US2487151A - Lubricant composition - Google Patents

Description

Patented Nov. 8, 1949 v LUBRICANT COMPOSITION Eugene Lieber, New York, N. Y., and Aloysius F. Cashman, Bayonne, N. J assignors to Standard Oil Development Company, a corporation of Delaware No Drawing. Application September '7, 1945, Serial No. 615,082

13 Claims. (Cl. 252-52) This invention relates to the preparation of novel chemical products and to uses thereof, more particularly to the preparation of wax modifiers useful as pour depressors for waxy mineral lubricating oils. Heretofore, pour -de-' pressors have been made commercially in several different ways, but chiefly by the condensation of chlorinated paraflin wax with some aromatic compounds such as naphthalene or phenol, but the resulting products, although having good pour-depressing potency as determined by the standard A. S. T. M. pour point test, have not generally had as good pour stability as might be desired. This latter test has been described in the Oil and Gas Journal, June 24, 1943. For instance, it has been found that a blend of a waxy mineral lubricating oil containing a small amount of such pour depressor may have an A. S. T. M. pour point as low as 30 F., but may show a solid point as high as +10 F. or even +20 F. when measured by the Test V procedure for pour stability. The difference between the two tests is chiefly that in the A. S. T. M. pour point test the oil blend is heated once to insure complete solubility of all constituents, then gradually cooled down once, determining the lowest temperature (within 5) at which the blend jected to a number of alternate heating and" to 50%, preferably about. to This range of chlorine contents produces a mixed chlorinated product containing mono-, di-, tri-,

and even traces of higher chlorwax molecules.

cooling cycles, the cooling always being down to the same low temperature of about 25 F. while the upper temperature to which the sample is permitted to warm in each cycle is progressively lower from 30 F. in the first cycle, down to 0 F. in the sixth cycle.

One object of the present invention is to make from chlorinated wax a pour depressor which has better pour stability characteristics.

It has now been found that superior pour depressors are obtained by condensing the chlorinated wax with a fatty acid halide such as stearyl chloride, either by heat alone or with a catalystr The product having an average chlorine content corresponding to a dichlorwax is preferred, al-

though it is known to contain some mono and some trichlorwax molecules. Instead of chlorinated wax, one may also use chlorinated, brominated, or other halogenated derivatives of other higher aliphatic hydrocarbon materials such as petrolatum refined liquid petroleum fractions of the kerosene or higher boiling range, or mono or polyhalo derivatives of individual pure hydrocarbon compounds, e. g. octadecyl chloride, cetyl chloride, lauryl chloride etc. In general, these aliphatic halides may be represented by the formula RXn where R represents an aliphatic or essentially aliphatic hydrocarbon radical, X represents halogen and n represents a number indicating the average number of atoms of halogen attached to R through aliphatic carbon linkage.

Instead of using stearyl chloride which has.

the formula CrzHasCOCl, one may use other .monobasic fattyacid chlorides having the general formula RCOCl, where It represents an aliphatic or essentially aliphatic hydrocarbon group, which may be a saturated, i. e. alkyl group or av slightly unsaturated aliphatic group. Examples of such acyl chlorides include palmityl chloride,

-oleyl chloride, phenyl-stearyl chloride, naphthylstearyl chloride, chlorides derived from cocoanut 011 fatty acids, or from fatty acids of other oils such as linseed oil, cottonseed oil, soybean oil, etc. It is also possible to use polybasic acid halides having the general formula (CH2) n(COX) 2 where X is halogen and n is an integer of one i acyl halides which may be used may be grouped under the general formula R'(COX)m, where R represents a mono-, di-, or higher valent aliphatic, aromatic-aliphatic or otherwise essentially aliphatic hydrocarbon group, X represents halogen and 112 represents the number or average number of COX groups attached to the R group.

