US2223932A - Lubricating oil - Google Patents

Description

Patented Dec. 3, 1940 UNITED STATES LUBRIOATING on.

Charles C. Towne, Beacon, N. Y., assignor to The Texas Company, New York, N. Y., a corporation of Delaware No Drawing.

Application December 20, 1937,

Serial No. 180,830

11 Claims.

This invention relates to a lubricant, and more particularly to a lubricating oil of the character of a motor oil.

One of the principal objects of the invention is to provide an improved lubricating oil of this character which is effective to reduce normal engine wear.

Another object ofthis invention is to provide certainnovel compounds which are valuable as additives for lubricating oil for this purpose.

Other objects and advantages of the invention will be apparent from the following description and the accompanying claims:

In accordance with the present invention, a small proportion of a polyvalent metallic derivative of a beta-diketone is added to the lubricating oil to improve its lubricating qualities. The metallic beta-diketones of this invention have the following structural formula:

in which M is a polyvalent metal, R1 is an alkene or naphthene group containing six or more carbon 25 atoms, and R2 is an alkyl group. R1 is preferably oleyl or naphthenyl, or homologues thereof. R2 is generally methyl, but may be a higher homologue thereof such as ethyl, propyl, etc. M is preferably copper, zinc, aluminum, tin, calcium or cadmium. Wherever the above formula is used in the description and the claims, it is to be understood that this is set forth in the simplest form with M representing a 'monovalent metal satisfying the second valence of the oxygen atom attached to the carbon of one of the ketone groups; and that in the case of a polyvalent metal derivative, where the metal has a valence in excess of one, the additional valences of the metal are satisfied by linking to additional simi- 40 lar di-ketone groups through the oxygen attached to the carbon of each respective di-ketone group. Examples of metallic beta-diketones which have been found effective in accordance with the present invention include, aluminum naphthenoyl acetone, zinc naphthenoyl acetone, zinc oleoyl acetone and tin naphthenoyl acetone.

In order to definitely identify the above enumerated compounds, the method of manufacturing the same is described.

The zinc oleoyl acetone was prepared as follows: Methyl oleoyl ketone was first prepared by passing a mix of one part of oleic acid and two parts of acetic acid througha catalyst bed of pumice containing deposited manganese oxideat a temperature of 425 F. The reaction products were condensed and ether and caustic soda solution added. The ether layer containing the dissolved methyl oleoyl ketone was separated and stripped of the ether. This methyl oleoyl ketone was refluxed with commercial ethylacetate con- (Cl. 252-53) taining a small amount of ethyl alcohol in the presence of metallic sodium, and then poured into water and acidified with acetic acid. The top layer of ethylacetate containing the dissolved dike tone was separated, and the ethyl acetate evaporated to leave the oleoyl acetone as a residue. The zinc salt was prepared by dissolving the oleoyl acetone in ethyl alcohol containing dissolved potassium hydroxide, and then solid zinc chloride added and the mix stirred. 0r the zinc chloride may be first dissolved in alcohol, before being added to the alcoholic solution of caustic potash containing the oleoyl acetone. A precipitate of the zinc oleoyl acetone was thereby obtained, which was extracted with benzol and stripped to obtain the purified zinc oleoyl acetone as a brown liquid.

In the manufacture of the aluminum, zinc and tin naphthenoyl acetones, methyl naphthenoyl ketone was first prepared by passing a mixture of about one part of naphth'enic acids obtained from heavy residual naphthene base mineral oil and two parts of acetic acid through a catalyst bed of pumice containing deposited manganese oxide at a temperature of 400 F. The condensate obtained stratified into an oil layer and an aqueous layer which were separated, and the oil layer shaken with caustic soda, washed with water and then extracted with ether.

The extract was stripped of the etherto obtain aluminumand tin salts were prepared by dissolving the naphthenoyl acetone in benzene and adding anhydrous aluminum chloride and stannic chloride respectively. Water wasadded, and the top layer formed upon stratification in each case was decanted and filtered through clay to remove suspended impurities; The clear filtrate was dehydrated by shaking with anhydrous potassium carbonate, and the benzene then stripped off to obtain the aluminum naphthenoyl acetone as a brown sticky residue, and the stannic naphthenoyl acetone also as a brown sticky residue;

The beta-diketones of the saturated fatty acids, such as acetyl acetone from acetic acid andpal- "mitoyl' acetone from palmitic acid, and certain metallic derivatives thereof, have heretofore been prepared. However, so far as I am aware, the

beta-diketones of higher unsaturated fatty acids, such as oleic acid, and or naphthenic, acids such as obtained from petroleum, and their corresponding metallic derivatives, are novel products. These latter compounds are superior to the previously known products of this class for purposes of this invention in that they have greater solubility in mineral lubricating oil, and also possess greater efiectiveness in reducing engine wear when compounded in a motor oil. 1

