therefore, a principal object of the present invention to provide a process for preparing a stable dispersion of a magnesium-containing, inorganic compound in a non-volatile carrier, which process obviates the disadvantages of the prior art processes.

Another object of the present invention is to provide a highly useful oil composition, utilizing such dispersion. Still another object of the present invention is to provide a process for preparing a magnesium alkoxide-carbonate complex which may be used in preparing a stable dispersion of a magnesium-containing inorganic compound in a non-volatile carrier.

Yet another object of the present invention is to provide, as a composition of matter, a magnesium alkoxidecarbonate complex. These and other objects and advantages of the invention will be apparent as the description proceeds.

Broadly stated, the present invention relates to a magnesium alkoxide-carbonate complex having the following formula:

Mg(0 omomon)z x(oo-ocmornon X where R is either a C to C alkyl group or an organic radical of the formula wherein R- is a C to C alkyl group, and x is from 0.5

to 1.5, preferably 0.75 to 1.0. This complex is particularly useful for preparing a stable dispersion of a basic, magnesium-containing, inorganic compound in a nonvolatile carrier.

Another aspect of the present invention relates to a process for preparing the oil-soluble magnesium alkoxidecarbonate complex. Broadly stated, the process comprises:

(A) Reacting magnesium with a glycol ether, which may be either a monoether of ethylene glycol or a monoether of diethylene glycol, to form a magnesium alkoxide (B) Reacting the magnesium alkoxide with carbon dioxide to form an oil-soluble magnesium alkoXide-carbonate complex.

Still another aspect of the present invention relates to a process for preparing a stable dispersion of a basic, magnesium-containing inorganic compound in a nonvolatile carrier, werein the process comprises:

(A) Admixing a glycol ether solution of an oil-soluble magnesium alkoXide-carbonate complex, an oil-soluble dispersing agent, a non-volatile carrier, and water in an amount which is a stoichiometric excess of that required to react with the magnesium alkoxide-carbonate complex,

(B) Hydrolyzing the magnesium alkoxide-carbonate complex to an oil-insoluble magnesium-containing inorganic compound, and then (C) Removing the volatile material.

A particularly important feature of this aspect of the present invention is that the oil-insoluble, magnesiumcontaining compound is in the form of particles having diameters of less than 0.25 micron.

Having broadly stated my invention, it is now convenient to discuss the advantages of the present invention as compared to the aforementioned patents to Kluge et al. and Carlyle et al. In addition, it may be well to discuss briefly wherein my invention differs from these particular patents. A principal advantage of the present invention is that dispersions having very high base numbers, in other words a very high degree of excess basicity, are obtained. As mentioned previously, these high-base number dispersions have a special utility in marine diesel lubricating oil compositions. I believe that these highbase number dispersions are obtained because of the particular intermediate used in my invention.

My invention differs from the teachings of the patents to Kluge et al. in several aspects. One of these is that my process employs a carbonated magnesium alkoxide, whereas Kluge et al. use magnesium alkoxide. Another is that my process uses a stoichiometric excess of water to hydrolyze the carbonated magnesium alkoxide, whereas Kluge et al. use not substantially more than the stoichiometric amount of water. Still another is that Kluge et al. use higher temperatures for the overbasing step than is necessary in my process.

Before proceeding with specific examples which illustrate my invention, it may be well to indicate, in general, the nature of the materials used, the more important operating conditions in the process, and the nature of the intermediate (magnesium alkoxide-carbonate complex).

MATERIALS USED The magnesium used in the process may be in form of bars, rods, turnings, or powder.

Suitable glycol ethers for use in the process include monoethers of ethylene glycol and monoethers of diethylene glycol. While any of these glycol ethers are suitable, generally I prefer not to use those containing above about 8 carbon atoms, since such glycol ethers have a high boiling point and require more heat for their removal. Preferred glycol ethers are the monoethyl ether of ethylene glycol and the monomethyl ether of ethylene glycol. These materials are available commercially under the trademarks Cellosolve and methyl Cellosolve. The monomethyl ether of diethylene glycol is available commercially under the trademark Carbitol.

The monoethers of ethylene glycol are also known as alkoxy alkanols, and more specifically as alkoxy etha nols. These materials have the generic formula ROCH CH OH where R is a C to C group. Similarly, the monoalkylether of diethylene glycol has the generic formula HOCH CH OCH CH OR, where R is a C to 0., alkyl group. I

A wide variety of non-volatile carriers may be used in my process. The principal requisite desired in the non-volatile carrier is that it will dissolve the dispersing agents used in the process. Examples of non-volatile carriers which may be used include mineral lubricating oil obtained by any of the conventional refining procedures, vegetable oils such as corn oil, cottonseed oil, castor oil, etc., animal oils such as lard oil, sperm oil, etc., and synthetic oils such as polymers of propylene, polyoxyalkylenes, polyoxypropylene, dicarboxylic acid esters such as esters of adipic and azelaic acids with alcohols such as butyl, 2-ethy1 hexyl and dodecyl alcohols, and esters of acids of phosphorus such as diethyl ester of decanephosphonic acid and tricresyl phosphate. If desired, the non-volatile carriers may be diluted with a solvent to reduce the viscosity. Suitable solvents include petro leum naphtha or hydrocarbons such as hexane, heptane, octane, benzene, toluene, or xylene.

