US2444947A - Lubricant - Google Patents

Description

Patented July 13, 1948 g SerialNo. 524,378

This invention relates to lubricants and-additives fon'lubricating'oils and greases. v 7 Additives for lubricating oils'are known in the art vvhich'act to inhibitthe formation of sludge and acid in oil, to prevent the deposition of lacquer 'or varnish on the moving p'art's'fa'fid to prevent other'forms "of deteri oration'offfthe oil which have an undesirable effect on" the device being lubricated, "such as an i internal co-rnhus tionengine. The oil'scontaining suchadditives; V

as a generahrule, are notrequiredto lubricatesurfaces operating under'high pressures and in prep'a'rihglthis type of additive, it is notcoinmorr to consider, this aspect'of"the lubric'ating properties of the'oil. Additives for lubricating oils? and greaseshave also'been proposed heretofor'whichiare especiaF ly' adapted to lubricatesuriaces operated under high pressures, such as gear surfaces. These have; for impart, Pfpropertie'sjand whichalsoinhibit v detrioratio" Because of adverse conditions of operation; 'suc additives can be used, for-example, in; geai boie which operate at relatively high temperatures? 11 The provision of' s'uch additivesffbr' af plurality' or purposes isdesi-rable even thoughfmoi'e thari' 'one iunction'is not mamfest at any one time] Such' an 'add-itiveftvhich? is of a universal matter, canbe stockedb t user for 'a'plur-ality of purposes, thus avoiding the purchase land use of aj' nur'nber'of I difi'erentfaddi-' tives'forfspecial purposes It is a principal obje'ctof th'e 'invntion thereof to provide a new compositionsuitableforuse as a lubricant fa'n'df also asari:tdditive' for lubricating oils and-"greases to-iinpr'ove their ESP; properties and also toin'hibit the formation ofsl'udge, acid; lacquer ahdoth ei' results attributablet'o the deterioration 'offft'he o11 um1;er operating 'con di leanin (01. 252-421 Other objects and advantages of the'invention will appear from th'e f'o-llowing description of the invention."

In accordance with the present invention it has been found that a halogenated ox ygen 'contaming-organic compound may be reacted-with phosphorus sulfide and. the reaction product'then converted into a heavy metal compound thereof. The resulting product hasbeen found" to' befohtainabl ein good yields "and to' have improved properties with respect to the inhibition; of acid and sludge formation and" particularly the inhibition of lacquer" formation, and also imparts these properties to lubricating oils and greases to which the product'is added. Furth-ermorathe productan d lubricating oils and greasescontain the samehi l E. P.'properties; It is recognized that it has-been proposed'here tofore to use a wide variety of halogenated com-'- pounds as so-called E: P. additivesm Such E; P:

lubricants are not used normally as' additives' in oils -"for' hig'h'temperature operation, such as'in an internal combustion engine, because high pressures are noflencounteredfi In add-itionfun der 4; these conditions of operation, many of" these'E; P:

lubricants are excessively corrosive; The latter property is not of much concern because under conditions in which: such E. P. lubricantsare normally used,jcorrosion is not a problem. ;-Thus,

Th? nvention cdntempla'ts' additives which the halogenated-materialswhich heretofore have beensuggestedas having good' E. 'P-. properties ordinarily are not good inhibitorstfor sludge "and acid formation in 0115.- v

It is also recognized that many sulfur=corrtai'riing additives have been proposed and that metal compoundsthereof have been suggested as acid, sludge, and lacquer inhibitors. However; the additives which are used for these purposes ordinarilydo not impart: E. P; properties-Ito foils and greases and are not used for this purpose because apparatus operating under conditions normally con duciveto sludge, acid, and lacquer formation doesnot' operate at high pressures-i;

In View of this state of the art, it is unexpected t'hat' a material could'impart E. P. properties to oils and greases and yet the same material func'-' tion to inhibit the formation of sludge,--acid, lacquer, corrosion; and other difficultiesi which are inherent in high temperature operations.

