US2316086A - Lubricant - Google Patents

Description

Patented Apr. 6, 1943 LUBRICANT Frederick H. MacLaren, Munster, Ind., assignor to Standard Oil Company, Chicago, Ill., a corporation of Indiana No' Drawing. Application March 24, 1941,. Serial No. 384,946

26 Claims.

The present invention relates to a new composition of matter and particularly to a new composition of matter capable of inhibiting th oxidation of lubricating oils, thereby materially decreasing the susceptibility of such oils to form sludge, carbon and/or varnish-like deposits and further possessing the property of depressing the pour point of the lubricating oil containing the same.

Straight petroleum lubricating oils are efiective within certain defined limits of engine operating conditions but when these limits are exceeded such oils frequently fail to give the desired performance demanded of them. Since, in modern engines designed to give increased performance these limits are frequently exceeded, the use of straight mineral oils as lubricants produce undesirable conditions within the engine. Thus, varnish and carbon formation are excessive and corrosion of improved hard metal alloy bearings is frequently encountered.

In order to provide adequate year-round lubrication, it is frequently the practice to add to lubricating oils addition agents of various kinds which possess the property of depressing the pour point of the lubricating oil. The addition of these pour point depressors in lubricating oils enables the oils to flow freely at relatively low temperatures so that proper lubrication may be attained at these low temperatures.

In order to obtain all of the foregoing desired properties in a lubricating oil, it has been the general practice to add various additives to the oils, each additive imparting to the oil the specific property for which it is intended. Obvious y, such a procedure is time-consuming and uneconomical.

It is an object of the present invention to provide an improved composition of matter possessing the property of depressing the pour point of lubricating oils and also the property of inhibiting the formation of slud e, carbon and/or varnish-like deposits in internal combustion engines. particularly onand about the pistons and piston rings thereof. It is a further object of the invention to provide an improved lubricating oil having a low pour point and which is not susceptible to oxidation and the attendant formation of sludge, carbon or varnish-like deposits in internal com bustion engines, particularly on and about the pistons and piston rings thereof.

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

I have discovered that a lubricating oil additive having the foregoing desired properties may be obtained by reacting a condensation product of an halogenated aliphatic hydrocarbon with an aromatic compound in the presence of aluminum chloride, zinc chloride or other catalyst of the Friedel-Crafts type and subsequently reacting the condensation product with a phosphorus sulfide, such as PzSz, P4S1o, P487, Pisa, or, preferably,

PzSs.

The halogenated aliphatic hydrocarbon is preferably a halogenated long-chain paraffin hydrocarbon having more than eight carbon atoms, such as parafiin'wax, petrolatum, ozocerite wax, etc. High viscosity paraffin oils, particularly heavy residual oil which has been treated with .chemicals or extracted with propane or other solvents for the removal of asphalts, may be employed. The aromatic constituent in the preparation of my starting material may be naphthalene, fluorene, phenanthrene, anthracene, coal tar residues and the like. Halogenated naphthalene or other naphthenic or aromatic compounds equivalent to naphthalene may be used as a condensation reagent in the reaction. The preparation of these condensation products is described in my United States Patents Nos. 1,963,917, 1,963,918, and others.

Other suitable modified condensation products having pour point depressing properties may be reacted with a phosphorus sulfide to obtain the desired addition agent. An example of such modified condensation product is the product obtained by condensing an aromatic hydrocarbon with a chlorinated aliphatic material of relatively high molecular weight such as a chlorinated parafiin wax and subsequently reacting the product thus obtained with an acylating agent and other compounds of the type described in United States Patent 2,147,547.

The additive of the present invention is obtained by reacting a condensation product of the foregoing type with one of the aforementioned phosphorus sulfides, preferably P285 at a temperature of from about 200 F. to about 500 F., preferably from about 300 F. to about 400 F.,

preferably in a non-oxidizing atmosphere. From about 1% to about and preferably fromabout 5% to about 25% of the phosphorus sulfide may be employed. The product so obtained may then -with a basic reagent.

be purified by diluting the same with a diluent, such as hexane, settling, filtering and subsequently freeing the filtrate of the diluent by evaporation or distillation. If desired, any objectionable odor, if present, may be eliminated by blowing the product with nitrogen or steam at elevated temperatures, preferably at 325 F. to 375 F.

The reaction product obtained by reacting a phosphorus sulfide with the condensation product of a halogenated paraflin and an aromatic hydrocarbon will be referred to hereinafter as the condensation product-phosphorus sulfide reaction product.