A variety of oil-soluble dispersing agents may be used. Generic examples of suitable dispersing agents include the oil-soluble sulfonic acids, carboxylic acids, phosphorus sulfide-treated olefins, and metal salts thereof.

Preferred dispersing agents include the oil-soluble sulfonic acids, carboxylic acids, and metal salts thereof.

sulfonates which are suitable are oil-soluble and include alkyl sulfonates, alkaryl sulfonates, the so-called mahogany or natural soaps, and the like. The mahogany soaps include, particularly, the oil-soluble aromatic sulfonates from petroleum. Many of the aromatic sulfonates have cycloalkyl (i.e., naphthenic) groups in the side chains attached to the benzene ring. The mahogany soaps may include nonaromatic sulfonates produced in conventional sulfuric acid refining of lubricating oil distillates and from the industrial use of fuming sulfuric acid in the refining of petroleum. The industrial production of oil-soluble mahogany sulfonates from petroleum is well understood in the art and is described in the literature. Normally, the alkyl sulfonates require about 24 carbon atoms for oil solubility. The alkaryl sulfonates,

however, require an alkyl portion totaling only about 18 carbon atoms. To attain the requisite oil solubility, therefore, requires that the hydrocarbon portion of the sulfonate have a molecular weight between about 350 and 1,000. Preferably, this molecular weight is between 400 and 700. Particularly useful sulfonates include diwaxbenzene sulfonates, diwaxtoluene sulfonates, and postdodecylbenzene sulfonates. Postdodecylbenzene, which consists of monoalkylbenzenes and dialkylbenzeues in the approximate mole ratio of 2 to 3, has typical properties as follows:

Specific gravity at 38 C 0.8649

The wax used in making the wax aromatic sulfonate is obtained from different sources of crude petroleum oil. Various grades of paraffin wax are made with different melting points. The l26128 F. (52.2-53.3 C.) melting point wax is a mixture of organic compounds with the molecular weight averaging in the range of 330340. The average number of carbon atoms in this mixture of organic compound will be around 24. As the melting point of the wax decreases, the carbon content of the mixture will average as low as 18 or a little lower.

Other sulfonates which may be used in the process of this invention include, for example, monoand poly-wax substituted naphthalene sulfonates, dinonyl ifaphthalene sulfonates, diphenyl ether sulfonates, naphthalene disulfide sulfonates, diphenyl amine sulfonates, dicetyl thianthrene sulfonates, dilauryl beta-naphthol sulfonates, dicapryl nitro-naphthalene sulfonates, unsaturated paraffin wax sulfonates, hydroxy substituted parafiin wax sulfonates, tetra-amylene sulfonates, mono and polychloro-substituted paraffin wax sulfonates, nitrosoparaffin Wax sulfonates; cycloaliphatic sulfonates, such as laurylcyclo-hexyl sulfonates, monoand poly-wax substituted cyclo-hexyl sulfonates, and the like. The expression petroleum sulfonate is intended to cover all sulfonates derived from petroleum products.

Instead of using the foregoing sulfonates as such in the invention, we may also form those sulfonates in situ by adding the corresponding sulfonic acid to the mixture which then can be converted to the sulfonate by any convenient means.

Suitable carboxylic acids include naphthenic acids such as the substituted cyclopentane monocarboxylic acids, the substituted cyclohexane monocarboxylic acids and the substituted aliphatic polycyclic monocarbo xylic acids containing at least 15 carbon atoms. Specific examples in clude cetyl cyclohexane carboxylic acids, dioctyl cyclopentane carboxylic acids, dilauryl decahydronaphthalene and stearyl-octahydroindene carboxylic acids, and the like, and oil-soluble salts thereof. Suitable oil-soluble fatty acids are those containing at least 8 carbon atoms. For producing the object of this invention in liquid form We prefer fatty acids which are liquids at ambient temperatures down to about 15 C. Specific examples include 2-ethyl hexanoic acid, pelargonic acid, oleic acid, palmitoleic acid, linoleic acid and ricinoleic acid. Naturally occurring mixtures of predominately unsaturated fatty acids, such as tall oil fatty acids, are particularly suitable. Similarly, as in the case of the sulfonates, instead of using the foregoing carboxylic acid soap as such, we may form those soaps in situ by adding the corresponding carboxylic acid to the mixture.

The phosphorus sulfide treated olefins (by the term olefins We means to include also olefin polymers, e.g., polyisobutylene) and their oil-soluble metal salts which are suitable for use include those customarily used in lubricating oil formulations as corrosion inhibitors and/ or detergents. Specifically, they include the potassium-polyisobutylene-phosphorus sulfide products described by US. Patent 2,316,080, issued on April 6, 1943, to Loane and Gaynor, and a similar material containing no metal made by addition of a phosphorus sulfide to Wax olefins, as described in US. Patent 2,516,119, issued on July 25,

0 1950, to Hersh. This latter preferred material is made by first forming wax olefins from paraffin waxes by halogenation and dehydrohalogenation and subsequently treat ing the olefins with a phosphorus sulfide, preferably phosphorus pentasulfide. Another teaching of the preparation of phosphorus sulfide treated olefins is Patent No. 2,688,612, issued September 7, 1954, to Watson.