The proportions in which the halogenated aliphatic hydrocarbon and the fatty acid halide are to be co-condensed may vary to some extent accordin to the halogen content of the former and the number of acyl halide groups in the latter, but generally should range from about 0.2 to 5, preferably .5 to 2.0 mols of the halogenated aliphatic hydrocarbon to one mol of the fatty acid halide. For most of the various materialswhich are generally available within these two classes, the proportions by weight should be about 20 to 300, preferably about 50 to 150 parts by weight The co-condensation of the fatty acid halideand the aliphatic halide may be carried outby heating the mixture of the two materials to a temperature of about 400 F. to 700 F., preferably about 500 F. to 600 F. for a sufficient reaction time range from about 0.1 to hours which varies inversely with the temperature used. The mixture should generally be heated until the evolution of hydrogen chloride or other hydrogen halide has substantially ceased. While a suitable product can be prepared without the use of a catalyst, it is often desirable to use one to promote the speed of polymerization and/or condensation, and in particular, catalysts of the Friedel-Crafts type are preferred, e. g. aluminum chloride, zinc chloride, boron fluoride, tetanium tetrachloride etc. Finely-divided solid adsorbents, such as Attapulgus clay, bauxite, silica gel, activated alumina, kieselguhr, etc., and also finely-divided metals, such as Raney-nickel, iron powder, etc., may be used, alone or with a Friedel- Crafts type catalyst, although these adsorbents per se are not as efiective as the Friedel-Crafts type catalyst. If .a catalyst and/or adsorbent is used, a slightly lower reaction temperature may be used. e. a. about 250 F. to 500 F. in the.

case of a Friedel-Crafts catalyst such as aluminum chloride.

Normally, it is not necessary to use a solvent for carrying out the reaction, but optionally this may be done, and in such a case, suitable inert solvents may comprise a saturated liquid petroleum hydrocarbon fraction such .as a refined heavy naphtha or kerosene or a highly chlorinated hydrocarbon such as tetrachlorethane, di-

chlorbenzene, etc.

After the desired co-condensatlon has been completed, as evidenced by the cessation of hydrogen halide evolution, the desired condensation product may be recovered from the reaction mixture by any suitable means, but preferably by cooling the reaction mixture, diluting it with a suitable solvent such as a refined kerosene, tetrachlorethane, etc., filtering and then distilling the reaction mixture under reduced pressure, e. g., up to about 500 F. under fire and steam distillation, or up to 500 F. or higher under a vacuum corresponding to an absolute pressure at least as low as mm. mercury, and preferably as low as 10 mm. mercury, to remove solvent and low-boiling products, as well as unreacted raw materials. If a Friedel-Crafts ty pe catalyst has been used, it should be hydrolyzed and removed by settling, centrifuging or other- 4 wise, prior to the distillation of the reaction product.

The resulting co-condensation product, which is generally a dark, viscous oily to waxy solid material, should generally have an average molecular weight of at least about 600, and preferably ranging from about 1,000 to 5,000. It is soluble in mineral oils, and has good waxmodifying properties, being especially valuable as a pour depressor in waxy mineral lubricating oils for making blends having good pour stability at low temperatures. For this purpose, the amount to be used should normally range from about 0.05% to 2%, and preferably about 0.1% to 1.0% or 1.5%. modifier in other hydrocarbon materials, particularly other petroleum hydrocarbon fractions, such as gas oil, Diesel fuel or even kerosene, 0r

:normally solid fractions such as paraflin wax,

invention is not well understood, but it is believed that number of different chemical reactions take place simultaneously during the cocondensation of the aliphatic halide and the fatty acid halide. For instance, it is believed that the fatty acid halide per se undergoes auto-condensatlon, and the aliphatic halide, e. g., chlorinated paraflin wax, may also undergo auto-condensation by splitting off hydrogen halide withthe resultant formation of olefin hydrocarbon groups which then polymerize; and thirdly, it is believed that the chief reaction is actually a cocondensation of the fatty acid halide molecules with aliphatic halide molecules, with the resultant formation of a chain-like high molecular weight condensation product having more or less alternate distribution of the radicals from the two different raw'materials as they become freed of hydrogen halide during the heating. These various condensation products may build up to molecules of various molecular weights, and also there may be some .interlinking between or among them, so that the final product is likely quite complex in nature. 7

The objects, advantages and details of the invention will be better understood from a 'consid-' eration of the following experimental data.

Three series of preparations are presented, one in which no catalyst has been used, the second in which aluminum chloride is used as a catalyst, while in the third group Attapulgus clay is used as a catalyst. In each series three different proportions of reactants were used, but the same general procedure was used for all of the nine tests, except that the second series included a catalyst hydrolysis with diluted hydrochloric acid solution.