The condensation product-phosphorus sulfide reaction product may be used as such or it may be further modified by forming a neutralized product. The condensation product-phosphorus sulfide reaction product normally shows a titratable acidity which may be neutralized by treatment The condensation productphosphorus sulfide reaction product when neutralized with a basic reagent containing a metal constituent is characterized by the presence or retention of the metal constituent of the reagent. Other metal constituents such as a heavy metal constituent may be introduced into the neutralized product by reacting the same with a salt of the desired heavy metal.

The term neutralized condensation productphosphorus sulfide reaction product as used herein means a condensation product-phosphorus sulfide reaction product having at least about 1% of its titratable acidity, reduced by the reaction with a basic reagent, and includes theneutralized condensation product-phosphorus sulfide reaction products containing a metal constituent resulting from said neutralization or resulting from the reaction of a heavy metal salt with the condensation product-phosphorus sulfide reaction product treated with a basic reagent.

The neutralized condensation product-phosphorus sulfide reaction product may be obtained by adding to the reaction product a suitable basic compound such as a hydroxide, carbonate, or an oxide of an alkaline earth metal or an alkali metal, preferably potassium hydroxide or sodium hydroxide. Other basic reagents may be used such as. for example, ammonia, or alkyl or aryl substituted ammonia. such as amines. As aforesaid. when the condensation product-phosphorus sulfide reaction product is neutralized with a basic compound containing a metal constituent the neutralized reaction product is characterized. by the presence of a metal constituent of such basic reagent. Neutralized reaction products containing a heavy metal constituent such as. for example, tin, titanium. aluminum, chromium. cobalt, or iron and the like may be obtained by reacting a salt of the desired heavy metal with the condensation product-phosphorus sulfide reaction product which has been treated with a basic reagent.

It will be understood that when the neutraliza tion is accomplished with a polyvalent basic material, such as dime. a product having excess basicity may be obtained.

The preparation .of the additives of the present invention may be illustrated by the following examples which are given by way of illustration and not intended to be a limitation on the scope of the invention.

A condensation product having pour point depressing properties was prepared by chlorinating asiaose a paramn wax having a melting point of "about 130 F. to a chlorine content of about 14% to about 15%. This chlorinated paraflin wax was then mixed with about ten parts by weight of naphthalene and heated to a temperature of at least 130 F. About two to three parts of aluminum chloride was then added to the hot mixture and the mixture agitatedand maintained at the above said temperature until the reaction was substantially completed. The condensation product was then removed from the mixture, neutralized and the water-soluble compounds and loosely bound chlorine compounds removed therefrom.

The above condensation product was then mixed with 10% by weight of phosphorus pentasulfide and the mixture agitated and maintained at a temperature of 240 F. to 315 F. for a period of three hours. The reaction product was then taken up in hexane, filtered, and the filtrate freed of the solvent by evaporation. The final product contained 1.3% phosphorus and 2.03%

sulfur.

EXAMPLE II A portion of the reaction product of Example I before removal of the hexane, was treated with excess alcoholic KOH at a temperature of F., and given several water washes to remove the excess KOH. The product was then filtered, and freed of hexane by evaporation on a steam bath. The final product had a phosphorus content of 1.3%, a sulfur content of 1.2% and a potassium content of 2.51%.

EXAMPLE III To the condensation product of Example I. was added 10% Pass and the mixture heated at 380 F. for eight hours. The product was then diluted with hexane, settled, filtered and the filtrate freed of the diluent by evaporation on a steam bath. The final product had a sulfur content of 1.54% and a phosphorus content of 1.28%.

EXAMPLE IV The reaction product of Example III was diluted in hexane and treated with alcoholic'KOI-I in the manner described in Example II.

EXAMPLE V A portion of th product of Example IV was blown with steam at a temperature of 330 F. to 350 F. for four hours.

The effectiveness of the hereindescribed addition agents is demonstrated by the following engine test. The oils were first subjected to an accelerated engine test made in a standard six cylinder automobile motor operating for sixty hours at 35 B. H. P. and 3000 R. P. M. with an oil sump temperature of about 285 F. At the end of the test period the engine was dismantled and given a visual engine rating. In this visual rating a rating of 10 means that the engine had the appearance of the engine at the start of the test, while a rating of 1 means that the engine after the test was badly coated. Engines having appearances between these extremes are given intermediate rating values. An engine after being lubricated with a good conventional motor oil for a sixty hour period is usually given a visual rating of about 5.

The following oils were subjected to the above test and the data obtained tabulated in Table I. Oil A (control)A high grade SAE 20 motor oil.

Oil B--Oil A+0.25% condensation productphosphorus sulfide reaction product prepared as in Example V above.

Oil C-Oil A+0.'75% condensation productphosphorus sulfide reaction product prepared as in Example V above.