PROCESS CONDITIONS The process conditions used in the preparation of the magnesium alkoxide-carbonate complex will now be discussed. The glycol ether employed should have a water content of less than about 0.5 percent. Otherwise, there is a tendency for the reaction to be inhibited. The amount of the glycol ether used in the process can be varied over wide limits. The amounts used, however, should be in excess over that required to react with the magnesium. Stated another W21 I prefer to use an amount which is sufiicient to dissolve the magnesium alkoxide-carbonate complex to give a final concentration of magnesium in the solution of between about 5 to 8 percent. Satisfactory results can be obtained with the magnesium content varying within the range of about 1 to 10 percent. Since the reaction of magnesium and the glycol ether is strongly exothermic (heat of reaction approximates 70,000 B.t.u. per pound-mole), it is necessary to provide cooling on the reaction vessel in order to control the reaction. The reaction is generally kept at reflux temperature until complete.

In the conversion of the magnesium alkoxide (the reaction product of the magnesium and the glycol ether) to the magnesium alkoxide-carbonate complex, I have found it best to employ from about 0.5 to about 1.5, preferably from about 0.75 to about 1.0, moles of carbon dioxide per mole of magnesium alkoxide. I have found that a lower ratio gives a gel formation, whereas a higher ratio gives inorganic insolubles and more viscous products.

The preparation of the dispersion of the magnesiumcontaining inorganic compound will now be discussed. in this step an admixture is formed of the magnesium alkoxide-carbonate complex, the non-volatile carrier, the

tions.

dispersing agent, and the water. The amount of the different components used in my process can be varied widely. As an example, the oil-soluble dispersing agent varies from about 20 to about 55 percent of the total composition, the non-volatile carrier varies from about 40 to 76 percent, and the amount of the magnesium-containing inorganic compound varies from about 3.0 to 30 percent. The latter could probably be more accurately stated as to magnesium content. In this case, the amount of the magnesium in the final composition varies from about 1.24 to about 9.4 percent. All percentage figures given above are by weight.

The hydrolysis reaction is as follows:

It is thus apparent that the stoichiometric requirement is 2 moles of Water per mole of magnesium alkoxidecarbonate complex. I have found that a stoichiometric excess must be employed with a suitable range being from about 2.50 to about 4.50 moles of water per mole of alkoxide-carbonate complex, and with a preferable range being from about 2.8 to about 3 .5 moles.

In the previous paragraph, I have shown that a stoichiometric excess of water must be present at all times in the hydrolysis step. This is true in both a batch and continuous process. It is not necessary that all of the water he added to the reaction vessel prior to the addition of the magnesium alkoxide-carbonate complex, however, in adding the Water and magnesium alkoxide-carbonate complex to the reaction vessel, there must always be a stoichiometric excess of water in the reaction vessel. Otherwise, a severe gel formation is encountered.

The overbasing step (that is, the addition of the magnesium intermediate to the dispersing agent solution) is conducted over a wide range of temperatures, generally at about 25 to about 100 C., and more preferably in the range of about 35 to about 65 C. Temperatures outside the broad range are not used generally since they can lead to gel formation or the formation of inorganic insolubles.

Following the hydrolysis, the volatile materials (alcohol, solvent, and unreacted water) are removed by distillation.

During the latter stages of the distillation, it is often desirable to employ gas blowing to facilitate solvent removal. When it is desired to convert the majority of the remaining magnesium hydroxide to magnesium carbonate, carbon dioxide is used for blowing. When it is desired to leave the majority of the dispersoid as magnesium hydroxide, an inert gas, for example, nitrogen and natural gas, is used. The removal of the volatile solvent leaves a bright fluid product which requires no additional filtration or centrifugation.

The relative amounts of the dilferent components employed in the process are dependent upon the desired percent actives and the base numbers of the final composi- (The term percent active refers to the amount of the dispersing agent present in the composition.) These variations are tabulated below for typical sulfonate preparations:

Table I 20% active 55% active 30% active 50 B.N. 60 B.N. 400 B.N.

Percent Mg Sulfonate 20 55 30 Percent MgCOs 3. 75 3. 75 30 Percent oil 76. 25 41. 25 40 Percent sulfonic acid 19. 5 53. 6 29. 2 Percent Mg as sulfonate. 0. 5 1. 4 0. 8 Percent Mg as MgC 03". 1.1 1.1 8. 6 Percent total Mg 1. 6 2. 5 9. 4 Range percent Mg snlfonate to 55% Range percent MgC Oa. 3. 75% to 30% Range percent 00.... 40% to 76. Range percent Mg- 1. (3% to 9.4%

'perchloric acid in glacial acetic acid as the titrant.

8 THE INTERMEDIATE 'The'terms magnesium alkoxide-carbonate complex and magnesium intermediate are used herein synonymously. As far as is known, the magnesium alkoxidecarbonate complexes derived from glycol ethers have not been prepared heretofore and they are, therefore, considered to be new compositions of matter.

