US3676347A - Lubricant and hydrocarbon fuel compositions - Google Patents

Abstract

The stability and cleanliness of lubricating oils under severe thermal and oxidative conditions are improved and the electrical conductivity of hydrocarbon fuels is increased by adding thereto a copolymer of cetyl vinyl ether and N-vinyl-pyrrolidone.

Description

United States Patent Frangaws [451 July 11, 1972 |s4| LUBRICANT AND HYDROCARBON 3.141.222 9/1964 Bauer ..44/63 FUEL COMPOSITIONS Primary Examiner-Daniel E. Wyman [72] Inventor: Gerasslmos Frangatos, Westmont, NJ. Assistant Examiner-Mrs. Y. H. Smith Attorney-Oswald G. Hayes, Andrew L. Gaboriault, Raymond [73] Asslgnee' oncwpmu w. Barclay and Claude E. Setliff [22] Filed: June 19, 1970 21 Appl. No.: 47,900 [571 ABSTRACT The stability and cleanliness of lubricating oils under severe thermal and oxidative conditions are improved and the electrical conductivity of hydrocarbon fuels is increased by adding [58] Field or e a i ..............II4Z}63 62-252751 SR 403 harem a vinyl ether and Y rolidone. [56] References Cited UNITED STATES PATENTS 15 Claims, No Drawings 3,506,574 4/1970 Stambaugh at al. ..44/63 BACKGROUND OF THE INVENTION 1. Field of the Invention This invention, in one of its aspects, relates to organic liquids having desirable anti-static properties. In this aspect, the invention relates more particularly to organic liquid compositions in the form of volatile organic liquids such as hydrocarbon fuels or solvents which possess low electrical conductivity which, when they accumulate electrostatic charges, may give rise to the hazards of ignition or explosion. in another of its aspects, the invention relates to lubricants having improved stability and cleanliness. More particularly with regard to both aspects, the invention relates to the improvement of such organic liquids and lubricants by incorporating therein additives which are eflective in increasing the electrical conductivity of such liquids and in improving oxidative stability and cleanliness of such lubricants.

2. Description of the Prior Art Prior to the present invention, the low electrical conductivity of many volatile organic liquid compositions has presented the problem of controlling static buildup, particularly during handling and transportation, for the purpose of insuring safe and effective distribution without the concomitant danger of ignition or explosion. For example, volatile organic liquids such as hydrocarbon fuel oils (e.g., gasoline, jet fuels, turbine fuels and the like), or light hydrocarbon oils employed for such purposes as solvents or cleaning fluids for textiles, possess a very low degree of electrical conductivity. In the use of such fluids, electrostatic charges, which may be generated by handling, operation or other means, tend to form on the surface, and may result in sparks, thus resulting in ignition or explosion. These hazards may be encountered merely in the handling or transportation of such organic liquids and even in operations, such as centrifuging, in which a solid is separated from a volatile liquid, during which electrostatic charges can accumulate.

Various materials have heretofore been proposed for incorporation into such organic liquid compositions for increasing their electrical conductivity and thus reduce the aforementioned dangers of ignition and explosion. Such materials, however, have not been proved to be sufficiently efl'ective in increasing the desired electrical conductivity of these fluids and, in many instances, have been'found to be too costly for the relatively small degree of increased protection which they are capable of providing.

Lubricating oils are subject to oxidative deterioration at elevated temperatures or upon prolonged exposure to the elements. These lubricants, including mineral oils and synthetic oils, undergo oxidative deterioration in service, especially at high temperatures. This deterioration produces sludges and gums, causes metal parts to corrode and produces loss of lubricating properties of the oil. Many additives of the prior art are only marginally effective except at high concentrations, especially when the oils are subjected to drastic oxidizing conditions.

SUMMARY OF THE INVENTION In accordance with the present invention there are provided lubricating oil and hydrocarbon fuel compositions comprising a major amount of said oil or fuel and an amount sufficient to improve the properties thereof of a copolymer of cetyl vinyl ether and N-vinylpyrrolidone.

DESCRIPTION OF SPECIFIC EMBODIMENTS The "preparation of the aforementioned cetyl vinyl ether-N- vinylpyrrolidone copolymer may be conducted at molar ratios of the monomers of from 1:1 to about :1, i.e., either can vary within this range. It is believed that the structure of the copolymer will conform to the following recurring units where n may vary from 2 to 200. The composition of the copolymer corresponds to the composition of the monomer mixture of the feed.

In general, the invention contemplates the use of from about 000001 percent to about 15 percent of the additive by weight of the fluids disclosed herein. Preferably, the concentration of co-polymer in lubrication oils will be from about 0.01 to about 10 percent by weight thereof, more preferably from about 0.1 percent to about 5 percent. In hydrocarbon fuels, its concentration will be preferably within the range of from about 0.000025 percent to about 0.05 percent by weight thereof. Expressed in another way for the hydrocarbon fuel, the overall range will be from about 0.1 lb. to about 200 lbs. per 1,000 barrels of fuel, and the most preferred will range from about 1 pound to about 10 pounds per 1,000 barrels.

