US2322307A - Compounded oil - Google Patents

Description

Patented June 22, 1943 2,322,301 COMPOUNDED om George L. Neely and Frank W. Kavanagh, Berkeley, Calif., assignors to Standard Oil Company of California, San Francisco, Calii'., a corporation of Delaware No Drawing. Application .lune 20, 1939,

Serial No. 280,124

11 Claims. The invention relates to compounded lubricating oils, and especially involves the provision of improved lubricating oils for internal combustion engines which will inhibit piston ring sticking and which will posses other advantae geous properties not obtainablewith prior known single compounding agents. invention provides lubricants having not only the ability to inhibit piston ring sticking but characterized by reduced corrosivity toward bearing metals, reduced jelling tendencies where jelling may not be desired, and enhanced lubrication values as indicated by factors such a improved ability. to prevent scoring and uneven or undue wear of pistons, piston rings or cylinder walls of engines, and also as determined by ability to wet or adhere to hot metal surfaces, by lower wear, by lower friction and higher film strength, and by enhanced protection to bearings under high loads. tion also permit production of compounded lubricants and compoundin agents therefor having improved stability as respects resistance to oxidation, to high temperatures, to storage atlow temperatures, and to storage in the presence of water.

- The desirability of preventing the formation of adhesive oxidation products in hydrocarbons at elevated temperatures such as 425 to 525 F. has been recognized. In general, however, oxidation inhibitors which are operative at lower temperatures to inhibit the formation of such materials are not operat ve at extremely high tempera tures, such as 500 F. Because of the inherent instability of hydrocarbons in the presence of an oxidizing agent under such extreme condi' tions of temperature, the possibility of finding a satisfactory oxidation inhib tor has not been promising, and there appears to be no known law of chemical nature which would enable one to predict or select from the vast list of chemical compounds those which would be operative at temperatures above 425 F. A large number of known oxidation inhibitors have been tried under these severe conditions and found to be unsatisfactory or totally inoperative.

When hydrocarbon compounds such as those occurring in mineral oils of the lubricating boil-. ing range are heated to temperatures of from approximately 425 to 525 F. in the presence of an oxidizing agent such as an oxygen-containing gas, these compounds are partially oxidized and tend to deposit an adhesive gum or resinous material on surfaces with which they are in con- I tact. Analysis of such deposits indicates that The principles of this inven- Additionally, the

the adhesive constituents comprise oxy or hydroxy organic acids'and resinous complexes of these acids, which complexes are of unknown constitution and are apparently produced by further oxidation of the acids and/or by condensation as through inter-esteriflcation oi. the hydroxy groups present/therein.

It has been discovered that incorporation of certain metal salts of difierent organic acids in the hydrocarbon mixture will inhibit formation of an adhesive deposit on metal surfaces at elevated temperatures, although such salts may not prevent or inhibit partial oxidation and decomposition of the hydrocarbons. The formation of adhesive deposits is prevented by the metal salts altering the courseof the oxy acid resinification reaction. f

It is often found that salts in which the acid components consist entirely of one acid are not satisfactory compounding agents for lubricating oils, or at least do not possess other properties which are desirable or necessary in liquid lubricating compositions. These deficiencies may arise from unsatisfactory wear rate, instability of either the compounding agent or the compounded oil, or both, at high temperatures, instability of the oil solution of the compounding agent in storage or in the presence of water,

undue corrosivity of the compounded oil toward bearing metals such as cadmium-silver or copper-lead alloys, unsatisfactory solubility of the compounding agent in the oil at low temperatures as indicated by cloud formation or jelling, undue foaming, unsatisfactory adhesion of the compounded oil to hot metal surfaces, and undesirably high friction or low film strength.

The present invention avoids at least part of the above diiiiculties by incorporating in the lubricating oil mixed organic salts of certain metals, said mixed salts containing different types of organic acids.

- In producing the lubricating compositions of thisv invention, salts of metals selected from the group consisting of aluminum, calcium, barium, strontium, zinc, magnesium, cobalt, cadmium, manganese, tin and chromium may be utilized.