The halogenated V oxygen-containing organic 3 compounds that may be used in accordance with the invention may be any of a wide variety of compounds falling in this class. Preferably, these materials should have a sufilciently high molecular weight to have a boiling point of at least about 300 F. There is no upper limit to the molecular weight of the compound except that high polymers are not preferred, and the halogenated-oxygen-containing organic compound should be one which results in a reaction product with phosphorus sulfide that is soluble in the oil or grease which is to be used. In general, most of the halogenated oxygen-containing organi compounds themselves are oil soluble.

As illustrative of the compounds falling in this class, reference may be made to halogenated oxygen-containing acids, both aliphatic and aromatic, such as chlorobenzoic acid, dichlorobenzoic acid, chloronaphthenic acid, monoand di-chloropalmitic acid, monoand di-chlorostearic acid and di-chloro dihydroxy stearic acid.

As illustrative of the halogenated oxygen-con,- taining organic esters, there may be mentioned amples of these metals are arsenic, lead, copper, iron, zinc, tin, antimony, and bismuth. These are readily available and relatively inexpensive and, therefore, would probably comprise the metals that are used in the commercial adaptation of the invention.

The product of the invention is preferably made in two stages or reaction steps. In the first step, the halogenated oxygen-containing organic compound is reacted with the phosphorus sulfide. This reaction product is then converted into the desired corresponding metal compound thereof.

In carrying out the reaction between the halogenated oxygen-containing organic compound and'the phosphorus sulfide, the reaction conditions, should be adjusted and the proportions of methyl di-chlorostearate, chlorinated alkyl esters l.

of benzoic acid, such as chloromethyl benzoate, chlorinated esters of monoatomic alcohols of fatty acids, such as chlorobutyl propionate, and chlorinated glyceride of fatty acids, such as chlorinated vegetable oils.

Especially suitable are halogenated oxygencontaining waxes of the ester type, such as chlorinated degras, chlorinated sperm oil, chlorinated hydrogenated waxes. One commercially available hydrogenated sperm oil has an iodine value of 6-7, a melting point of 50-52 C., a free fatty acid content (as oleic) of 1.02.0%, a saponification value of 135-138, and about 36% of unsaponifiables. Another commercially avail able product is made by treating hydrogenated sperm oil to remove a portion of the glycerides therefrom. This product will be referred to hereinafter as refined hydrogenated sperm oil. It has an iodine value of 6.0, a melting point of 48-50 C., a free fatty acid content (as oleic) of 0.4%, a saponification value of 125, and 45% of unsaponifiables.

Additional examples of halogenated oxygencontaining organic materials include chlorinated alcohols and phenols, ketones, aldehydes, and other compounds.

Any of the above compounds may be used in admixture with each other or in admixture with other compounds in which the halogenated oxygen-containing organic compound is a predominant ingredient thereof. Preferably such a compound or mixture should be "saturated because the compounds with too high an iodine value tend to polymerize under the reaction conditions.

Halogenated oxygen-containing organic compounds have been referred to generally as a class and compounds of any halogen may be used. Chlorinated compounds are the most economic and competitive and since they give satisfactory results the respective chlorinated compounds have been listed as illustrative.

Of the phosphorus sulfides available, phosphorus pentasulfide is relatively inexpensive and readily available commercially. Inasmuch as desirable results are obtained with it, the invention is described using phosphorus pentasulfide as illustrative.

The heavy metal compounds, as these are defined herein, include any metal other than the alkali metals and alkaline earth metals. Ex-

the material should be selected so as to obtain a reaction product having a substantial amount of 20- sulfur.

In the preferred embodiment, a temperature is employed which is high enough to replace a major portion of the oxygen of the organic compoun'djwith sulfur. The observed facts appear to indicate a reaction in which at least a part of the sulfur of the sulfidereplaces oxygen of the halogenated oxygen-containing organic compound and at least part of the displaced oxygen combines with the phosphorusto form a phosphorous and oxygen-containing residue.

