US2348715A - Slushing composition - Google Patents

Description

' Patented May 1 6, 1944 T OFFICE SLUSHING CDMPOSITION Elmer Wade Adams.

George W. Flint, Chi

Hammond, Ind., n, 111., a sisnors to and Standard Oil Company, Chicago, 111., a corporation of Ind No Drawing. Application June 25, 1941, Serial No. 399,674

. (Cl. 106-t14) 21 Claims.

This invention relates to improvements in rust preventive compounds, otherwise known as slushing compounds, and more particularly to petroleum rust preventives or slushing compounds.

Metal surfaces whenever possible are protected from corrosion by a coating of some kind. In general, two types of protective coatings have been employed, namely permanent and temporary coatings. Under the first class are included oxide coatings, phosphate coatings, heat bluings, coatingsof metals such as zinc, cadmium, chromium, etc. and paints, varnishes, enamels and other non-metallic materials which form dry hard films. In the. second class of protective coatings, which are of thetype which must at some time be readily removed from the surfaces they are protecting, are those products prepared from petroleum oil and/or petroleum products such as lubricating oils, parafiin oils, petroleum naphthas, cylinder stocks, black oils, petrolatums, greases, asphalts, waxes, etc. While practically all such petroleum products give satisfactory protection under certain conditions, many such petroleum products have added thereto rust and/or corrosion inhibitors for added protection. For example, soaps of preferentially oil-soluble sulfonic acids derived from the sulfuric acid treat ment of petroleum oils have been added to slushing compounds, as exemplified by United States Patents Nos. 1,630,101 and 1,795,993, which dis close broadly the use of soaps of oil-soluble sulfonic acids derived from petroleum oils in slushing compounds and in slushing greases respectively.

While the soaps of preferentially oil-soluble sulfonic acids derived from the sulfuric acid treatment of petroleum'oil are generally effective tarnishing soap of an oil-soluble sulfonic acid derived from petroleum oils.

Other objects and advantages of the invention will become apparent as the description thereof proceeds.

Heretofore, it had been the general belief that the soaps of preferentially oil-soluble sulfonic acids obtained by the treatment of petroleum oils with sulfuric 'acid were of the same type, and therefore were equally effective as inhibitors for the prevention of corrosion and/or the formation of rust. We have now discovered that contrary to the general belief, there is a marked difference in the corrosion inhibiting properties of soaps of preferentially oil-soluble sulfonic acids 'obtained from oils under various treating conditions. We have discovered that the formation and/ or development of tarnish and discoloration upon metal surfaces treated with slushing compounds can be eliminated by employing the soaps of preferentially oil-soluble sulfonic acids derived from a particular sulfuric acid treatment of petroleum oil distillates; .namelythe soaps of the preferentially oil-soluble sulfonic acids derived by treating distillates of from about 70 seconds to about 500 seconds or higher, andpreferably from about 200 seconds to about 400 seconds Saybolt Universal ,viscosity at 100 F. with from about 6 to about 9 pounds, and preferably from about 7 to about 8 pounds of c'oncentrated sulfuric acid,

preferably fuming sulfuric acid, per gallon of oil.

The method of obtaining these-"desirable soaps of preferentially oil-soluble sulfonic acids dein inhibiting corrosion and the formation of rust,

it has been observed that the surfaces of metals coated with such slushing compounds are frequently badly tarnished or discolored. Although this problem of 'discolorationand tarnishing of metals coated with slushingcompounds containing soaps of preferentially oil-soluble sulfonic acids derived-from petroleum oil's has been inves tlgated for a number of years it has not been solved prior to the present invention.

It is an object of the present invention to-provide a slushing compound containing as a constituent thereof a soap of a preferentially oilsoluble sulfonic acid, derived from a petroleum oil, which will not cause tarnishing or discolora- -tion of the metal to which it is applied.

