US2419584A

US2419584A - Mineral oil composition

Info

Publication number: US2419584A
Application number: US573466A
Authority: US
Inventors: Thomas T Noland
Original assignee: Socony Vacuum Oil Co Inc
Current assignee: ExxonMobil Oil Corp
Priority date: 1945-01-18
Filing date: 1945-01-18
Publication date: 1947-04-29
Anticipated expiration: 1964-04-29

Description

Patented Apr. 29, 1947 MINERAL OIL COMPOSITION Thomas '1. Noland, Richmond, Ky., assignor to Soeony-Vacuum Oil Company, Incorporated, a corporation of New York No Drawing. Application January 18, 1945, Serial No. 573,466

12 Claims.

This invention has to do with the stabilization of viscous mineral oil fractions against the deleterious effects of oxidation or deterioration with use by the addition thereto of oxidationinhibitors. More specifically, the invention is directed to the improvement of viscous mineral oil fractions by a combination of such inhibitors; namely, a primary oxidation inhibitor and a secondary inhibitor which when admixed with a viscous mineral oil in minor proportions will prevent or delay certain other undesirable changes taking place in the oil.

As is well known to those familiar with the art, substantially all of the numerous fractions obtained from mineral oils and refined for their various uses are susceptible to oxidation. The susceptibility of an oil fraction to oxidation and the manner in which such oxidation manifests itself within the oil varies with the type and degree of refinement to which the oil has been subjected and with the conditions under which it is used or tested; that is, the products formed in an oil fraction as a result of oxidation and the degree to which they are formed depends upon the extent to which the various unstable constituents or constituentswhich may act as oxidation catalysts have been removed by refining operations and also upon the conditions of use to which the oil is put.

The present invention is predicated upon the discovery that the oxidation characteristics of viscous mineral oil fractions are greatly improved by the incorporation therein or minor proportions of each of two inhibitors which are designated herein as primary oxidation inhibitors and secondary inhibitors.

The primary oxidation inhibitors contemplated herein are stable, oil-soluble phosphorusand sulfur-containing reaction products obtained by reaction of phosphorus penta-sulilde and a cycle stock characterized by an olefin and an aromatic content of from about 3 per cent to about '7 per cent and from about 40 per cent to about 60 per cent, respectively, under the following interrelated reaction conditions:

1. Between about 1 per cent and about 8 per cent by weight of P285 based upon the weight of said cycle stock,

2. A temperature between about 125 C, and about 200 C., and

3. A relatively short reaction time.

The hydrocarbon reactants are, as indicated above, cycle stocks containing from about 3 per cent to about 7 per cent of olefins and from about 40 per cent to about per cent of aromatics, as determined by the following test method:

Twenty-five milliliters of a solution containing per cent by weight of sulfuric acid (sp. gr.. 1.84) and 30 per cent of P201; are placed in a glass stoppered sulfonation bottle (a modified Babcock bottle-A. S. I'. M. Standards on Petroleum Products and Lubricants, Sept. 1943, page 381). The bottle is immersed in ice water for five minutes; then 10 milliliters of the hydrocarbon are added. The bottle is shaken for 10 minutes while cooling with ice water. Sulfuric acid (sp. gr., 1.84) is added until the top meniscus of the hydrocarbon layer is brought up to the 100 per cent mark on the graduated portion of the neck. The bottle is then stoppered and is centrifuged for 10 minutes. The milliliters of hydrocarbon oil layer remaining are read and this value is subtracted from the original 10 milliliters to obtain the combined amounts of arcmatic and olefin contents of the sample. By repeating the same procedure, except for using per cent sulfuric acid instead of the H:SO4P:O mixture, the olefinic content of the sample is obtained. Thus olefinic content subtracted from the combined olefin and aromatic content gives the amount of aromatic material present.