.The temperature which should be used varies somewhat depending primarily upon. the molecu lar weight of the halogenated oxygen-containing organic compound and the rate that itis desired to have reaction effected. In view of these variables it is impossibleto assign a precise numerical temperature that is optimum for all of the compounds, but in general the temperature should be above about 270 F., preferably in the range of 290 to 310 F. Temperatures in excess of 350 .to 400, F, are not essential and there is no point in using a'higher temperature than that which causes, the reaction to proceed smoothly in the desired length of time. I

The amount of phosphorus sulfide to be used in the first step of making the product, preferably should be at least about equivalent to the theoretical amount that would be required to replace all of the oxygen in the halogenated oxygen-containing organic compound with sul fur. The amount of the sulfide will vary with the molecular weight and the amount of oxygen in the compound so that the precise amount involves simple chemical calculations. A slight excess over the theoretical amount of the sulfide, for instance, about 10% or more, may be of as: sistance in forcing the reaction to completion.

After the initial reaction between the halogenated oxygen-containing organic compound and the sulfide, a residue comprising phosphorus and. oxygen will settle out as a sludge together with any other insoluble materials and the reaction product may be decanted or may be separated by filtering or centrifuging.

Theseparated reaction product is then converted into the corresponding heavy metal compound as described heretofore. The metal, preferably, is in the form of the oxide or hydroxide.

The amount of the metal compound to be employed will depend somewhat on the molecular weight of the metal compound and the initial reaction product. Generally the amount will vary from 1 to 15% depending upon these factors. The amount of the metal compound will also depend on whether the reaction product is to an raew beicompletely or partially reacted vwiththe-metal? :compoundi It desired the" amount of the: metal compound may be such as-only to react w-ith a part of the initial reaction'producti so. as to form a mixture of the initial reaction product and-the metal compound thereof. Such-a mixture is ad vantageous under some 1 circumstancessinoe it embodies the propertiestof both ingredientsi The initial reaction'product can also be treated with arplural-ity' of the above metals -and'=the:plurality' of metals *may inc1ude"one'0f-*the' heavier metals with a minor proportionof an: alkali or alkaline: earth metal. Incases oi-certain oflthe heaviermetals, the oxides or hydroxides of which maynot" be reactive-the initially reacted product may be converted into an alkali metal compound thereof and this may be reacted with a salt of the heavier metalto replace the" alkaliymetal to formthe desired heavier metal compoundi- If desired,'onlya part of the .alkali cr' alkaline earth: metal may be" replaced and in: this-*way a mixture of two metals may be formed.- V

Inmaking' the metal compounds the initialreaction-product;-preferably after...it has been separated from theresidu'e', ishea'te'd' to a-t'temper'ature'of about 180 to- 350 preferably 300 F; and the metal: compound added. i i I The reaction" is continued'until the desired amount of the metal compoundisincorporated; which may be from 1 to '8' hours. The reaction mixture is then settled or centrifuged and'the metal compound is separated from: any unreacted metal oxide orother insoluble materials. 1

The. amount of the above described metal com-- pound to be added to oils or greases depends upon thecharacteristics of the oil or grease'and theintended-use'thereof. Generally,- the amount will be within the range of 0.=51to*15%, but under some circumstances much smaller amounts show a: noticeable improvement. Inasmuch as: themetal compound itselfis a lubricant, there is no: upper'limit to=the amount that maybe used: It is: uneconomical, however, to add more than is necessary to impart the desired properties to the The @following: specific. exampleis; included merely as illustrative of the invention, but'without limiting the scope of the invention as other-H wise described and defined-herein: 1

Example] (A) Chlorinated refined hydrogenated'sperm oil containing'30% chlorine is reacted with 20% of phosphorus pentasulfide atjatemperatur'e of 300 F. After the reaction iscomplete, which requires about 1 hourgthe material'was permitted to stand, during which'time a by-product residue settles and the reaction product was decanted.