It is another object of the present invention to provide a slushing compound containing a non- .Univer'sarviscosity at 100 rived from petroleum following example: V

The} petroleum oil distillate having Saybolt F. of from about 200 seconds to'about 400 seconds is treated with from about 7to about 8 pounds of fuming sulfuric acid per gallon of oil in one-half pound increments or "dumps" After the acid sludgefrom each one-half pound acid dump is settled and withdrawn, thenext one-half pound of fuming" sulfuric acid is. added to the oil. The temperature of the oil before the fuming acid is added thereto is maintained at a temperature below about F.

oils is illustrated. by the but due to the heat of reaction upon the addition of the sulfuric acid, the temperature ofrthe oil may rise to from about F. to about F. After the required total amount of fuming sulfuric acid has been added to the oil and the oil freed of acid sludge, the acid treated oil'containing oil-soluble sulfonic acids dissolved therein,

- is neutralized with a solution of sodium hydroxide. The aqueous alkali solution is then sepafonic soap obtained in this manner contains from about 30% to about 60% sodium sulfonate, from about 30% to about 60% oil, from about 1% to about water, and up to 10% of inorganic salts which may be removed by the procedure hereinafter described;

The above-procedure may be modified after the acid sludge is removed from the acid treated oil. The oil containing dissolved sulfonic acids is extracted with about 60% alcohol to remove the sulfonic acids which may then be neutralized with sodium hydroxide and subsequently freedof the alcohol by distillation.

The crude soaps of these preferentially oilsoluble sulfonic acids obtained by the procedure described above may be freed of inorganic salts by purification. This purification is preferably accomplished by dilution of the crude soap with from about /g to about 10 parts, preferably 1 to 2 parts of 50% or higher strength alcohol, preferably alcohol of 60 to 70% strength, and allowing the salts to settle while maintaining the mixture within the temperature range of 130 to 175 F., preferably 155 to 165 F. When the salts have settled the supernatant alcohol-soap layer is separated and the alcohol is recoveredby conventional distillation procedure.

The soaps of these preferentially oil-soluble sulfonic acids obtained in the manner above described difier from other oil-soluble soaps of sulfonic acids from other fractions such as for example, those obtained by treating petroleum distillates of from about 60 seconds to about 130' seconds Saybolt Universal viscosity at 100 F. with from about 3 pounds to about 4 pounds of fuming sulfuric acid per gallonof oil, and the petroleum sulfonates obtained by treating distillates of from about 80 seconds to about 130 seconds Saybolt Universal viscosity at 100 F. with about 5 pounds of fuming sulfuric acid per gallon of oil. In addition to inhibiting the formation of tarnish and/or discoloration, which other sulfonates do not, the petroleum sulfonates of the present invention differ from other petroleum sulfonates in that the former are substantially less soluble in water than are the latter, although they do show some hydroscopic tendencies.

The effectiveness of the particular petroleum sulfonates used in the present invention in preventing discoloration and/or tarnish of metal surfaces on which it is applied is demonstrated by accelerated tests carried out in a humidity cabinet. wherein intermittent periods of heating and cooling are employed while maintaining saturated air conditions within the cabinet. The humidity cabinet which is provided with heating units and thermal regulators for automatic temperature control is maintained on a cycle of 24 hours cooling at 40-45 F. and four hours heating at 100 to 105 F. A water level of 2-3 inches is maintained in the bottom of the cabinet to give approximately saturated conditions at all times. Cold-rolled open hearth steel strips of approximately 1 x 4 inches are coated with the rust preventive material and suspended by glass hooks to a glass rod running across the top of the humidity cabinet. To insure that only moisture of condensation comes in contact with the strips, stainless steel shields are placed above the strips in such a position that no moisture from the shields could drip on the strips. The

following petroleum sulfonates were tested under the foregoing conditions:

and neutralized with'sodium hydroxide. The

sulfonate so obtained is that employed injace cordance with the present invention.

Sulfonate H" sulfonates obtained from-distil I lates of from about 60" to about 130 seconds Saybolt Universal viscosity at 100 F. bytreating with from 3 to 3 /2' pounds of fuming sulfuric acid per gallon of distillate, and neutralizing with sodium hydroxide.

Sulfonate III" sulfonates obtained from dis tillates of about seconds to about 130 seconds Saybolt Universal viscosity at F. by treating with 5 pounds of fuming sulfuric acid per gallon of distillate, and neutralizing with sodium hydroxide.

sulfonates II and III are the type of sulfonates heretofore used in slushing compounds. These were found to cause tarnish and discoloration of metal surfaces. 7

The results obtained in the humidity cabinet tests on naphtha. solutions of the foregoing type of petroleum sulfonates are shown in the follow ing table.