The magnesium intermediates correspond to the'fol lowing general formula:

where R is either a C to C alkyl group or a monoether of the formula CC-OR', wherein R is a C to C alkyl group and x is from 0.5 to 1.5, preferably from 0.75 to 1.0.

The magnesium intermediates are soluble in the substituted glycol ether from which they are derived. In addition, the magnesium intermediates have a solubility in other hydrocarbon solvents corresponding to that of the substituted glycol ether from which they are derived. For example, the magnesium intermediate prepared from methyl Cellosolve has a solubility in benzene and hexane correspond ng to that of methyl Cellosolve in the solvents. Elsewhere herein we have used the term oil-soluble as applied to the magnesium intermediates. This term should be clarified somewhat. The magnesium intermediates of this invention (and this includes those of all suitable glycol ethers listed herein) exhibit solubility in hydrocarbon solvents, both aromatic and non-aromatic. They also have a finite solubility in pale oil. The higher molecular weight magnesium intermediates are soluble in the more viscous lubricatingoil fractions, such as bright stock. The properties of several examples of magnesium intermediates prepared from methyl Cellosolve are shown in Table II below.

Table II.Pr0pcrtics of Intermediate Prepared from Methyl Cellosolve Sample No A B o D n r o X 1 1.12 1.08 1.11 0.98 0.82 1.42 0 Percent Mg 6.38 7.30 7. 72 8.03 7. 75 7. 46 8. 51 Percent 00; 3 12. 14. 32 15. 46 14. 22 ll. 57 19. 20 0 Viscosity at:

F., cs 36.40 11.10 112.10 191. 10 79. 80 654. 00 33. 20

210 F., cs 4. 97 3. 80 20. 20 15. 30 9.08 28. 50 4. 94 Specific gravity at 60 F. 1635 1.1320 1.2019 1. 2027 1.1852 1. 2283 1. 1218 Cold test, Fl -26 40 +20 4 0 1 X is calculated for the following formula Mg(0CHzCHgOCHsli-JO-Ql-OCHzCHzO CH3);

2 Determination made by titrimetric procedure using ethylene diamine tetraacetate.

3 Determination made by acid decomposition and absorption of evolved 002.

* ASTM Method No. 13-445.

5 ASTM Method No. D-1298.

9 AS'IM Method N0. ID-97.

An infrared spectrum of a magnesium alkoxide-carbonate complex prepared in accordance with my process is included as FIGURE 1. In this spectrum the band at about 6.08 micron is due to the carbonate structure. The band at about 2.9 microns is due to the hydroxyl group, which is present in the solvent (i.e., methylether of ethylene glycol). The band at about 3.45 microns is due to carbon-hydrogen linkage. The band at about 8.8 microns to about 9.5 microns is due to ether linkage. and to alcohol. Both of the latter bands (3.45 microns and 8.8 to 9.5 microns) are due to both the solvent and the magnesium intermediate.

All the base numbers of the products of this invention were determined by the acetic acid titration method which utilizes glacial acetic acid as the solvent and a solution of The method is especially adapted for the determinations of this type, since equilibria are obtained rapidly. The

procedures for carrying out acetic acid titrations are generally outlined in Analytical Chemistry, volume 23, No. 2, February 1951, page 337, and volume 24, No. 3, March 1952, page 519. As used herein, base number refers to milligrams of potassium hydroxide per gram of sample.

In order to disclose the nature of the present invention still more clearly, the following illustrative examples will be given, in which parts used are parts by weight. In the examples, the numerical value preceding pale oil designates the s.s.u. value at 100 F.

EXAMPLE 1.PREPARATION OF MAGNESIUM METHOXY ETHOXIDE-CARBONATE A reaction vessel equipped with a thermometer and two reflux condensers was charged with 20.5 parts of magnesium and 350 parts of monomethyl ether of ethylene glycol. The contents of the reactor were initially heated to 50 C. to initiate the reaction. After the reaction was initiated, the heat of reaction was suflicient to maintain the temperature within the range of 70 to 80 C. The reaction was allowed to proceed to completion during which time it became quite vigorous. After the reaction had subsided, the product was filtered. After filtering, the filtrate so obtained was blown with carbon dioxide, forming magnesium methoxy ethoxide-carbonate. Analysis showed the solution to contain 6.36 percent magnesium. Filtration is only necessary to remove the small amount of impurities present in the original magnesium. If pure magnesium is used, filtration is unnecessary.

EXAMPLE 2.PREPARATION OF MAGNESIUM ETHOXYETHOXIDE-CARBONATE The preparation of this product was carried out in the same manner as in Example 1 with the exception that the monoethyl ether of ethylene glycol was used instead of the monomethyl ether of ethylene glycol. The resulting solution contained 4.84 percent magnesium.

In both Examples 1 and 2, the yields of the magnesium compound were quantitative.