Oil DOil D+0.5% condensation productphosphorus sulfide reaction product prepared as in Example III, +05% of the reaction product prepared as in Example IV.

Table I Unricr- I head carbon I Ringbelt carbon Oil Overall In a second test about 250 cc. of the oil to be tested is heated at about 330 F.-332 F. in a 500 cc. glass beaker in the presence of five square inches of copper and ten square inches of iron. Four glass rods of about six millimeter diameter are suspended in the oil which is stirred at about 1300 R. P. M. with a glass stirrer having a 40" blade pitch. At stated intervals-oil samples are taken and sludge. acidity and viscosity values determined. The glass rods are also inspected for evidence of varnish formation thereon. Varnish values are based on the visual rating in which a glass rod free of any varnish is given a rating of 10, while a badly coated rod is given Rods having appearances between a rating of 1. these extremes are given intermediate values.

The following oils were subjected to the above test and the data obtained are tabulated in Table II.

Oil EHigh grade SAE 20 motor oil. Oil FOil E+0.25% condensation product-phosphorus sulfide reaction product. of Example I.

Oil G-Oil E+0.5% condensation product-phos-- phorus sulfide reaction product of Example I1. Oil H0il E+0.5% product of Example I+0.5%

product of ExampleII.

Table I I Visi cosity 1 increase Slud ge nag/l0 g. oil

Aciditv Varnish ing. KOH/g. oil i rating z 1 4s 12 24 l 48 I 72 24 hrs. hrs. hrs. hrs. hrsv hrs.

24 hrs.

43 hrs. hm

on HT;

l Saybolt Universal viscosity at 100 F.

Table-III Oil Pour'point (ontrol (ontroi-l-0 25% condensation product-P285 reaction product of Example I Control+0.5% condensation productPS,-, reaction product of Example I Control+1.0% condensation pl0dll0t--PgS5 reaction product of Example Control+0.25% neutralized condensation product- P285 reaction product of Example II (ontrol+0.5,--; neutralized condensation product P18 reaction product of Example II. Control+l.0% neutralized condensation pr0duct Pass reaction product of Example II.

The condensation product-phosphorus sulfide reaction products, or the neutralized products thereof may be used alone as lubricating oil additives or they may be employed in combination with other additives. For example, they may be used in combination with the reaction product of a mono-olefin polymer and a phosphorus sulfide, or the neutralized products of the latter, or with the reaction product of a hydrocarbon, such as a. petroleum oil, and a phosphorus sulfide or the neutralized products thereof. They may also be used along with other pour point depressors, sludge inhibitors, antioxidants and other additives for imparting certain desirable properties to lubricating oils.

Although I have described the use of the condensation product-phosphorus sulfide reaction products in lubricating oils, which may be used in such oils in amounts of from about 0.001% to 10.0% and preferably from about 0.01% to about 3.0%, my invention is not limited to such use.

- since these products may be employed in other petroleum products such asinsulating oils, turbine oils, greases, and the like While I have described preferred embodiments of my invention, other modifications thereof may be made without departing from the scope and spirit of the invention, and I therefore do not wish to limit the invention to the examples set forth herein, except insofar-as the same is .defined by the following claims.

I claim:

1. A lubricant comprising a mineral lubricating oil and a small amount of the prosphorus and sulfur-containing product obtained by reacting a phosphorus sulfide with the condensation product resulting from the treatment of a halogenated long chain parafiln with an aromatic hydrocarbon in the presence of a catalyst of the Frieda- Crafts type.

2. A lubricant comprising a mineral lubricating oil and a'small amount of the phosphorus and sulfur-containing product obta ned by reacting a phosphorus sulfide with the condensation product resulting from'the treatment of chlorinated paraffin wax with naphthalene in the presence of aluminum chloride.

3. A lubricant as described in claim 2 in which the phosphorus sulfide is phosphorus pentasul- 4. A lubricant comprising a mineral lubricating oil and a small amount of the phosphorus and sulfur-containing product obtained by reacting a phosphorus sulfide with the condensa tion product resulting from the treatment of a halogenated paraffin with an aromatic hydrocarbon in the presenceof a catalyst of the Friedel- Crafts type and subsequently neutralizing the reaction product of the phosphorus sulfide and the condensation product with a basic reagent containing a metal constituent.

5. A lubricant as described in claim 4 in which the neutralized product contains potassium.

6. A lubricant comprising a mineral lubricating oil and a small amount of the phosphorus and sulfur-containing product obtained by reacting a phosphorus pentasulfide and the condensation product resulting from the treatment of chlorinated paraifin wax with naphthalene in the presence of aluminum chloride and subsequently neu-' tralizing the reaction product of the phosphorus pentasulfide and the condensation product with a basic reagent having a metal constituent.