TABLE I Humidity cabinet tests of petroleum sodium sulfonates in naphtha solution Analysis oisodium Petroleum l Sodium sulfonate v Song -tion' -C ondition sulionate 1188 of I of strips Soap 011 Salt .nlo F Per- Per Per- Per- Per-i cent cent cent cent can't Days 1. I-.. 34.2 58.8 4.6 6.0 10: 2.

v 20 a 30 5 Dry 30 3 I II 46.9 46.2 1.8 1.6 '10 2 Sevcrerus't."

I Tarnish. 20 2 Severe rus 'Isrnish. 30 2 Severe rust Tarnish.

. Dry 30 3 Severe rust Y Ternish III .i 45.7 48.6 1.34 1.4 30 2 Tamish.

- Severe rust.

The foregoing data clearly demonstrate the tarnish forming tendencies of sodium sulfonates I! and III and theabsence of any tendency of sulfonate I to form tarnish.

Depending upon the severity of the conditions? periodic table may be employed. Thus, for example, we may employ the potassium, calcium,. barium, tin, lead, aluminum, chromium, cobalt, and nickel soaps of the sulfonic acids obtained by treating petroleum'distillates of from about 70 to about 500 seconds or higher, and preferably of from about 200 seconds'to about 400 seconds thereof.

' various viscosities bein'g Saybolt Universal viscosity at 1?. with from about 6 to about apound's, and'prererably from about 7 to about 8 pounds oiiuming sulfuric wax we may use to advantage is the refined grade acid per gallon or distillate. In'addition to the sulionate the slushing compounds employed may I v contain mineral oils, petroleum naphthas, waxes,

.petrolatumsfatty materials such ized paramn The consistency ofthe slashing compounds "em?- ployed can be varied toflsuit-the need, .oilsof sulfonate of the type hereindescribed and oils having Saybolt Universal viso'osities-o'f from-about;

V I as degras, oxidwax oresters thereoig or mixtures" u d to ;obtain composi- 'tions'. of the desired fluidity. For indoor protec 'tion we'have .found that mixesofv-th petroleu M 01' very high melting point "tacky petroleum wax having a melting point of from about 140' F. to about 150 F. or higher. We may also employ blends oi' hlsh melting point'petrolatum waxes and beeswax. As constituents we may use petrolatums of aboutllO" F. to about F. melting point and/or petrolatum base stocksot'about F. to about F. melting point or mixtures ofeach .or bothor these.

'The following table givesyin percentages by weight, the compositions slushing compounds.

tion thereto.

I iiontposition ofslushing compounds E xample Sodium Bulionate (oil free). Petrolatum-(1l8-l28iF. M-. Petrolatur n (112120 F. M. P Petrolatum base 1 (135'- F..M; P

with 78 gey olt Universal viscosity.

about 6 a crude beeswax. 60 seconds at 100 F. to about 200 seconds or more at 210 F. are effective in providing adequate protection to the metal surfaces to which they are applied. If necessary, slushing compounds of the proper visc'osity'may be obtained by mixing oils suited for protecting highly finished metal articles ploy slushing compounds which are semi-solid or -5 solid since under very severe conditions of 'ex-' posure, such as exposure to heavy rains; hot-sun's,

l Obtained by treating distillates of from about seconds to about 400 seconds Saybolt Universal viscosity at 100 F uuds of turning sulfuric acid,and neutralizing with sodium hydroxid lace oi the mineral wax we can'employ a blend of about 2% petrolatum wax of about of-high viscosity with oils of low viscosity. Light liquid slushing compounds are particularly well F. melting point and The compositions of the slushing compounds -are solid at room temperatures are usually melted to facilitate application, the melted product being applied either by'dipping. swabbing, or by spraying..' To facilitate the application of the solid slushin-g' compounds without heating. the same may be thinned with a solvent, preferably a pedirt and dust liquid slushing compounds-are notas eflective as the semi-solid or solid compositions. When slushing oils are used under these severe conditions they may be washed ofijby' rain,- leaving the surface exposed to rusting. Exposure to the hot sun, tends to evaporate themore vola tile slushing oils containing a. relativelyvolatile diluent such as petroleum naphthas as the dim ent, and dirt and dust'fa'lling upon the s'urfaoe's tect-ive film For these reasons the use of semisolid or solid slushing compound sa're to be'pr'eferred to theli'quid compositions-for. protection under severev conditions.