Preferably, the hydrocarbon reactants are also characterized by the following: boiling range from about C. to about 400 0., and specific gravity from about 0.88 to about 0.93. In general, such cycle stocks are obtained from thermal cracking operations of crude oils, but other stocks characterized as above may also be used. Typical of such other stocks are light gas oils, such as a light gas oil containing 4 per cent oleflns and 46 per cent aromatics, a specific gravity of 0.8833 and a boiling range from C. to 380 C. For this reason, the hydrocarbon reactants may be broadly considered as hydrocarbon stocks characterized by the aforesaid percentages of olefins and aromatics.

The amount of P285 reacted with the cycle stocks contemplated herein is an important consideration. Stable, oil-soluble reaction products containing appreciable quantities of phosphorus and sulfur are obtained when the amount of P255 so reacted is from about 1 per cent to about 8 per cent by weight of the hydrocarbon reactant. Particularly preferred reaction products, however, are obtained with about 5 per cent by weight of P285. When amounts of the order of 10 per cent and 15 per cent of P285 are used, it has been found that the phosphorusand sulfur-containing reaction products obtained therewith are unstable when heated and are oil-insoluble. As used herein the term "011 soluble" is descriptive of those reaction products which are soluble in oil in amounts of at least 1 per cent by weight.

Another important consideration in the prepuct--product B-contained 1.26 per cent phosphorus and 3.6 per cent sulfur.

EXAMPLE 3 Five hundred grams of product B obtained in aration of the aforesaid reaction products is reac- 5 Example 2 were vacuum dlstmied to a maximum tion time. In general, superior reaction products. temperature of 172? 3 Order to remove in quantities Such as shown in the following unreacted recycle stock therefrom. The residueamples. are obtained when the reaction time is product ccontamed per cent Phosphorus relatively short. such as from about 2 hours to and per cent 511mm about 8 hours. While reaction times as long as Reaction product? obtamed from recycle stock about 12 hours have been used and satisfactory and Prepared as P Example 2 above are shown reaction products obtained therewith. reaction Table I below m order to demntrate the times in the neighborhood of 4 hours are influence of each of the several react1on variaferred. It is to be understood, however, that the 15 mes-um?" temperature and concentration of reaction time may be varied considerably depend- P255 The copper Strip tests referred to m the ing upon the quantities of reactants and the rem were made by immersing a P0115119: copper action temperatures used in the preparation of F in a 1 cent blend of a roeactmn product said reaction products in 011 and heating the blend at 100 C. for 24 hours. The interrelation of the foregoing reaction The copper F .F the plesence or absence of free 01 active sulfur which corrodes factors willbc apparent from the following typical copper An asterisk H has been used in the examples recited below, and also those set forth table wherever the copper strip used in the copper m Table strip test was not corroded in each test; that the EXAMPLE 1 5 reaction product was stable; and that the reaction A reaction stock-recycle stock A-from a ther- 2 product was soluble in oil.

Table I P cent Composition p" ,up Product (by at) i?" 5g lg Percent s a Stability Solubility E. s 100-200 4 1.23 as F 5 4 Unstable. Insoluble.

:22 .2 ii I I I Conceal 1 I I mal liquid phase cracking operation and having It will bqapparent from the data tabulated in the following characteristics, was used: 45 TableI above that reaction temperatures in excess of 200 C, are unsatisfactory. The desired reac- 212? .321252:;5::jjjlf ji iSET: tion products as indicated in Table I are those Specific gravity 03939 prepared under the reaction conditions defined Aniline number 105.5 heremabove' Boiling range (0); Another cycle stock which was also found to Initial 3 Pt 97 be particularly desirable was a cycle stock. obm cent 230 tained from a Cross still, and characterized by 50 do 274 the following: do- 32'? Olefin content per cent 5 End point 366 Aromatic content do- 57 Recovery per cent.-- 98.5 Specific gravity 0.9236 Aniline number 80 One thousand grams of recycle stock A was reacted, with stirring, with '70 grams or P235 at Bomng range -370 180 C. for 8 hours. The reaction mixture thus While products A, B and C, shown above in obtained was diluted with naphtha 1 boiling range (30 E a p s 1 through and Products E, G, H 88-135" C.) washed with 20 per cent Nags soluand I shown in Table I are particularly desirable tion. water washed, filtered and the fill rate heated for use in petroleum f a t r a ed 113 11 to c. at 10 mm. pre sure to remove the p s p p ed nasimi r m nn r f om o h r naphtha. The reaction product contained 1.19 hydrocarbon reactants are undesirable or such per cent phosphorus and 3.06 per cent sulfur, and 05 use. The data pres nted i Table II b low is illusis identified hereinafter s product A, trative of their undesirable character. The cop- EXAMPLE 2 per strip tests referred to in this table were obtained in the manner described in connection ne th u and r m of r cycle l A w with Table I. The heat stability tests shown in ac with stirring. with 50 grams of 5 at 70 Table II were made by heating a 1 per cent blend for 3 hours" The 1(faction mixture 50 of a reaction product in oil at 100 C. for 24 hours. obtained was then co led to 100 C.. 52.5 grams An asterisk has been used as in Table I to indi- (5 per cent by weiclitl of Aiiapuleus clay \vas cote that the copper strip in the copper strip added thereto and the clay was subsequently rctests was not corroded in each test, and that the moved thereirom by filtering. The r action prod- 76 f ti n product was stable to heat.