A field of specific applicability of the present invention is in the improvement of organic liquid compositions in the form of petroleum distillate fuel oils having an initial boiling point from about 75 F. to about F. and an end boiling point from about 250 F. to about l,000 F. It should be noted, in this respect, that the term distillate fuel oils is not intended to be restricted to straight-run distillate fractions. These distillate fuel oils can be straight-run distillate fuel oils, catalytically or thermally cracked (including hydrocracked) distillate fuel oils, or mixtures of straight-run distillate fuel oils, napthas and the like, with cracked distillate stocks. Moreover, such fuel oils can be treated in accordance with well-known commercial methods, such as acid or caustic treatment, hydrogenation, solvent refining, clay treatment, and the like.

The distillate fuel oils are characterized by their relatively low viscosity, pour point and the like. The principal property which characterizes their contemplated hydrocarbons, however, is their distillation range. As hereinbefore indicated, this range will lie between about 75 F. and about l,000 F. Obviously, the distillation range of each individual fuel oil will cover a narrower boiling range, falling nevertheless, within the above-specified limits. Likewise, each fuel oil will boil substantially, continuously, throughout its distillation range.

Particularly contemplated among the fuel oils are Nos. 1, and 3 fuel oils, used in heating and as Diesel fuel oils, gasoline, turbine fuels and the jet combustion fuels, as previously indicated. The domestic fuel oils generally conform to the specifications set forth in ASTM Specification D396-48T. Specifications for Diesel fuels are defined in ASTM Specification D975-48T. Typical jet fuels are defined in Military Specification MILF5624B.

The lubricants which may be improved by the addition thereto of the above-mentioned copolymer are mineral oils, both paraffinic and naphthenic, and synthetic oils. The synthetic oils include polyolefin fluids, polyglycols, polyacetals, the siloxanes and the like. Especially useful are those synthetic esters which are becoming more and more popular, particularly in aviation. These include esters made from polycarboxylic acids and monohydric alcohols or from polyhydric alcohols and monocarboxylic acids. Of these the most preferred members are those made from pentaerythritol, or mixtures thereof with di -and tripentaerythritol, and an aliphatic monocarboxylic acid containing from 1 to about 20 carbon atoms or a mixture of such acids.

In broad aspect, the copolymer is prepared by mixing the monomers in a mutual solvent therefor, adding a free radical initiator and heating, preferably at reflux, for the time required to effect the reaction.

Any of the well-known solvents may be used in the synthesis of the copolymer. One such solvent is chlorobenzene. Others will immediately become evident to one skilled in this art, so there is no need for listing them here. These may be selected so that the reaction can be conducted within the range of from about 75 C. to about 250 C., preferably from about 100 C. to about 175 C.

Any of the commonly used initiators may be used. Most common among these, and the ones preferred in the practice of this invention, are the peroxides and the hydroperoxides. Some examples of these are ditertiary butyl peroxide, dicumyl peroxide, azoisobutyronitrile, dilauryl peroxide, diacetyl peroxide, tertiary butyl hydroperoxide, cumyl hydroperoxide and percarbonate esters.

The following examples will serve to illustrate the preparation of the copolymers and their use as antistatic and stability agents.

EXAMPLE 1 Into a reactor was placed 300 ml. of chlorobenzene and 5 grams of ditertiary butyl peroxide was added thereto. The solution was brought to reflux temperature (about 130 C.) and a mixture of 107.2 grams (0.4 mole) of cetyl vinyl ether, 44.4 grams (0.4 mole) of n-vinylpyrrolidone and 100 ml. of chlorobenzene was added to the solution over a period of 45 minutes. Refluxing was continued for 2 hours. The reaction mixture was cooled and left under N pressure overnight.

Two additional grams of ditertiary butyl peroxide were added, the reaction mixture was brought to reflux and was held there for 6 hours. The solvent and unreacted monomer were removed in vacuo (0.3 mm of Hg) at 200 C. for 1 hour. The product (124 grams) was an amber colored fluid, which solidified on cooling.

EXAMPLE 2 Evaluation of Products a. Anti-Static Tests In Hydrocarbon Fuel 1n obtaining the data for the following table comparative electrical conductivity tests were carried out for the purpose of determining the aforementioned property of the Example 1 composition. The test employed for this purpose was electrical conductivity measured in picomhos (i.e. 10 mhos) per meter. In these tests the agent was blended in a liquid hydrocarbon fuel having a boiling range of 300500 F. It was a kerosine of predominantly parafiinic composition, i.e., from 90-95 percent. The resulting fuel composition was evaluated for the degree of improvement in electrical conductivity, as shown in the table.

The startling effect the polymer of Example 1 has on the fuel oil is evident from Table 1. Even at 1.25 pounds he polymer raises the conductivity by a factor of 5. Thus it may be seen that such polymer is an important antistatic agent.

b. Oxidation Test In Synthetic Ester Lubricant The compounds produced in accordance with this invention were blended into a synthetic ester oil lubricant and tested in an oxidation test in accordance with the following procedure.