' (B)'The above reactionproducti was reacted with 5% arsenic trioxide by heatingat a tempera ture of 300 F."for about ;1 hour. The mixture was filtered to separate the metalcompound from any impurities. v 1

In order to evaluate the metal compound as an inhibitor in a lubricating oil, and'also to determine its capacity for imparting E. P. properties, it was added in'an amount of 9% 'to an oil comprising 60% PennsylvaniaBright Sto 'cl-:'and.40% No. 300 Red Oil. This'was'compared-with the same oil, not containingan additive, with the same oil containing 9% of the same chlorinated refined hydrogenated sperm oil, and with t he same oil containing 9% of the initial'reaction product. 1

Air, fuel ratio 15:1?- Compression ratio 7'; 1 l- 5 I Catalyst r ,r- 0.1% FezOsas Neoldex'i' Y iron. naphthenat'ef The results'of this test are as follows? n the' above t'est'it was necessary tdui the operation-of the' engine at'the enddFZO hours with the oil containing chlorinated refiner '1i y 5l1*o--- genated sperm oil since thevisco'sity of this oll increased su-chthat the" engine couldnot ther lubricated; With theadditiveof'tlie'inve tion made inaccordance with the'inventionjthe run could be coritinuedfor a'mucli' lon g erfti The metal" compound-0f the invention" ism U superior from the standpoint of corrosion as co U pared with "clorinatedmefine d" l'iydrogenaitedfsperrn oil, and is also superior to the reactionf product thereof Withphosphoru's penta'lsulfiole".

' The"'-same samples'were tested by theiTitii 11"} test at800" R; P. M. to evaluate their E. Pi'prop'- erti'esi; The results are as follows: I,

From 'the' above-data'it will be seen that the metalficompoun' ds of the invention are "superior-, both in their properties and'theii' inhibition to deterioration of'theoil', 1 T I This superiority in 'both 'these respectsi's in dependent of the chlorine content of the refined" hydrogenated sperm oil 1 Similar tests carried out with chlorinated refinedhydrogenated sperm oil containing.'10% chlorine revealed result's of the same order; namely, they" demonstrate" the? superiority of Ithe' metal compound as imparting: to the 'oil" an: improved resistance against" 06F" rosiorrofrthe:bearings and higlierE.v roperties'ss Y The? manner "in which the invention would be applied to other halogenated oxygen containingr starting materials and" other metals vwi1lbe= -ob-- vious' from the above example in view or thEFdis-A closureheretofore; and: io'r'this reason 'furtheriexamples'areno'tinclud'ed,"

It will 'be apparent to one skilled in" the artf that a-=va-riet'y of materials are included? within" thegeneric' designations and that different pro c'edures be'includ'ed; All such variations as fall: within the scope of; the following claims. are-in tended tob'e -iricluded in the" invention.

application is a continuation-impart of? The inhibiting characteristics of the three our applicatiorr'seri'al Numberi48z 4 lqfiledmprtfi 7 9,1943, now Patent No. 2,419,153, dated April pound reacted with an amount of a phosphorus sulfide at least about equivalent to the theoretical amount required to replace the oxygen in the halogenated oxygen-containing organic compound with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue.

2. As a lubricant and as an addition agent for lubricating oils and greases to inhibit their deterioration and improve their E. P. properties, a heavy metal compound of the reaction product of a chlorinated oxygen-containing organic compound reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated oxygen-containing organic compound with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue. 7

. 3. As alubricant and as an addition agent for lubricating oils and greases to inhibit their deterioration and improve their E. P. properties, a heavy metal compound of the reaction product of a chlorinated fatty acid reacted with an amount of a phosphorus sulfide at least about equivalent to thetheoretical amount required to replace the oxygen in the chlorinated fattyacid with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a. phosphorus and oxygencontaining by-product residue.