Suitable mixtures and/or complex salts may be prepared by precipitation from aqueous solution. Thus one method comprises preparing an-aqueous solution containing alkali metal salts of the mixture of acids in question, e. g. sodium naph thenate and sodium stearate, in substantially equal quantities, and then precipitating the polyvalent metal salts of these acids by adding a solution containing the appropriate metal ion,

e. g. an aqueous solution oi aluminum sulfate. Such precipitation processes are preferably carried out in the presence of an organic solvent to take up the oil-soluble organic salt as it is formed. A suitable solvent comprises lubricating oil. It is to be understood that the invention, in its broader aspect, is not limited to salts prepared by simultaneous precipitation or by any other specific method.

To illustrate results which may be obtained by utilizing metal salts containing difierent types of organic acids, the following specific examples of lubrication problems involved and difllculties overcome are given:

Incorporation of both aluminum naphthenates and aluminum salts of long chain fatty-acids in lubricating oils gives improvements in lubricants which are not attainable with either salt alone. For example, 1% aluminum stearate, when dissolved in a mineral oil lubricant, causes the formation of a jell and tends to separate from the oil at low temperatures. Such a lubricant is unsatisfactory for use in internal combustion engines. By contrast, addition of 0.5% aluminum naphthenate and 0.5% aluminum stearate (total aluminum salt content is still 1%) gives a liquid non-jelling lubricant, and the tendency of the aluminum stearate to precipitate out of the oil solution at low temperatures is avoided.

Furthermore, the lubricant containing aluminum naphthenate and aluminum stearate in combination not only possesses the ability to withstand severe high temperatures without depositing gum and carbon around the piston rings of an internal combustion engine but also gives superior protection to the Babbitt bearings of such engines. The following engine tests will illustrate this property of the oil.

Reduced area bearing tests It is to be noted that the above test is an extremely severe one and involves bearing loads-not encountered in service. This test accentuates the ability of the lubricant to protect bearings under extreme conditions.

A second test illustrates performance of the same oil in protecting full size bearings in a 4- cylinder RD-4." Caterpillar Diesel engine operating under severe conditions of full load and speed. The conditions of the test were: load, 75 lbs. B. M. E. P.; speed, 1400 R. P. M.; jacket temperature, 75 F.; oil temperature, 185 F; In this test there was no failure of any bearings after 541 hrs. of operation, whereas with a lubricant containing 1% aluminum dinaphthenate and 0.25% stearic acid failure of a bearing occasion- 7 ally occurs under the severe conditions of the test after 200 hrs. operation.

Tests in which a single cylinder gasoline engine was operated under severe conditions designed to accelerate piston ring sticking show that an oil containing aluminum naphthenate and a uminum stearate will inhibit piston ring sticking under such conditions for 120 hrs. or more of engine operation, whereas the same lubricating oil without the addition of the aluminum salts will permit piston ring sticking in 30m 40 hrs.

The oil containing both aluminum dinaphthenate and aluminum stearate gives improved rates of wear over that obtained by the use of aluminum dinaphthenate alone. A- laboratory wear-testing machine comprising a V inch steel ball pressed against a 1% inch steel cylinder with a force of 40 lbs. and having the cylinder dipping in the oil to be tested and rotated at 600 R. P. M. for 16 hrs. was used to compare relative wear rates. Assuming the rate of wear to be 100% on this machine with an oil containing 1% aluminum dinaphthenate alone, an oil containing 5% aluminum stearate plus aluminum dinaphthenate gives only 30% as much wear as the oil containing only aluminum naphthenate. This represents a reduction of 70% obtained by the use of the combination of salts of aluminum.