, su t me ons-er semisolidslushingcompounds may beprepa'red with waxessuch asparamn wax,

of-about'300? F. and a maximum distillation temperature of about 430? F. The inspections of typical 'petroleum-naphthaswe may employ are' s, r w I Naphtha Naphtha A s 1 .lnitialboiling 'pointlull-fl Jr" 307 302 Maximum boiling point F 400 418 t distillation point... F. 33?. s42

FIasi1 F'. 102 103 ill) absorb t e oil and make it ineffective'as a protroleum naphtha having an initial boiling point Petroleum solvents falling within the above speci- 1 -fications :are ol'eum spirits and Stanisol.

While we have described our invention in connectionwith certain specific embodiments thereillustration only and not'by way of it is to be understood that these are by way of 4 no described maybemodified without depart by thesappended claims.- I We claim:- o P '1. A slushing composition containing small soap of preferentially oil-soluble sulfonic acids. obtained by treating a petroleum distillate having i'r'igjfrorn the-scope of our inventiongas d'enned o of limitation." It is to be understood that aparticularcomposia Saybolt Universai viscosity at 100 F. above about 70 seconds with-about 6 pounds to about 9 pounds of concentrated sulfuric acid per gallon of distillate.

2. A slushing composition as described in claim about 70 seconds to about 500 seconds with about- 6 pounds to about 9 pounds of concentrated sul-- furic acid per gallon of distillate.

4. A slushing composition as described in claim 3 in which the metal soap is sodium soap.

5. A slushing composition asv described in claim 3 in which the metal soap is a calcium soap.

6. A slushing composition as described in claim 3 in which the metal soap is an aluminum soap.

'7. A slushing composition as described in claim 3 containing from about. 1% to about 40% of. the meta1 soap f the preferentially oil-soluble sul-' fonic acids.

8. A slushing composition containing a metal soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about 7 pounds to about 8 pounds of fuming sulfuric acid per gallon of distillate.

9. A slushing composition as described in claim to about 8 pounds of fuming sulfuric acid per gallon of distillate.

13. A slushing composition containing a mineral oil and from about 1% to about 40% of a meta1 soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about '7 to about 8 pounds offuming sul furic acid per gallon of distillate."

'14. A slushing composition containing mineral oil, wax and a metal soap or preferentially oilsoluble sulfonlc acids obtained by treating a pctroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about 'I to about 8 pounds of fuming sulfuric acid per gallon of distillate.

15. A slushing composition containing mineral oil, a fatty material and a metal soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about 7 to about 8 pounds of fuming sulfuric acid per gallon of distillate.

16. A slushing composition as described in claim 15 in which the fatty material is degras.

lfl. A slushing composition containing a mineral oil, oxidized paraffin wax and a metal soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about 7 to about 8 pounds of fuming sulfuric acid per gallon of distillate.

18. A slushing composition containing mineral oil, wax, a metal soap of preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having .a Saybolt Universal viscosity at 100 F. of from about 200 seconds-to about 400 seconds with from, about 7 pounds to about 8 pounds of fuming sulfuric acid per gallon of distillate and a suflicient amount of a petroleum solvent to render the composition fluid at ordinary room temperatures.

19. A slushing composition as described in claim 18 in which the petroleum solvent is a petroleum naphtha having an initial boiling point of about 300 F. and a maximum boiling point of about 430 F.

20. A slushing composition containing mineral oil, petrolatum wax, beeswax and a metal soap cf preferentially oil-soluble sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about 200 seconds to about 400 seconds with about 7 to about 8 pounds of fuming sulfuric acid per gallon of distillate.

" 21. A slushing composition containing a metal soap of preferentially oil-soluble purified sulfonic acids obtained by treating a petroleum distillate having a Saybolt Universal viscosity at 100 F. of from about seconds to about 500 seconds with about 6 pounds to about 9 pounds of concentrated sulfuric acid per gallon of distillate. ELMER WADE ADAMS. GEORGE W. FLINT.