Table II Composi- P t tion Prod- Temp. Temp. Co per Strip Heat Hydmcarbo" uct g fl Q o. hours Per wst Stability Rema'ks cent cent P S Catelytically Cracked Cycle M 190-195 434 0.88 2.1 Corrosive black Poor: sludge Sludge formed durin Stock: strip deposited reaction: additions Per cent Olefin, 3 oil-insoluble sludge Per cent Aromatic, 35 generated on standg. castalyically Cracked Cycle N 5 190-195 4% 1.04 2.0 do do Do.

toc

Percent Olefin, 1 Per cent Aromatic, 35 No. 2 Fuel Oil from Catalytic O 5 80-200 2% do Unstable Do.

CrackingO ration:

Per amt lefln,0 Per cent Aromatic, 36 i It will be apparent from the results set foith in Table II above that the reaction products of hydrocarbon reactants which are not characterized by the required olefin and aromatic contents defined above are greatly inferior to the related reaction products from the cycle stocks contemplated herein and illustrated in Examples 1 through 3 and in Table I. For example, it is apparent that the reaction products obtained from the catalytic cycle stocks and the No. 2 fuel oil defined in Table II are corrosive to copper and are unstable when heated, being so unstable when heated that considerable quantities of oil insoluble sludge are deposited therefrom. Thus, the latter reaction products have little or no value as addition agents for petroleum fractions, particularly viscous mineral oils. On the contrary, however, the reaction products contemplated herein are not corrosive to copper and are stable when heated. It will be recognized, therefore, that the reaction products of this invention are much more marketable in the oil industry and other industries than are the related reaction products of such hydrocarbon reactants as those shown above in Tabl II.

When used in viscous mineral oil fractions in small amounts, the aforesaid primary oxidation inhibitors effect improvement of several of the oxidation characteristics thereof by preventing, for example, corrosion of hard metal bearings, by inhibition or acid-formation, by inhibition of formation of gummy deposits in engines, by preventing increase in viscosity, etc. However on standing for several days or when heated and then left to stand, an oil composition comprised only of a viscous mineral oil fraction and a primary oxidation inhibitor tends to become cloudy. This shortcoming has now been overcome by incorporating in such oil composition a small amount of a secondary inhibitor.

The secondary inhibitors of this invention which are capable of regulating or preventing the aforesaid haze problem are oil-miscible metal salts of sulfonic acids. These sulfonic acids include both those prepared from aromatic hydrocarbons. or substituted aromatic hydrocarbons, by treatment with strong sulfuric acid, olcum. chlorsulfonic acid, etc., and those obtained by treatment of variou petroleum fractions with the same reagents. Any metallic salt of any organic sulfonic acid that is sufficiently soluble in petroleum oils is contemplated by this invention as the secondary inhibitor. Among the metals which are especially suitable for this purpose are sodium, potassium, magnesium. calcium, cobalt, tin, strontium and barium. Particularly preferred are barium, sodium and calcium.