For purposes of illustration and to enable preparation of a lubricating 011 according to the principles of thisinvention without unnecessary experimentation, the following example is given:

A basic aluminum naphthenate containing two equivalent weights of naphthenic acid to three equivalent weights of aluminum is obtained by any of the well known methods. Naphthenic acids are generally prepared by extracting the naturally occurring naphthenic acids from crude petroleum oils or other distillates containing them, usually by washing the said oils with dilute aqueous caustic soda solution whereby Water-soluble alkali naphthenates are formed. The alkali naphthenate solution may then be extracted with organic solvents to remove the major proportion of inert mineral oil contained therein. naphthenate may then be prepared by adding to a substantially neutral aqueous sodium naphthenate solution a caustic alkali and a Watersoluble aluminum salt in proportions of one equivalent weight of hydroxide 0H) per three equivalent weights of aluminum. The waterinsoluble basic aluminum naphthenate will be precipitated and the sodium salts will remain in solution. A mineral oil concentrate is prepared by dissolving ten parts by weight of the naphthenate in ninety parts by weight of the mineral oil. This concentrate is added to a mineral lubricating oil such as an S. A. E. 30 acid refined naphthenic lubricating oil stock, in quantities sufiicient to give 1% by weight of naphthenate based on the completed oil. This oil is then heated for about thirty minutes at a temperature of 250 F. by indirect heat. If superheated open steam is used for this heating operation a shorter time will generally sufiice.

An equal portion of oil base is compounded with aluminum stearate by dissolving the stearate in oil in quantities suflicient to give a solution containing 1%- aluminum stearate by The basic aluminum.

I portions at a temperature above 150' F. The

aluminum stearate compounded portion preferably should not be allowed to cool after it has v been prepared before mixing with the portion proportions in water and adding aluminum sulfate thereto until precipitation ceases. The following data are illustrative:

Stability in Oil tested storage at Wear at 32 F.

S. A. E. acid refined naphthenic oil Stable-u". 0.36. S. A. E. 30 acid refined naphthenic oil plus do... 1.40.

1% aluminum dinaphthenate. S. A. E. 30 acid refined naphthenic oil plus Separates Foams and 1% aluminum stearate. scufis. S. A. E. 30 acid refined naphthenic oil plus Stable..." 0.70.

0.5% aluminum dimphtbeuate. S. A. E. 30 acid re'ined naphthenic oil plus Separates Foams and 0.5% aluminum ste' rato. scufls. S. A. E. 30 acid refined naphthenie oil plus Stable. 0.40.

0.5% aluminum dinaphthenate plus 0.5% aluminum stearate.

The procedure for determining the above data on wear is the same as previously described.

The above tests show that an oil containing aluminum stearate alone foam and scuffs in aluminum salt 1%) is 57% and 30% of the'wear rate for the oils containing respectively 0.5% and 1% of aluminum dinaphthenatealonex V The relative proportions of naphthenate to stearate either in the complex or mixed salts may vary rather widely, depending upon the characteristics desired and the conditions to be encountered. In general, however, the proportion should range from four to six parts of the naphthenate to six to four parts of the stearate, respectively. Substantially equal parts of the stearate and naphthenate are preferred.

The invention is not limited to processes and compositions containing the above described specific complex or mixed salts but embraces liquid mineral oil compositions and processes of treating the same in which other mixed salts may be utilized. As has been previously stated, salts of the following metals are useful for the purposes of this invention: aluminum, calcium, barium, strontium, zinc, magnesium, cobalt, cadmium,

acid salts, saturated fatty acid-aromatic carboxylic acid salts, naphthenic acid-sulfonic acid salts, naphthenic acid-phenate salts, naphthenic acid-organo phosphoric acid salts, naphthenic acid-aromatic carboxylic acid salts, sulfonic acidphenate salts, sulfonic acid-organo phosphoric acid salts, sulfonic acid-aromatic carboxylic acid salts, phenate-organo phosphoric acid salts, phenate-aromatic carboxylic acid salts.

Wherever used herein, the term saturated fatty acids" designates saturated acids of the fatty acid series containing more than approximately ten carbon atoms and includes substituted fatty acids, such as phenyl stearic acid. Likewise, the term organo phosphoric acid or organo substituted acids of phosphorus" is utilized to designate acids of phosphorus containing an organic substituent.