4. As alubricant and as an addition agent for lubricating oils and greases to inhibit their deterioration and improve their E. P. properties, a heavy metal compound of the reaction product of a chlorinated ester of a fatty acid reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount re .quired to replace the oxygen in the chlorinated -.fatty acid ester with sulfur from the sulfide, re-

acted ata temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue. a

5.. As a lubricant and as an addition agent for lubricating oils" and greases to inhibit their deterioration and improve their E. P. properties, a heavy metal compound of the reaction product of a-chlorin-ated ester type wax reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in. the chlorinated ester type wax with sulfur from the sulfide. reacted at a temperature above 270 F. to form a reaction product which isseparable from a phosphorus and oxygen-containing by-product residue.

6. As a lubricant and as an addition agent for lubricating oils and greases to inhibit their deterioration and improve their E. P. properties, the arsenic compound of the reaction product of a chlorinated ester type wax reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated ester type wax withsulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue.

7. As a lubricant and as an addition agent for lubricating oils and greases to inhibit their deterioration and improve their E. P. properties, the arsenic compound of the reaction product of a chlorinated hydrogenated sperm oil reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated hydrogenated sperm oil with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing byproduct residue.

8. A lubricating composition comprising a min eral oil lubricant and an amount of an addition agent to inhibit the deterioration and improve the E. P. properties thereof, said addition agent being a heavy metal compound of the reaction product of a halogenated oxygen-containing organic compound reacted with an amount of a phosphorus sulfide at least about equivalent to the theoretical amount required to replace the oxygen in the halogenated oxygen-containing organic compound with sulfur from the sulfide, reacted at a. temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue.

9. A lubricating composition comprising a mineral oil lubricant and an amount of an addition agent to inhibit the deterioration and improve the E. P. properties thereof, said addition agent being a heavy metal compound of the reaction product of a chlorinated fatty acid reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated fatty acid with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable froma phosphorus and oxygen-containing by-product residue.

10. A lubricating composition comprising a mineral oil lubricant and an amount of an addition agent to inhibit 'the'deterioration and improve the E. P. properties thereof, said addition agent being a heavy metal compound of the reaction product of a chlorinated ester of a fatty acid reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated fatty acid ester with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing by-product residue.

11. A lubricating composition comprising a mineral oil lubricant and an amount of an addition agent to inhibit the deterioration and improve the E. P. properties thereof, said addition agent being a heavy metal compound of the reaction product of a chlorinated ester type wax reacted with an amount of phosphorus pentasulfide at least about equivalent to the theoretical amount required to replace the oxygen in the chlorinated ester type wax with sulfur from the sulfide, reacted at a temperature above 270 F. to form a reaction product which is separable from a phosphorus and oxygen-containing byproduct residue.

12. A lubricating composition comprising a mineral oil lubricant and an amount of an addition agent to inhibit the deterioration and im- 10 prove the E. P. properties thereof, said addition agent being the arsenic compound of the reac- REFERENCES CITED tion product of a chlorinated ester type wax re- Ih following references are of record in the acted with an amount of phosphorus pentasulfide file of this patent: at least about equivalent to the theoretical 5 UNITED STATES PATENTS amount required to replace the oxygen in the chlorinated ester type wax with sulfur from the Number Name Date sulfide, reacted at a temperature above 270 F. 2,252,934 Rutherford u 9, 94:1 to form a reaction product which is separable 2,242,250 fi n May 20, 941 from a phosphorus and oxygen-containing by- 10 2,331,923 Musselman Oct. 19, 1943 product residue 2,307,183 Zimmer et a1. Jan. 5, 1943 2,342,432 Smith et a1 Feb. 22, 1944 JOHN M. MUSSELMAN. ,3 8 Whittier July 4, 1944 HERMAN P. LANKELMA. ,2 Reifi Aug. 8, 1944