Of the sulfonic acids contemplated by the present invention, preference is given to the substituted aroma-tic sulfonic acids and to the petroleum sulfonic acids. Both monoand polysubstituted aromatic sulfonic acids are contemplated, particular prcference being given to the alkyl-substituted benzene sulfonic acids. 01 the monoand poly-alkyl substituents for the aromatic sulfonic acids, the so-called "wax" substituents-that is, those alkyl substituents containing at least about 20 carbon atoms-are particularly preferred.

The praticularly-preferred compositions of primary and secondary inhibitors in viscous mineral oil fractions which are contemplated herein are those in which the primary inhibitor is 9. P255- cycle stock reaction product or a Pass-light gas oil reaction product, of the type described above, and the secondary inhibitor is either barium or calcium diwax benzene sulfonate, barium or calcium petroleum sulfonate, or sodium petroleum sulfonate.

As, stated above, oil compositions comprising only a viscous mineral oil fraction and a typical primary oxidation inhibitor have a tendency to develop a haze, the formation of which can be suppressed by the addition to such compositions of a small amount of a secondary inhibitor. namely, an oil-miscible metal salt of a sulfonic acid. This fact is demonstrated by the test results set forth in table III below. The oil used in these tests was a solvent-refined S. A. E. 10 grade motor oil.

The Pass-cycle stock reaction product (prodnot B) was prepared as described in Example 2 above.

The barium diwax benzene sulfonate used as the haze-inhibitor was" prepared by reacting a 10 per cent chlor-paraffin wax with benzene to form a diwax benzene, which was treated with oleum to form the sulfonic acid, which in turn was neutralized with barium hydroxide. In order to reduce the viscosity and to increase the ease of handling, this product was blended in a 1:1 ratio with an S. A. E, 30 grade motor oil. The blend contained 5.17 per cent barium and 1.5 per cent sulfur.

The sodium petroleum sulfonate used in these tests was the sodium salt of an oil-soluble sulionic acid prepared by treating a Mid-Continent, distillate of seconds Saybolt Universal viscosity at F. with olcum. It contained 2.57 per cent sulfur.

The barium petroleum sulfonate was prepared from the above sodium salt by treatment with Each solution. It contained 6.9 per cent barium.

The variou blends indicated in Table III were placed in -ounce bottles and kept at room temperature in diffused light for the length or time given below, with the following results:

8 and sulfur-containing reby reaction of phossoluble, phosphorusaction product obtained The results shown above in Table III demonstrate effectively that haze-formation in an oil containing as a primary oxidation inhibitor a PzSs-cycle stock reaction product is appreciably inhibited by the addition of a small amount of the secondary inhibitor contemplated by this invention.

The amount of secondary inhibitor necessary to effect the desired haze-inhibition depends upon the concentration of primary oxidation inhibitor in the oil as well as upon the type of mineral oil fraction used. In general, however, from about 1.0 to about 10.0 per cent by weight of the secondary inhibitor based upon the amount of primary inhibitor present will be suilicient to effectively regulate haze-formation. The amount of primary oxidation inhibitor contemplated for use in the oil compositions of the present invention is from about 0.1 per cent to about 3.0 per cent, although about 0.1 per cent to about 1 per cent of these reaction products will usually suflice. Accordingly, the amount of secondary inhibitor used in the oil blend will be from about 0.001 per cent to about 0.3 per cent by weight.

As contemplated herein, the primary and secondary inhibitors or this invention may be incorporated in a viscous mineral oil traction either by adding the secondary inhibitor to the primary inhibitor before both are blended with the oil or by adding the secondary inhibitor separately to the blend of the oil and theprimary inhibitor. The term, "mineral oil composition, as used herein and as recited in all of the appended claims, is inclusive of all mineral oil fractions containing a primary oxidation inhibitor and a secondary inhibitor and of all oil compositions obtained or prepared by any of the proced ures hereinabove described. Any oil compositions so obtained or prepared is substantially free of haze normally occurring in an oil composition containing the primary oxidation inhibitor alone.