Examples of saturated .fatty acid-naphthenic acid mixed or complex salts are: aluminum stearate-naphthenate, calcium stearate-naphthenate, zinc stearate-naphthenate, magnesium stearate-naphthenate, cobalt stearate-naphthenate, cadmium steara'te-naphthenate, manganese stearate-naphthenate, tin stearate-naphthenateand chromium stearate-naphthenate.

Examples of saturated fatty acid-sulfonic acid mixed or complex'salts are: aluminum stearatecetyl anthracene sulfonate, calcium stearatecetyl anthracene sulfonate, zinc stearate-cetyl anthracene sulfonate, magnesium stearate-cetyl anthracene sulfonate, cobalt stearateecetyl an-- thracene sulfonate, cadmium stearate-cetyl an-' thracene sulfonate, manganese stearate-cetyl anthracene'sulfonate, tin stearate-cetyl anthracene sulfonate, and chromium stearate-cetyl anthracene sulfonate.

Examples of saturated fatty acid-phenate mixed or complex salts are: aluminum stearateeetyl phenate, calcium stearate-cetyl phenate,

' zinc stearate-cetyl phenate, magnesium stearatemanganese, tin and chromium. The invention embraces, for example; the following combinations or mixtures: saturated fatty acid-naphthenic acid salts, saturated fatty acid-phenate. salts, saturated fatty acid-organo phosphoric cetyl phenate, cobalt stearate-cetyl phenate, cadmium stearate-cetyl phenate, manganese stearate-cetyl phenate, tin stearate-cetyl phenate, and chromium stearate-cetyl phenate.

Examples of saturated fatty acid-organo phosphoric acid mixed or complex salts are: aluminum phenyl stearate-cetyl phosphate, calcium phenyl 'stearate-cetyl phosphate, zinc phenyl stearatecetyl phosphate, magnesium phenyl stearate-cetyl phosphate, cobalt phenyl stearate-cetyl phos-. 'phate,.cadmium phenyl stearate-cetyl phosphate, manganese phenylstearate-cetyl phosphate, tin phenyl stearate-cetyl phosphate, and chromium phenyl stearate-cetyl phosphate.

Examples of saturated fatty acid-aromatic carboxylic acid mixed orcomplex salts are: aluminum stearate-cetyl' benzoate, calcium stearatecetyl benzoate, zinc stearate-cetyl benzoate, magnesium stearate-cetyl benzoate. cobalt stearatecetyl benzoate, cadmium .stearate-cetyl benzoate, manganese stearate-cetyl benzoate, tin stearatecetyl benzoate, and chromium stearate-cetyl benzoate.

- Examples of naphthenic acid-sulfonic acid mixed or complex salts are: aluminum naphthenate-cetyl anthracene sulfonate, calcium naphthenate-cetyl anthracene sulfonate, zinc naphthenate-cetyl anthracene sulfonate, magnesium naphthenate-cetyl anthracene sulfonate, cobalt naphthenate-cetyl anthracene sulfonate, cadmium naphthenate-cetyl anthracene sulfonate, manganese naphthenate-cetyl anthracene ionataand chromium naphthenate-cetyl anthracene sulfonate.

Examples of naphthenic acid-phenate mixed or complex salts are: aluminum naphthenatecetyl phenate, calcium naphthenate-cetylphenate, zinc naphthenate-cetyl phenate, magnesium naphthenate-cetyl phenate, cobalt naphthenatecetyl phenate, cadmium naphthenate-cetyl phenate, manganese naphthenate-cetyl phenate, tin