The .chloro-wax (prepared from .118" .F, M. P. wax and containing 14.5% C1) and stearyl chloride were heated in a Kieldahl flask to 300-310 C. for 2 /2 hours. The reaction .flask was then cooled anddiluted with 500 cc. of tetrachlorethane andfiltered through paper. The product was recovered by vacuum distillation to 300 C. bottoms temperature under a pressure of 9 mm. Hg. A yield of 83 grams of a brown oily wax was obtained as product.

The products prepared as described above were blended in several concentrations in two waxy oils having an A. S.T. M. pour point of +30 F., and the pour points of these blends were determined, the results being set forth in the following table. a

It may also be used as a wax 'Table .A. s. T. M. Pour Points o I (Sli 7 m5. 01'0- Test No. 3 Stearyl Wax Catalyst Per cent in A Oil Per cent in B Oil Chloride (133% 86 100 57 -20 -15 5 +15 57-85 100 83 -15 +5 0 +5 87 50 54 15 10 0 +5 +15 98 100 95 15 -10 0 +5 +5 +10 97 100 51 10 0 0 +5 +15 99 100 --d0 104 +10 +20 +20 +10 +15 +20 101 100 50 10 gums. Atta- 59 -10 0 +10 +5 +15 +15 p gusc ay. 100 100 100 ...(10 69 +5 +5 +15 +5 +15 +20 102 50 100 (10 69 +15 +15 +30 +25 +25 +25 N OTE: A oil is a Pennsylvania neutral total distillate.

bright stock. 1

, As will be noted, efiective materials can be prepared without using a catalyst and, in general, Attapulgus clay is the least effective of the materials used. The products prepared as described above have been found to have superior pour stability properties when compared to the ordinary pour depressants available commercially, for example, pour depressors A and B, which are wax-naphthalene and wax-phenol condensation products respectively.

Pour stability properties of the pour depres-' sants prepared asdescribed above (tests 2 and 5) were tested at Minneapolis, Minn. and Warren Pa. during the winter. The test oil comprised a mixed base neutral oil +3.5% Penna. bright stock. Two sets of blends were tested, namely 0.5% and 1.0% of the product in the given test oil and the overall pour stability ratings were obtained. Pour stability rating is the percent of the time the blends are observed to be fluid for the period of observation. Thus a rating of 100 indicates that the particular blend was observed to be fluid at all observations whereas a rating of 0 indicates that the blend is solid at all observations.

A more detailed comparison of the individual blends emphasizes the superiority of the present invention.

Minneapolis Warren Gone. 7

Times ggg Times ggfig Solid Point's]? Solid Points]? Your Depressor 0.5 44 +20 41 +23 A. 1.0 47 +20 37 +22 Pour Depressor 0.5 31 +20 23 +20 B. 1. 0 38 +20 16 +22 Present Inven- 0.5 2 +12 0 Below -l3 tion, Test 2. 1. 0 8 +22 I 3 0 Present Inven- 0.5 1 +8 0 Below ---19 tion, Test '5. 1.0 3 +21 7 B oil is 50% of 11" oil plus 50% Pennsylvania aflinic materials alone will not produce efl'ective pour depressants. To demonstrate this, the chlorinated paraflin wax used in the above preparations was heated to the same reaction temperatures but without the fatty acid chlorides being present. In all cases, products were recoveredhaving no pour depressant potency as measured by the A. S. T. M. pour test and, in addition, the yields of pyrolyzed products were very much smaller in the absence of fatty materials. The improvements in pour stability properties are due to the presence of fatty acid radicals withthe paraffinic materials.

It is not intended that this invention be limited proportion of a waxy mineral lubricating oil and 0.05% to 2% of a co-condensation product of about 20 to 300 parts by weight of a chlorinated paraifin wax containing about 10% to 20% of chlorine, with about parts by weight of a an average molecular weight of at least about 600 and being substantially non-volatile up to about 400 F. under a reduced pressure corresponding to an absolute pressure at least as low as about 20 mm. mercury, and said condensation product having been made by reaction of said two reactants at a temperature between the approximate limits of 400 F. and 700 F.