A sample of the test composition is heated to 450 F. and air at the rate of about 5 liters per hour is passed through for a period of about 24 hours. Present in the test sample are specimens of iron, copper, aluminum, and lead. The kinematic viscosity is measured at 100 F. KV change) and the change in the neutralization number (NN change). It should be noted that the metals are typical metals of engine or machine construction, and they also lplrovide some catalysis for the oxidation of organic materials. e results, tabulated in Table 2, concern the product of Example 1.

Synthetic ester made from pentaerythritol and an equimolar mixture of C and C monocarboxylic acids. It contains about 5 percent of an additive package comprising a major amount of a neutral phosphate ester and lesser amounts ofan amine mixture and a metal suppressor as well as about 0.3 percent ofbis(nonylphenyl) phosphonate.

Iclaim:

1. An organic fluid composition comprising a fluid selected from the group consisting of lubricating oils and hydrocarbon fuels and from about 0.00001 percent to about 15 percent by weight thereof of a copolymer of cetyl vinyl ether and N-vinylpyrrolidone.

2. The composition of claim 1 wherein said copolymer is present in an amount of from about 0.00001 percent to about 15 percent by weight of said fluid.

3. The composition of claim 1 wherein the copolymer is prepared in the presence of a free-radical initiator.

4. The composition of claim 3 wherein the free radical initiator is ditertiary butyl peroxide.

5. The composition of claim I wherein said hydrocarbon fuel comprises a petroleum distillate fuel oil having an initial boiling point from about 75 F. to about 135 F. and an end boiling point from about 250 F. to about 1,000 F.

6. The composition of claim 1 wherein hydrocarbon fuel is gasoline.

7. The composition of claim 1 wherein said hydrocarbon fuel is ajet fuel.

8. The composition of claim 1 wherein said hydrocarbon fuel is a turbine fuel.

9. The composition of claim 7 wherein said jet fuel has a boiling range of 300500 F. and is a kerosine having from about percent to about percent paraffin content.

10. The composition of claim 5 wherein the copolymer is present in said fuel within the range of from about 0.1 to about 200 pounds per thousand barrels thereof.

11. The composition of claim 10 wherein the said range is from about 1 to about 10 pounds per thousand barrels of said fuel.

12. The composition of claim 1 wherein said lubricating oil is a pentaerythritol ester.

13. The composition of claim 12 wherein said ester is prepared from pentaerythritol and a monocarboxylic acid having from about 1 to about 20 carbon atoms or mixtures thereof.

14. The composition of claim 13 wherein the mixed acid is a mixture of acids having from 5 to 9 carbon atoms.

15. The composition of claim 12 wherein the copolymer is present within the range of about 0.01 percent to about 10 percent by weight of the ester.

*zgygg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3A7 Dated July 1972 v Inventofls) Gerassimos Frangatos It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In column 4, Table 2, should appear as follows: w

. Ini- Ini- 1118.1 Final tial Final A KV Oil Additive NN N'N ANN KV KV A* o 0.30 6.90 6.60 27.37 5o. +8 8 mm Signed and sealed this 6th day of February 1973.

(SEAL) Attest:

EDWARD M. FLETCHER,JR. ROBERT GOTTSCHALK Commissioner of Patents Attesting Officer

Claims (9)

1. 3. The composition of claim 2 wherein the free radical initiator is ditertiary butyl peroxide. 4. The composition of claim 1 wherein said hydrocarbon fuel comprises a petroleum distillate fuel oil having an initial boiling point from about 75*F. to about 135* F. and anend boiling point from about 250* F. to about 1,000* F. 5. The composition of claim 1 whereinydrocarbon fuel is gasoline. 6. The compositionf claim 1 wherein said hydrocarbon fuel is a jet fuel.
2. 7. The composition of claim 1 wherein said hydrocarbon fuel is a turbine fuel.
3. 8. The composition of claim 6 wherein said jet fuel has a boiling range of 300*- 500* F. andis a kerosine having from about 90 per cent to about 95 per cent paraffin content.
4. 9. The composion of claim 4 wherein the copolymer is present in said fuel within the range of from abox 0.1 to about 200 pounds p thousand barrels thereof.
5. 10. The composition of clim 9wherein the said range is from abou1 to about 10 pounds per thousand barels of said fuel.
6. 11. The composition of claim 1 wherein said lubricating oil is a pentaerythritol ester.
7. 12. The composition of claim 1wherein said ester is prepared from pentaerythritol and a monocarboxylic acid having from about oneto 20 carbon atoms or mixtures thereof.
8. 13. The composition of claim 12 wherein the mixed acid is a mixture of acids having from five to nine carbon atoms. 14. The composition of claim 11 wherein the copolymer is present within the range of about 0.01 per cent to about 10 per cent by weight of the ester.
9. 15. The composition of claim 12 wherein the copolymer is present within the range of about 0.01 percent to about 10 percent by weight of the ester.