naphthenate-cetyl phenate, and chromium naph- Examples of suifonic acid-phenate mixed or complex salts are: aluminum cetyl phenatepetroleum sulfonate, calcium cetyl phenate-petroleum sulfonate, zinc cetyl phenate-petroleum sulfonate, magnesium cetyl phenate-petroleum sulfonate, cobalt cetyl phenate-petroleum sulfonate, cadimum cetyl phenate-petroleum sulfonate, manganese cetyl phenate-petroleum sulfonate, tin cetyl phenate-petroleum sulfonate, chromium cetyl phenate-petroleum sulfonate, aluminum cetyl phenate-cetyl anthracene sulfonate, calcium cetyl phenate-cetyl anthracene su1fonate, zinc cetyl phenate-cetyl anthracene sulfonate, magnesium cetyl phenate-cetyl anthracene sulfonate, cobalt cetyl phenate-cetyl anthracene sulfonate, cadmium cetyl phenatecetyl anthracene sulfonate, manganese cetyl phenate-cetyl anthracene sulfonate, tin cetyl phenate-cetyl anthracene sulfonate, and chromium cetyl phenate-cetyl anthracene sulfonate,

Examples of sulfonic acid-organo phosphoric acid mixed or complex salts are: aluminum cetyl phosphate-petroleum sulfonate, calcium cetyl phosphate-petroleum sulfonate, zinc cetyl phosphate-petroleum sulfonate, magnesium cetyl phosphate-petroleum sulfonate, cobalt cetyl phosphate-petroleum sulfonate, cadmium cetyl benzoate-petroleum sulfonate, zinc cetyl benzoate-petroleum sulfonate, magnesium cetyl benzoate-petroleum sulfonate, cobalt cetyl benzoatepetroleum sulfonate, cadmium cetyl benzoatepetroleum sulfonate, manganese cetyl benzoatepetroleum sulfonate, tin cetyl benzoate-petroleum sulfonate, chromiumscetyl benzoate-petroleum sulfonate, aluminum cetyl benzoate-cetyl anthracene sulfonate, calcium cetyl benzoatecetyl anthracene sulfonate, zinc cetyl benzoate- .cetyl anthracene sulfonate, magnesium cetyl benzoate-cetyl anthracene sulfonate, cobalt cetyl benzoate-cetyl anthracene sulfonate, cadmium cetyl benzoate-cetyl anthracene sulfonate, manganese cetyl benzoate-cetyl anthracene sulfonate, tin cetyl benzoate-cetyl 'anthracene sulfonate, and chromium cetyl benzoate-cetyl'anthracene sulfonate.

Examples of phenate-organo phosphoric acid mixed or complex salts are: aluminum cetyl phenate-cetyl phosphate, calcium cetyl phenatecetyl phosphate, zinc cetyl phenate-cetyl phosphate, magnesium cetyl phenate-cetyl phosphate, cobalt cetyl phenate-cetyl phosphate, cadmium cetyl phenate-cetyl phosphate, manganese cetyl phenate-cetyl phosphate, tin cetyl phenatecetyl phosphate, and chromium cetyl phenatecetyl phosphate.

Examples ofphenate-aromatic carboxylic acid mixed or complex salts are: aluminum cetyl phenate-cetyl benzoate, calcium cetyl phenatecetyl benzoate, zinc cetyl phenate-cetyl benzoate, magnesium cetyl phenate-cetyl benzoate, cobalt cetyl phenate-cetyl benzoate, cadmium cetyl phenate-cetylbenzoate, manganese cetyl phenate-cetyl benzoate, tin cetyl phenate-cetyl benzoate, and chromium cetyl phenate-cetyl benzoate.

The combinations herein disclosed yield lubricants having improved characteristics which are not obtainable with metal salts having single organic acid components. In general, the combinations of this invention cooperate to give lubricants having one or more improved characteristics as compared with lubricants using the single elements of the combinations. For example, mixed salts having a fattyacid component give improved lubrication value or resistance to wear and enhanced protection of bearings operating under severe conditions. Combinations containing phenate components have lower corrosion and greater stability at elevated temperatures than do oils containing a fatty acid salt alone, for instance. Also, the phenate components increase the stability of the Q11 solution of the fatty acid salts and the like. The organo phosphoric acid component increases the stability of the oil to high temperatures and its resistance to oxidation, as well as improves wetting and adhesion characteristics of the oil to hot. metallic surfaces. This component also reduces the corrosivity of the oils toward copperlead or cadmium-silver bearing metal alloys. Certain of the sulfonates reduce friction, corrosion, and enhance oxidation stability of particular combinations. The phenates and sulfonates tend to reduce jell-formation of other components of the combinations in certain instances.