2. Composition consisting essentially of a major proportion of a waxy mineral lubricating oil and 0.05% to 2% of a co-condensation product of about 50 to parts by weight of chlorinated parafiin wax having a chlorine content of about 12% to 16%, with about 100 parts by weight of stearylchloride, said condensation product having an average molecular weight of about 1,000 and having wax-modifying properties, and having been made by reaction of said two reactants at a temperature of about 500 to 600 F.

3. A product consisting essentially of a dehydrohalogenation condensation product of a halogenated paraffin wax and a monobasic fatty acid halide having the general formula R(COX), where R is a saturated aliphatic hydrocarbon radical containing at least 10 carbon atoms and X is a halogen, said dehydrohalogenation occurring at a reaction temperature of about 400 F. to 700 F. for a period ranging from 0.1 to 10 hours, said condensation product being soluble in minmonobasic acyl chloride having at least about 8; carbon atoms, said condensation product having 7 eral oil and having an average molecular weight of at least 600.

4. A product consisting essentially of a condensation product of about 50 to 150 parts by weight of chlorinated paraffin wax containing from about to 20% of chlorine with about 100 parts by weight of stearyl chloride, said condensation product having an average molecular weight of at least 1000 and being soluble in a waxy mineral lubricating oil, said condensation product being prepared by the reaction of said reactants at a temperature between the approximate limits of 400 F. and 700 F. for a period of 0.1 to 10 hours.

5. A product according to claim 3 being a condensation product of about 20 to 300 parts by weight of chlorinated paraffin wax per 100 parts by weight of fatty acid halide.

6. A composition consisting essentially of a major proportion of a waxy lubricating oil and 0.05 to 2% of a co-condensation product of about 20 to 300 parts by weight of chlorinated paraffin wax containing about 10 to 20% of chlorine with about 100 parts by weight of stearyl chloride, said condensation product having an average molecular weight of at least 600 and being substantially non-volatile up to about 400 F. under a reduced pressure corresponding to an absolute pressure of at least as low as 20 millimeters of mercury and said condensation product having been made by the reaction of said two reactants at a temperature between the approximate limits of 400 F. and 700 F.

7. A co-condensation product formed by cocondensing a monobasic fatty acid halide having at least 10 carbon atoms and a halogenated saturated parafiin wax at a temperature between the approximate limits of 400 F. and 700 F. for a period ranging from 0.1 to 10 hours.

8. A product according to claim 7 in which the halogenated paraflin wax contains about 10% to 50% of halogen.

9. A product according to claim 7 in which the halogenated parafiin wax contains about 10% to 20% chlorine.

10. A ctr-condensation product formed by cocondensing a monobasic fatty acid chloride having the general formula R(COC1) in which R represents an aliphatic hydrocarbon group having more than 10 carbon atoms with a chlorinated paraffin wax having a chlorine content of 10% to 20% using a reaction temperature of 400 F. to 700 F. for a period of time ranging from 0.1 to 10 hours and recovering from the reaction mixture a condensation product having an average molecular weight of at least 600.

11. A co-condensation product formed by cocondensing stearyl chloride with chlorinated paraffin wax having a chlorine content of about 10% to 20% using a reaction temperature of about 500 to 600 F.

12. A co-condensation product formed by cocondensing stearyl chloride with chlorinated paraffin wax having a chlorine content of about 10% to 20% using a reaction temperature of about 500 to 600 F., extracting the reaction mixture with tetrachlorethane after the reaction is completed as indicated by the cessation of hydrogen chloride evolution, filtering the extracted reaction mixture .and subjecting the extracted solution to distillation under reduced pressure up to a temperature of at least about 400 F.

13. A product according to claim 12using about to 150 parts by weight of chlorinated paraflin wax having a chlorine content of 12% to 16% for parts of stearyl chloride.

EUGENE LIEBER. ALOYSIUS F. CASHMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,899,582 Mark Feb. 28, 1933 1,939,995 Lincoln Dec. 19, 1933 2,137,664 Bayer Nov. 2, 1938 2,251,550 Lieber Aug. 5, 1941 2,330,064 Lieber Sept. 21, 1943

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