EXAMPLE 3 To a reaction vessel equipped with a stirrer, dropping funnel, thermometer, and reflux condenser were charged 171.4 parts of postdodecylbenzene sulfonic acid, 1,218.9 parts of naphtha, 304.3 parts of 170 pale oil, and 52.9 parts or" water (1.4 times the stoichiometric requirement). Stirring was commenced, and 493.5 parts of a solution of magnesium methoxy ethoxide carbonate of Example 1 after diluting with an additional quantity of monomethyl ether of ethylene glycol to give a solution having a concentration of 5.53 percent magnesium was added over a period of 3 minutes. The reaction mixture was refluxed for a period of minutes at a temperature varying from 60 to 70 C., after which volatile components were removed by distillation. The reaction mixture was then blown with carbon dioxide while heating at a temperature of 150 C. for a period of minutes, which removed all unreacted Water and monoethyl ether of ethylene glycol. Five hundred ninety-six and 8 tenths parts of a final product was obtained, which was bright, clear, and fluid. It had a base number of 200.

The postdodecylbenzene sulfonic acid used in this example and in Example 4 was the sulfonic acid produced by sulfonating a mixture of monoalkyl benzenes and dialkyl benzenes. This product is described further in U.S. Patent 2,861,951, granted to R. L. Carlyle dated November 25, 1958.

EXAMPLE 4 To the reaction vessel described in Example 3 was added 12.8 parts of postdodecylbenzene sulfonic acid, 17.64 parts of 170 pale oil, 9.32 parts of water (1.75 times the stoichiometric requirement), and 178.9 parts of naphtha. The reaction mixture was heated to C., and then 97.10 parts of the magnesium ethoxy ethoxide carbonate prepared in Example 2 was added thereto over a period of 45 minutes. Prior to the addition of the magnesium ethoxy ethoxide carbonate, it was diluted with an additional quantity of monoethyl ether of ethylene glycol so as to reduce the magnesium content to 4.06 percent. The reaction mixture was refluxed for a period of 30 minutes, cooled to room temperature, and blown with carbon dioxide for 5 minutes. Twenty nine parts of water was then added, and 50 percent of the original monoethyl ether of ethylene glycol was separated from the reaction mixture through the formation of two layers. The volatile components were removed by distillation. When the temperature reached 150 C., the reaction mixture was blown with carbon dioxide to eflect the complete removal of unreacted monoethyl ether of ethylene glycol and water. Fifty three and 4 tenths parts of a bright, clear, and fluid product was obtained. It had a base number of 300.

The second addition of Water (29 parts) above was not made to hydrolyze the magnesium intermediate. It was added at this point to facilitate phase separation of volatile components. However, it does illustrate the relative insensitivity of the system to the amount of water.

EXAMPLE 5 To a reaction vessel equipped with a stirrer, dropping funnel, thermometer, and reflux condenser were charged 60.0 part sof a tall oil fatty acid (acidity=3.39 milliequivalents per gram), 92.5 parts of pale oil, 290 parts of water (1.5 times the stoichiometric requirements) and 150.0 parts of xylene (commercial). This mixture was heated to 47 C. and 193 parts of magnesium methoxy ethoxide-carbonate solution (8.03 percent Mg; 11.91 percent CO was added over a 25-minute period. The reaction mass was heated to 150 C. to remove volatile components. It was then blown with carbon dioxide for 20 minutes while maintaining the temperature at about 150 C.

The product was clear, stable, and very fluid. It had an acetic base number of 335 and contained 7.26 percent magnesium by weight. The material used was Crofatol 5 (from Crosby Chemicals, Inc.), which is a distilled tall oil fatty acid having the following properties:

Fatty acids, percent 90.0 Rosin acid 6.0 Gardner color 6-7 Acid number 190 Saponification value 192 Unsaponifiable, percent 4.0 Iodine value Titre C 5 Composition of fatty acid present- Saturated fatty acid, percent 3 Oleic acid, percent 51 Linoleic acid, percent 46 EXAMPLE 6 Example 5 was repeated with the exception that petroleum naphtha was substituted for the xylene. Similar results were obtained.

EXAMPLE 7 To a reaction vessel equipped with a stirrer, dropping funnel, thermometer, and reflux condenser were charged 100 parts of a mixture consisting of 57.5 percent (weight) of a phosphorus sulfide-treated olefin and 42.5 percent (weight) of 100 pale oil, 77.4 parts of 100 pale oil, 9.2 parts of water (1.5 times the stoichiometric: requirement) and 100 parts of xylene (commercial). This mixture was heated to 52 C. and 62.0 parts of magnesium methoxy ethoxide-carbonate solution (8.03 percent Mg; 11.91 percent CO was added over a 12-minute period. The reaction mass was heated to C. to remove volatile components. It was then blown with carbon 11 dioxide for 15 minutes while maintaining the temperature at about 150 C.

The product was very clear, stable, and fluid. It had an acetic base number of 57 and contained 1.3 percent oil. It had the following analysis:

Acidity, milliequivalents per gram 0.61 Combining weight (approx) 950 Percent phosphorus 1.85 Percent sulfur 0.89

While the preceding examples have shown batch operation of our process, the process is adaptable to corn tinuous operation, or a combination of batch and continuous operation. In order to illustrate the adaptation of our process to commercial operation, a fiow diagram of such an operation is shown in FIGURE 2. Referring now to FIGURE 2, the following is a description thereof.