7. A lubricant as described in claim 6 in which the neutralized product contains potassium.

8. A lubricant as described in claim 6 in which the neutralized product contains sodium.

9. A lubricant as described in claim 6 in which the neutralized product contains calcium.

10. A mineral oil composition comprising a viscous mineral oil and in admixture therewith the phosphorus and sulfur-containing reaction product of a phosphorus sulfide and the condensation product obtained by treating a halogenated long chain paraffin with an aromatic hydrocarbon in the presence of a catalyst of the Friedel-Crafts type, said reaction product being present in an amount suflicient to improve the viscous mineral oil with respect to lowering the pour point, inhibiting oxidation and preventing varnish formation- 11. A mineral oil composition as described in claim 10 in which the reaction product is neutralized.

12. A mineral oil composition as described in claim 10 in which the reaction product is neu-.

tralized with a basic potassium compound.

13. The method of inhibiting the formation of deposits of the type of sludge, carbon and varnish in an internal combustion engine during use comprising lubricating said engine with a lubricant comprising a lubricating oil normally susceptible to form sludge, carbon and varnish in an internal combustion engine during use and a small amount of the phosphorus and sulfur-containing product obtained by reacting a phosphorus sulflde with the condensation product resulting from the treatment of halogenated long chain paraflin with an aromatic hydrocarbon in the presence of a catalyst of the Friedel-Crafts type.

14. The method of inhibiting the formation of deposits of the type of sludge, carbon and varnish in an internal combustion engine during use comprising lubricating said engine with a lubricant comprising a lubricating oil normally susceptible to form sludge, carbon and varnish in an internal combustion engine during use and a small amount of the phosphorus and sulfur-containing product obtained by reacting a phosphorus sulfide with the condensation product resulting from the treatment of chlorinated paraffin wax with naphthalene in the presence of aluminum chloride.

15. The method of inhibiting the formation of deposits of the yp of sludge, carbon and varnish in an internal combustion engine during use comprising lubricating said engine with a lubricant comprising a lubricating oilnormally susceptible to form sludge, carbon and varnish in an internal combustion engine during use and a small amount of the phosphorus and sulfur-containing product obtained by reacting a phosphorus sulfide and the condensation product resulting from the treatment of a halogenated paraflin with an aromatic hydrocarbon in the presence of a catalyst of the Friedel-Crafts type and subsequently neutralizing the reaction product of the phosphorus sulfide and the condensation product with a basic reagent.

16. The method of inhibiting the formation of deposits of the type of sludge, carbon and varnish in an internal combuston engine during use comprising lubricating said engine with a lubricant comprising a lubricating oil normally susceptible to form sludge, carbon and varnish in an internal combustion engine during use and a small amount of the phosphorus and sulfur containing product obtained by reacting a phosphorus pentasulfide with the condensation product resulting from the treatment of chlorinated paraffin wax with naphthalene in the presence of aluminum chloride and subsequently neutralizing the reaction product of the phosphorus pentasulfide and the condensation product with a basic reagent having a metal constituent.

17. The method as described in claim 16 in which the neutralized product contains potassium.

18. A new composition of matter comprising a hydrocarbon oil and the phosphorus and sulfurcontaining product obtained by reacting a phosphorus sulfide with the condensation product resulting from the treatment of a halogenated long chain paraifin with an aromatic hydrocarbon in the presence of a catalyst of the Friedel-Crafts 19. A new composition of matter comprising a hydrocarbon oil and the phosphorus and sulfurcontaining product obtained by reacting a phosphorus sulfide with a condensation product resulting from the treatment of chlorinated paraflln wax with naphthalene in the presence of aluminum chloride.

20. A new composition of matter comprising a hydrocarbon oil and the neutralized phosphorus and sulfur-containing product obtained by reacting a phosphorus sulfide with the condensation product resulting from the treatment of a halogenated paraflin with anaromatic hydrocarbon in the presence of a catalyst of the Friedel-Crafts type and subsequently neutralizing the reaction product of the phosphorus sulfide and the con densation product with a basic reagent containing a metal constituent 21. A new composition of matter as described in claim 20 in which the halogenated parafiin is chlorinated paraflin wax and the aromatic hydrocarbon is naphthalene.

22. A new composition of matter as described in claim 20 in which the neutralized product contains an alkali metal constituent.

23. A new composition of matter as described in claim 20 in which the neutralized product contains potassium.

24. A new composition of matter as described in claim 20 in which the neutralized product contains sodium.

25. A new composition of matter as described in claim 20 in which the neutralized product contains an alkaline earth metal constituent.

26. A new composition of matter as described in claim 20 in which the neutralized product contains calcium.

FREDERICK H. MACLAREN.