The metallic diketones of this invention are dissolved in a mineral lubricating oil in a proportion of 0.1-5.0% by weight. Generally a. proportion of about 0.501.0% is preferred. The compounded oil is found to be markedly improved with respect to engine wear when used as a crankcase lubricant for an internal combustion engine. This is illustrated by tests made on a single cylinder 0. F. R. engine operating with a jacket temperature of 80 F. for a period of hours with fully opened throttle. Before the test, the engine is taken down, the piston rings cleaned and weighed. After the test, the engine is again taken down, and the rings cleaned and weighed. The difference in weight is computed as mgs. of ring wear. The crankcase oil after the test is also analyzed for total iron in the oil, this giving an, indication of the combined wear of the piston, cylinder, piston rings and related parts. In making this test the unblended reference oil is first run, then a blended oil to be compared therewith is run, following which an un- Oil tested Ring wear Iron in oil Ma. Ma.

Reference oil-furfural refined dewnxed Mid-Continent lubricating oil, 8. A. E.

20 (average of 5 runs) 191 303 Reference oil+l.07 zinc oleoyl acetone (average of 5 runsg 72 213 Reference oil (average of 3 runs) 151 Reference oil+l.0% zinc naphthenoylacetone (average of 3 runs) 95 Reference oil (avers e of 5 runs) 298 603 Reference oil+1.0 0 aluminum naphthenoyl acetone (average of 3 runs) 164 397 Second reference oil (average of 3 runs)... 193 520 Second reference oil+0.5% stannlc naphthenoyl acetone (average of 2 runs) 148 463 These results may be summarized as percentage better than the reference oil as follow Additive I Ring wear Iron in oil Percent Percent 1.0% zinc oleogl acetone 63 1.0% zinc nap thenoyl acetone 37 1.0% aluminum naylsuhthenoyl acetone. 45 p 51 0.5% stannic napht enoyl acetone 29A 7 While the above enumerated tests show somewhat erratic results, by taking an average of a number of runs for any particular reference oil or any particular blended oil, and by also alternating a run on a reference oil with a run on a blended oil, an accurate trend of the effectiveness of the additive in reducing engine wear is indicated. It is felt that this constitutes the most accurate practical test for showing engine wear yet developed; and the results clearly indicate a decided reduction in wear for the oil compounded with the metallic diketones of the present invention.

' ing oil containing a small proportion of a metallic beta-diketone having the formula 0M Ri- J=cn-oom in which M is a polyvalent metal, R1 is a hydrocarbon group selected from the class consisting of alkene derived from the higher unsaturated fatty acids, and naphthene derived from naphthenic acids, and R2 is an alkyl group.

2. A lubricant comprising a mineral lubricating oil containing iii-5.0% by weight of zinc naphthenoyl acetone.

3. A lubricant comprising a mineral lubricating 011 containing 0.1-5.0% by weight of aluminum naphthenoyl acetone.

4. A lubricant comprising a mineral lubricating oil containing (LL-5.0% by weight of zinc oleoyl acetone.

5. As a new product, a metallic beta-diketone having the formula OM Ri( J=CHC -I in which M is a polyvalent metal, R1 is a hydrocarbon group selected from theclass consisting of alkene derived from the higher unsaturated fatty acids, and naphthene derived from naphthenic acids, and R2 is an alkyl group.

6. A new product in accordance with claim 5 in which M is selected from the-group consisting of copper, zinc, aluminum, tin, calciumand cadmium, and in which R1 is naphthenyl.

7. The method of lubricating the bearings and cylinders of an internal combustion engine which comprises supplying to the bearings and cylin ders of said engine a mineral lubricating oil containing a small proportion of a. metallic betadiketone having the formula in =CH-COR: A in which M is apolyvalent metal, R1 is a hydrocarbon group selected from the class consisting of alkene derived from the higher unsaturated fatty acids, and naphthene derived from naphthenic acids, and R: is an alkyl group.

8. The method as defined in claim '7 in which M is selected from the group consisting of copper, zinc, aluminum, tin, calcium and cadmium, and in which the metallic beta-diketone is present in the proportion of (Ll-5.0% by weight.

9. A motor 011 comprising a mineral lubricating oil containing a small proportion of a polyvalent metal derivative of a beta-diketone containing a. hydrocarbon group derived from one of the class consisting of the higher unsaturated fatty acids and naphthenic acids.

10. A motor oil as defined in claim 9 in which the hydrocarbon group is naphthenyl.

11. A motor oil as defined in claim 9 in which the hydrocarbon group is oleyl.