The reactor 1 is equipped with means 2 for providing cooling or heating, steam is supplied through line 3, while colder water is supplied through line 4, to the heating or cooling means 2. Magnesium metal enters the reactor 1 through line 5 while the alcohol enters through line 6. The hydrogen produced in the reaction leaves the reactor 1 by way of line 7, passing through cooling coils 8 to the vent 9. The cooling coils 8 condense the alcohol present in the hydrogen, with the alcohol returning to reactor 1 by way of line 7. The magnesium alkoxide and the impurities (which come from the impurities in the magnesium) leave reactor 1 by way of line 10, go through pump 11, then through line 12 to the filter 13. The filter 13 removes the impurities, and the magnesium alkoxide then goes through line 14 to the eductor 15. Carbon dioxide is provided to the eductor by line 16. The carbonated magnesium alkoxide leaves the eductor 15 through line 17, passes through the cooling unit 18 and then goes into line 17a. A portion of the carbonated magnesium alkoxide goes from line 17a to line 19, where it is returned to line 10. This portion again goes through line 10, pump 11, line 12, filter 13, line 14, eductor 15, line 17, cooling unit 18, and finally line 17a. The purpose of the recirculation at this point is to provide cooling for the carbonation step. The combined carbonated magnesium alkoxide (or magnesium intermediate) then goes through line 20 to a storage tank 21.

For simplicity, vessel 23 is referred to as a neutralizer, although overbasing also occurs in this step. The neutralizer 23 is provided with agitation means 28 and a carbon dioxide vent 29. The magnesium complex goes from storage tank 21 through line 22 to the neutralizer 23. The sulfonic acid solution (comprising sulfonic acid, nonvolatile carrier, and hydrocarbon solvent) enters the neutralizer 23 through line 27. Additional nonvolatile carrier (or diluent oil) enters the neutralizer 23 through line 26. Tower overhead, containing about 65 percent water and about 35 percent alcohol, enters the neutralizer 23 through line 24. Additional water for makeup and use in the neutralizer 23 is provided by line 25 which connects to line 24. Carbon dioxide from line 31 goes through line 32 to both the neutralizer 23 and the still 33. The admixture passes from the neutralizer 23 through line to the still 33. An external heat source 37 is used for heating the admixture in the still 33. Recirculation through the heat source 37 and still 33 is provided by

lines

34, 36, and 38 and pump 35. Carbon dioxide (or other gas, as desired) is provided from line 31 through line 32 to the still 33. The product goes from line 36 through line 39 to storage 40.

The still overhead, containing water, alcohol, and hydrocarbon solvent, passes from the still 33 through line 41 to a primary extractor 42. Tower overhead from storage tank 43 enters the primary extractor 42 through line 44. The solvent layer, containing some alcohol, passes from the primary extractor 42 through line 45 to a secondary extractor 47. Tower overhead also enters the secondary extractor 47 through line 48. Hydrocarbon solvent, essentially free of alcohol, leaves the secondary extractor through line 49 and is available for reuse. A mixture of alcohol and water leaves the secondary extractor and goes by way of line 50 to tower overhead storage 43. The alcohol-water layer from the primary extractor 42 goes through line 46 to a fractionating tower 51. Essentially anhydrous alcohol leaves the tower through line 53 and the tower overhead goes through line 52 to tower overhead storage 43.

The following example is provided in order to illustrate our invention in a commercial size installation. The term parts in this particular example refers to pounds per hour. Three hundred eighty parts of magnesium bars (99.8 percent pure) and 3,716 parts of monomethyl ether of ethylene glycol were charged to a reactor. This resulted in a solution comprising 1,334 parts of monomethyl ether of ethylene glycol and 2,723 parts of mag nesium methoxy ethoxide. This solution was then carbonated with 687 parts of carbon dioxide. The yield from the carbonation step was 3,409 parts of magnesium methoxy ethoxide-carbonate complex and 1,334 parts of monomethyl ether of ethylene glycol. In the neutralizing-overbasing step, the following were charged to the re action vessel:

Sulfonic acid solution Parts Sulfonic acid 1,526 Oil 1,522 Hexane 3,492 Total sulfonic acid solution 6,540 Diluent oil 951 Magnesium complex solution (from above) 4,743 Make-up water 260 Tower overhead (water and monomethyl ether of ethylene glycol) 759 The total amount of water used was 1.5 times the stoichiometric requirement.

After completion of reaction, the volatile materials were removed by heating to about C. Six hundred eighty three parts of carbon dioxide were used for carbonating and stripping the product. A yield of 5,212 parts of 30 percent active, approximately 300 base number product, was obtained.

The additive agent of the present invention can be used in the range of about 1 to about 20 percent (by weight) in motor lubricating oils, with a preferable range being from about 3 to about 6 percent. When used in marine diesel oils, the suitable range is about 5 to about 25 percent (by weight), with the preferable range being about 10 to about 20 percent. The amount of additive required is dependent on a number of factors, such as, intended use, sulfur content of the fuel, and amount and type of other additive agentsused. The determination of the amount and the development of specific formulations containing the additive agent of my invention is within the skill of those trained in the art.

While particular embodiments of the invention have been described, it will be understood, of course, that the invention is not limited thereto, since many modifications may be made; and it is, therefore, contemplated to cover by the appended claims any such modifications as fall within the true spirit and scope of the invention.