The phenates used in the combinations of this invention are preferably high molecular weight compounds in which the phenolic radical contains at least eleven carbon atoms. The organo phosphate compounds are also preferably high molecular weight materials in which the acid of spontaneous ignition of Diesel fuels.

carbon compositions and the proportion of the metal salts should therefore preferably be insufficient to solidify the hydrocarbon mixture. In general, it has been found that from approximately 0.5% to approximately 2% of totalfsalt content; based on the weight of the hydrocarbons, serve the purposes of the invention although as little as 0.1% was much as 5% is not precluded.

The metal salts may be incorporated in high boiling hydrocarbons of widely different types. Hydrocarbons of petroleum origin are the most commonly available and will be most generally utilized. Pennsylvania, Mid-Continent or California petroleums are suitable sources for high boiling hydrocarbons of the type here involved. Although paraffinic oils such as commonly obtained from Pennsylvania crudes arenot precluded, it has been fliund that acid refined naphthenic base oils are more readily susceptible to improvement as respects formation of adhesive resinous deposits on metal surfaces at elevated temperature. Synthetic hydrocarbons, for example, olefin hydrogenated polymers such as butene, isobutene or mixed butene hydrogenated polymers, may be utilized. In general, the hydrocarbon should be of a liquid consistency at ordinary atmospheric temperatures andshould preferably have a boiling point above approximately 500 F. at atmospheric pressure.

The relative proportion of the respective acid components in th complex or mixed salts contained in the compounded lubricating oils herein disclosed will vary, depending upon the purposes to be served and conditions encountered during use. In general, the ratio of acid components will be no greater than ten to one, and preferably will be from approximately four to one, on the one hand, to one to one, on the other handthes being stoichiometrical proportions.

The compositions of this invention have a number of applications and will be found to have utility where it is desirable to inhibit deposition and/or formation of adhesive gums on metal surfaces which are bathed in or are in contact with high boiling hydrocarbons subjected to elevated temperatures in the presence of an oxidizing agent such as an oxygen-containing gas. One example of such an application comprises the lubrication of Diesel engines in which the oil is spread in a thin film over the pistons, piston rings and cylinder walls of the engine, and is subjected to the oxidizing action of the compressed gases in the combustion chamber at temperatures of from approximately 425 to 525 F. or above which exist at the upper piston rings of such engines. In this particular application of the invention it should be noted that the hydrocarbons are subjected not only to high temperatures in thin films on the metal surfaces, but also to the high pressures necessary to produce These pressures are approximately 400 to 600 lbs/sq. in. at the time of ignition of the fuel, and rise to pressures as high as 750 to 1150 lbs./sq. in. during combustion of the fuel. By the present process the normal course of reactions occurring in the oil under these conditions may be progressively altered so that formation and/or deposition of adhesive materials is prevented and piston ring sticking is inhibited.

The compositions of this invention are also applicable to the prevention of formation and/or deposition of adhesive materials from hydrocarbon mixtures in those various instances where an oil flows over a metal surface which is heated to high temperatures and where heat transfer is the primary object to be accomplished. For example, oil cooled electric resistances subject the oil to high temperatures at the oil-metal interface of the highly heated electric resistance element. The deposition of adhesive gummy materials on the surface of the resistance element may be inhibited at temperatures as high as 425 to 525 F. and the efliciency of the heat transfer thereby maintained or increased. 'An oxidizing agent will generally be present in such heat transfer process by reason of dissolved oxygen which is contained in the oil being. heated, as I .well as by reason of air which may be in contact with the oil at one or more points in the system. The compounding agents herein disclosed. may