It is also to be understood that the examples, procedures, and oil compositions described herein are illustrative only and are not to be construed as limiting the scope of this invention thereto. Thus, all cycle stocks and light gas oils as defined above may be used in place of those shown in the foregoin examples; any metallic salt of any sulfonic acid that is sufliciently soluble in petroleum oils is suitable for use as the secondary inhibitor; and the mineral oils disclosed above are but typical of all viscous mineral oil fractions which may be used in this invention.

I claim:

1. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating effects of oxidation upon the oil, of a stable, oilphorus penta-sulflde and a hydrocarbon stock at a temperature between about C. and about 200 C. for a relatively short reaction time. said hydrocarbon stock being characterized by an olefin content of from about 3 per cent to about 7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said hydrocarbon stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze. of an oil-miscible metal salt of a sulfonic acid. I

2. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating effects of oxidation upon the oil. of a stable, oilsoluble, phosphorusand sulfurcontaining reaction product obtained by reaction of phosphorus penta-sulfide and a light gas oil at a temperature between about 125 C. and about" 200 C. 0: a relatively short reaction time, said light gas oil being characterized by an olefin content of about 4 per cent and an aromatic content of about 46 per cent, said phosphorus penta-sulflde representing about 5 per cent by weight of Said light gas oil. and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suiliclent to suppress the formation of said haze, of an oil-miscible metal salt of a sulfonic acid.

3. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, suflicient to inhibit the deteriorating effects of oxidation upon the oil, of a stable, oilsoluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus penta-sulfide and a cycle stock at a temperature between about 125 C. and about 200 C. for a relatively short reaction time. said cycle stock being characterized by an olefin content of from about 3 per cent to about 7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said cycle stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent. suflicient to suppress the formation of said haze. of an oil-miscible metal salt of a sulionic acid.

4. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating effects of oxidation upon the oil. or a stable. oilsoluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus penta-sulflde and a cycle stock at a temperature between about 125 C. and about 200 C. for a reaction time from about 2 hours to about 8 hours, said cycle stock being characterized by an olefin content of from about 3 per cent to about '1 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said cycle stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze, of an oil-miscible metal salt of a sulfonic acid.

5. A mineral oil composition comprising a. viscous mineral oil fraction containing a minor proportion, i'rom about 0.1 per cent to about 3.0 per cent, sufllclent to inhibit the deteriorating efiects of oxidation upon the oil, of a stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus pentasulfide and a cycle stock at about 150 C. for about 8 hours, said cycle stock being characterized by an olefin content 01. about 6 per cent and an arcmatic content of about 4'. per cent, said phosphorus penta-sulfide representing about 5 per cent by weight of the said cycle stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, sufiicient to suppress the formation of said haze, of an oil-miscible metal salt oia sulfonic acid.

6. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating effects of oxidation upon the oil, of a stable, oil-soluble phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus pentasulflde and a hydrocarbon stock at a temperature between about 125 C. and about 200 C. for a relatively short reaction time, said hydrocarbon stock bein characterized by an olefinic content or from about 3 per cent to about '7 per cent and an aromatic content of from about per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said hydrocarbon stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze, of an oil-miscible metal salt of an alkylsubstituted aromatic sulionic acid.

'7. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating effects of oxidation upon the oil, of a stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus pentasulfide and a hydrocarbon stock at a temperature between about 125 C. and about 200 C. for a relatively short reaction time, said hydrocarbon stock being characterized by an olefin content of from about 3 per cent to about 7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said hydrocarbon stock, and the said reaction product normally tending 10 to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, sufficient to suppress the formation of said haze, of an oil-miscible metal salt oi an alkylsubstituted benzene sulfonic acid.

8. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, irom about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating eflects of oxidation upon the oil, of a stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus pentasulfide and a hydrocarbon stock at a temperature between about C. and about 200 C. for a relatively short reaction time, said hydrocarbon being characterized by an olefin content oi. from about 3 per cent to about 7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said hydrocarbon stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, sumcient to suppress the formation of said haze, of an oil-miscible metal salt of a wax-substiuted benzene sulfonic acid.

9. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufficient to inhibit the deteriorating eflects of oxidation upon the oil, of a; stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus pentasulfide and a hydrocarbon stock at a temperature between about 125 C. and about 200 C. for a relatively short reaction time, said hydrocarbon stock being characterized by an olefin content of from about 3 per cent to about 7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus pentasulfide representing from about 1 per cent to about 8 per cent by weight or the said hydrocarbon stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze, of an oil-miscible barium salt of diwax-substituted benzene sulfonic acid.

10. A mineral oil composition comprising a, viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, suificient to inhibit the deteriorating effects of oxidation upon the oil, of a stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus-pentasulfide and a hydrocarbon stock at a temperature between about 125 C. and about 200 C. for a relatively short reaction time, said hydrocarbon stock being characterized by an olefin content of from about 3 per cent to about '7 per cent and an aromatic content of from about 40 per cent to about 60 per cent, said phosphorus penta-sulfide representing from about 1 per cent to about 8 per cent by weight of the said hydrocarbon stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suificient to suppress the formation of said haze, of an oil-miscible metal salt of a petroleum sulfonic acid.

11. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, SLlffiCiBIiC to inhibit the deteriorating effects 1 l of oxidation upon the the oil, of a stable, oilsoluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus penta-sulflde and a cycle stock at about 150 C. for about 8 hours, said cycle stock being characterizeci by an olefin content of about 6 per cent and an aromatic content of about 47 per cent, said phosphorus penta-sulflde representing about 5 per cent by weight of the said cycle stock, and the said reaction product normally tending to torm a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze, of an oil-miscible barium salt of diwax-substituted benzene sulfonic acid.

12. A mineral oil composition comprising a viscous mineral oil fraction containing a minor proportion, from about 0.1 per cent to about 3.0 per cent, sufllcient to inhibit the deteriorating efl'ects of oxidation upon the oil, of a stable, oil-soluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus penta-sulflde and a cycle stock at about 150 C. for about 8 hours, said cycle stock being characterized by an olefin content of about 6 per cent and an aromatic content of about 47 per cent, said phosphorus penta-sultide representing about 5 per cent by weight or the said cycle stock, and the said reaction product normally tending to form a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, sufilcient to suppress the formation of said haze, of an oil-miscible sodium salt of a petroleum sulf onic acid.

THOMAS T. NOLAND.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,136,391 Miller Nov. 15, 1938 2,202,394 Morway May 28, 1940 2,279,086 Bergstrom Apr. 7, 1942 2,315,529 Kelso Apr. 6, 1943 2,316,082 Loane Apr. 6, 1943 2,342,572 Cook Feb. 22, 1944 2,365,209 Musselman Dec. 19, 1944 2,373,094 Berger Apr. 10, 1945 Certificate of Correction Patent No. 2,419,584.

April 29, 1947.

THOMAS T. NOLAND It is hereby certified that error appears in the printed s numbered patent requiring correction as follows: Column 6,

test strike out the last do; and that the said Letters Patent ing Copper Strip ecification of the above able II, under the headshould be read with this correction therein that the same may conform to the record of the case in the Patent Oifice.

Signed and sealed this 29th day of July, A. D. 1947.

LESLIE FRAZER,

First Assistant Oommiambner of Patents.

1 l of oxidation upon the the oil, of a stable, oilsoluble, phosphorusand sulfur-containing reaction product obtained by reaction of phosphorus penta-sulflde and a cycle stock at about 150 C. for about 8 hours, said cycle stock being characterizeci by an olefin content of about 6 per cent and an aromatic content of about 47 per cent, said phosphorus penta-sulflde representing about 5 per cent by weight of the said cycle stock, and the said reaction product normally tending to torm a haze in the oil; and a minor proportion, from about 0.001 per cent to about 0.3 per cent, suflicient to suppress the formation of said haze, of an oil-miscible barium salt of diwax-substituted benzene sulfonic acid.

THOMAS T. NOLAND.

April 29, 1947.

Signed and sealed this 29th day of July, A. D. 1947.

LESLIE FRAZER,

First Assistant Oommiambner of Patents.