The invention having thus been described, what is claimed and desired to be secured by Letters Patent is:

1. The process of preparing a stable dispersion of a basic, magnesium-containing, inorganic compound in a non-volatile carrier, said inorganic compound being present in the form of particles having a diameter not exceeding about 0.25 micron, said process comprising:

(a) admixing a glycol ether solution of an oil-soluble magnesium alkoxide-carbonate complex, said complex having been prepared from a glycol ether having not more than 8 carbon atoms, an oil-soluble dispersing agent, liquid lubricating oil, and water in an amount in excess of the stoichiometric requirement for hydrolysis of said magnesium alkoxide-carbonate complex,

(2;) hydrolyzing the magnesium alkoxide-carbonate complex to an oil-insoluble magnesium-containing inorganic compound, and then (c) removing the volatile material,

(d) said process being characterized further in that the magnesium alkoxide-carbonate complex of step (a) is prepared by a process comprising:

(1) reacting magnesium with a glycol ether having not more than 8 carbon atoms to form a magnesium alkoxide.

(2) reacting the magnesium alkoxide with from about 0.5 to about 1.5 moles of carbon dioxide per mole of said magnesium alkoxide to form a magnesium alkoxide-carbonate complex.

2. The process of claim 1 characterized further in that said process is conducted as a batch operation.

3. The process of claim 1 characterized further in that said process is conducted as a continuous operation.

4. The process of claim 1 characterized further in that said process is conducted as a combination of batch and continuous operation.

5. The process of claim 1, characterized further in that the oil-soluble dispersing agent is present in the range of about to about 55 percent (weight), the liquid lubrieating oil in the range of about to about 76 percent (weight), and the magnesium-containing inorganic compound in the range of about 3 to about 30 percent (weight) of the total composition.

6. The process of claim 5 wherein the dispersing agent is selected from the group consisting of oil-soluble sulfonic acids, carboxylic acids, phosphorus sulfide treated olefins, and metal salts thereof.

7. The process of claim 6 wherein the dispersing agent is an oil-soluble sulfonic acid.

8. The process of claim 6 wherein the dispersing agent is an oil-soluble metal sulfonate.

9. The process of preparing a stable dispersion of a basic, magnesium-containing, inorganic compound in a non-volatile carrier, said inorganic compound being present in the form of particles having a diameter not exceeding about 0.25 micron, said process comprising:

(a) admixing a glycol ether solution of an oil-soluble magnesium alkoxide-carbonate complex, an oil-soluble dispersing agent, a non-volatile carrier which is a liquid lubricating oil, and from about 2.5 to about 4.5 moles of water per mole of said magnesium alkoxide-carbonate complex,

(1)) hydrolyzing the magnesium alkoxide-carbonate complex to an oil-insoluble magnesium-containing inorganic compound, and then (c)removing the volatile materials,

(at) said process being further characterized in that the magnesium alkoxide-carbonate complex of step (a) is prepared by a process comprising:

( 1) reacting magnesium with a glycol ether selected from the group consisting of monoethers of ethylene glycol having not more than 8 car bon atoms and monoethers of diethylene glycol having not more than 8 carbon atoms, to form a magnesium alkoxide,

10. The process of claim 9, characterized further in that the oil-soluble dispersing agent is present in the range of about 20 to about 55 percent (weight), the liquid lubricating oil in the range of about 40 to about 76 percent (weight), and the magnesium-containing inorganic compound in the range of about 3 to about 30 percent (weight) of the total composition.

11. The process of claim 10 wherein the dispersing agent is an oil-soluble sulfonic acid.

12. The process of claim 10 wherein the dispersing agent is a metal salt of an oil-soluble sulfonic acid.

13. The process of claim 10 wherein the dispersing agent is an oil-soluble carboxylic acid.

14. The process of claim 10 wherein the dispersing agent is an oil-soluble metal salt of a carboxylic acid.

15. The process of claim 10 wherein the dispersing agent is an oil-soluble phosphorus sulfide-treated olefin.

16. The process of claim 10 wherein the dispersing agent is an oil-soluble metal salt of a phosphorus sulfidetreated olefin.

17. The process of claim 10 wherein the reaction mixture is blown with carbon dioxide during the removal of the volatile materials.

18. The process of preparing a stable dispersion of a basic, magnesium-containing, inorganic compound in a mineral lubricating oil, said inorganic compound being present in the form of particles having a diameter not exceeding about 0.25 micron, said process comprising:

(a) admixing a glycol ether solution of an oil-soluble magnesium alkoxide/carbonate complex, a dispersing agent selected from the group consisting of postdodecylbenzene sulfonic acid and metal salts of postdodecylbenzene sulfonic acid, a mineral lubricating oil, and from about 2.5 to about 4.5 moles of water per mole of said magnesium alkoxide-carbonate complex,

(b) hydrolyzing the magnesium alkoxide-carbonate complex to an oil-insoluble magnesium-containing inorganic compound, and then (0) removing the volatile materials,

(d) said process being further characterized in that (1) the glycol ether of the glycol ether solution is a monoether of ethylene glycol having not more than 8 carbon atoms, and

(2) the oil-soluble magnesium alkoxide-carbonate complex is prepared by reacting magnesium metal with monoether of ethylene glycol having not more than 8 carbon atoms, followed by passing from about 0.5 to about 1.5 moles of carbon dioxide per mole of magnesium alkoxide through the reaction mixture.