have one or more advantages depending upon the particular compounds selected, the proportion utilized, and the environment which the compounded oil is to encounter. It should be observed, for example, that even though a compounded oil may be somewhat corrosive to copper-lead or cadmiuimsilver bearing metals, Babbitt bearings are little if at all affected by such corrosive action at temperatures where they are not. unsatisfactory for other reasons, such as low melting point or lack of fatigue resistance. Hence, compounded oils which'may not be particularly desirable for lubrication of copper-lead or cadmium-silver bearings may be highly useful I and extremely advantageous in conjunction with the operationof internal combustion engines having bearings of Babbitt or other corrosionresistant bearing'metals. The present invention,

in its broader aspects, is therefore not limited to combinations having all or the greatest number of advantages, but embraces various of the less advantageous combinations which will find utility in particular applications where all the possible improvement in properties may not be required or where the standard of performance may not be so high. Y

The mixed salts of this invention may be added to hydrocarbon oils containing other compounding ingredients, such as pour point depressors,

blooming agents, compounds for enhancing the viscosity index of the hydrocarbon oil, etc. The

invention in its broader aspects embraces hydrocarbon oils containing, in addition to the mixed salts herein disclosed, thickening agents in greaseforming proportions or in'amounts insufficient to form greases, as in the case of mineral castor machine oils or other compounded liquid lubricants. Apart of the subject matter of thi application is disclosed in the original specification of applicants earlier application Serial No. 62,814 now issued as Patent No. 2,163,622 of June 26, 1939, on compounded lubricating oil. This common subject matter was divided out of parent case No. 62,814 for inclusion in the present application.

' Our copending application Serial No. 476,056,

filed February 16, 1943, is directed to those aspects of the invention relating to the combination of sulfonates and organo-phosphate and to the combination of suli'onates and naphthenates or aromatic carboxylates.

While the character of this invention has been described in detail and numerous illustrations given, this has been done with the intention that no limitation should be imposed upon the invention thereby. It will be apparent to those skilled in the art that numerous modifications and variations oi the above disclosures may be effected in the practice of the invention which is 01' the scope of the claims appended hereto.

We claim:

A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing from approximately 0.1% to approximately 5% by weight based on the oil of oil-soluble mixed salts oi aluminum having a naphthenic and a saturated higher fatty acid radical, said mixed salts being present in an amount suilicient substantially to reduce said deposition.

2. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containin in an amount suiilcient substantially to reduce said deposition, oil-soluble mixed salts of aluminum having as one radical a high molecular weight phenate radical.

3. A compounded liquid lubricant comprising high molecular weight substituted acid of phosphorus containing an organic substituent.

4. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount sufficient substantially to reduce said deposition, oil-soluble mixed salts of aluminum having a sulfonate and a phenate radical.

6. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount suflicient substantially to reduce said deposition, oil-soluble complex salts of a polyvalent metal and having as one component a radical of a substituted acid of phosphorus containing an organic substituent.

7. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount sufficient substantially to reduce said deposition, oil-soluble mixed polyvalent metal salts having a sultonate and a phenate radical.

8. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount sufllcient substantially to reduce said deposition, oil-soluble mixed salts selected from the group consisting of aluminum, calcium, barium, strontium, zinc, magnesium, cobalt, cadmium, manganese, tin and chromium salts containing a naphthenic and a saturated higher fatty acid radical.

9. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration at elevated temperatures, said hydrocarbon oil containing in an amount sufiicient substantially to reduce said deterioration, oil-soluble mixed salts of a polyvalent metal, said mixed salts having as salt-forming acid radicals a substituted acid of phosphorus containing an organic substituent and an organic carboxylic acid containing an aryl substituent.

10. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount sufficient substantially to reduce said deposition, oil-soluble mixed salts of aluminum having an alkaryl sulfonate and a phenate radical.

11. A compounded liquid lubricant comprising a liquid hydrocarbon oil subject to deterioration and deposition of adhesive materials at elevated temperatures, said hydrocarbon oil containing, in an amount sufiicient substantially to reduce said deposition, oil-soluble mixed polyvalent metal salts having an alkaryl sulfonate and a phenate radical.

GEORGE L. NEELY. FRANK W. KAVANAGH.