19. The process of claim 18, characterized further in that the dispersing agent is present in the range of about 20 to about 55 percent (Weight), the mineral lubricating oil in the range of about 40 to about 76 percent (weight) and the magnesium-containing inorganic compound in the range of about 3 to about 30 percent (weight) of the total composition.

20. The process of preparing a magnesium alkoxidecarbonate complex, said process comprising:

(a) reacting magnesium with a glycol ether having from 3 to 8 carbon atoms to form a magnesium alkoxide, and

(12) passing from about 0.5 to about 1.5 moles of carbon dioxide per mole of magnesium alkoxide through the mixture.

21. The process of claim 20 wherein the glycol other is the monomethyl ether of ethylene glycol.

22. The process of claim 20 wherein the glycol ether is the m-onoethyl ether of ethylene glycol.

23. As a new composition of matter, a magnesium alkoxide-carbonate complex having the following formula:

wherein R is a C to C alkyl group, and wherein x is a number varying from 0.5 to 1.5.

24. The process of preparing a stable dispersion of a basic, magnesium-containing, inorganic compound in a non-volatile carrier, said inorganic compound being present in the form of particles having a diameter not exceeding about 0.25 micron, said process comprising:

(a) adding a glycol ether solution of an oil-soluble magnesium alkoxide-carbonate complex, said complex having been prepared from a glycol ether having not more than 8 carbon atoms, to an admixture comprising an oil-soluble dispersing agent, liquid lubricating oil, and water in an amount which is a stoichiometric excess of that required for hydrolysis of said magnesium alkoxide-carbonate complex,

(b) hydrolyzing the magnesium alkoxide-carbonate complex to an oil-insoluble magnesium-containing inorganic compound, and then (c) removing the volatile material,

16 (d) said process being characterized further in that the magnesium alkoxide-carbonate complex of step (a) is prepared by a process comprising:

(1) reacting magnesium with a glycol ether having not more than 8 carbon atoms to form a magnesium alkoxide,

25. The process of claim 24, characterized further in that the oil-soluble dispersing agent is present in the range of about 20 to about 55 percent (weight), the liquid lubricating oil in the range of about 40 to about 76 percent (weight), and the magnesium-containing inorganic compound in the range of about 3 to about percent (weight) of the total composition.

References Cited in the file of this patent UNITED STATES PATENTS 2,695,910 Asseff et al Nov. 30, 1954 2,895,913 Carlyle et al. July 21, 1959 2,920,105 Kluge et a1. Jan. 5, 1960 3,006,847 Wiley et a1. Oct. 31, 1961 3,057,896 Schlicht et al. Oct. 9, 1962 3,067,018 Voorhecs Dec. 4, 1962

Claims

1. THE PROCESS OF PREPARING A STABLE DISPERSION OF A BASIC, MAGNESIUM-CONTAINING, INORGANIC COMPOUND IN A NON-VOLATILE CARRIER, SAID JINORGANIC COMPOUND BEING PRESENT IN THE FORM OF PARTICLES HAVING A DIAMETER NOT EXCEEDING ABOUT 0.25 MICRON, SAID PROCESS COMPRISING: (A) ADMIXING A GLYCOL ETHER SOLUTION OF AN OIL-SOLUBLE MAGNESIUM ALKOXIDE-CARBONATE COMPLEX, SAID COMPLEX HAVING BEEN PREPARED FROM A GLYCOL ETHER HAVING NOT MORE THAN 8 CARBON ATOMS, AN OIL-SOLUBLE DISPERSING AGENT, LIQUID LUBRICATING OIL, AND WATER IN AN AMOUNT IN EXCESS OF THE STOICHIOMETRIC REQUIREMENT FOR HYDROLYSIS OF SAID MAGNESIUM ALKOXIDE-CARBONATE COMPLEX, (B) HYDROLYZING THE MAGNESIUM ALKOXIDE-CARBONATE COMPLEX TO AN OIL-INSOLUBLE MAGNESIUM-CONTAINING INORGANIC COMPOUND, AND THEN (C) REMOVING THE VOLATILE MATERIAL, (D) SAID PROCESS BEING CHARACTERIZED FURTHER IN THAT THE MAGNESIUM ALKOXIDE-CARBONATE COMPLEX OF STEP (A) IS PREPARED BY A PROCESS COMPRISING: (1) REACTING MAGNESIUM WITH A GLYCOL ETHER HAVING NOT MORE THAN 8 CARBON ATOMS TO FORM A MAGNESIUM ALKOXIDE. (2) REACTING THE MAGNESIUM ALKOXIDE WITH FROM ABOUT 0.5 TO ABOUT 1.5 MOLES OF CARBON DIOXIDE PER MOLE OF SAID MAGNESIUM ALKOXIDE TO FORM A MAGNESIUM ALKOXIDE-CARBONATE COMPLEX.