US2227952A - Sulphurized oil - Google Patents

Description

Patented Jan. 7, 1941 sonrmnuzsn on John 0. Ziminer, Hillside, N. 1., assignorto Standard Oil Development Company, a corporation of Delaware No Drawing. Application July 20, 1938,

- Serial No. 220.267

it claims; (mesa-46) The present invention relates to improved sulphochlorinated oils and to methods for making the same. The invention will be fully understood from the following description:

It has been'knowniormany years that sulphur and chlorine increased the load bearing capacity i of oils for lubrication of hypoid and other gears where high or extreme pressures may be encountered, metal working and the like and many such oils have been and are now used for these purposes. In some cases mineral oils have been sulphurized directly; in others fatty oils such asrlard and fish oils are sulphurized and are added to the mineral bases. Both of these products serve the purpose but at the same time have many disadvantages; for example, it is diflicult to add enough sulphur to mineral oils'to give suflicient load bearing capacity, without encountering sulphur separation when the product is cooled. sulphurized fatty oils containing more than 10 to 12% of sulphur have a very foul odor which is objectionable in cutting oils and the like, and if the sulphur content is reduced the extreme pressure properties are greatly impaired. Morebver, their blends in mineral oil do'not possess sufiicient extreme pressure properties 'for satisfactory lubrication of automotive hypoid gears, and the sulphurized fatty oil is often" not' completely soluble in mineral oil andtends to separate in storage and service. i Y Similar difficulties occur with the various other sulphurized bases which have been suggested from time to time.

It has now been found that these difliculties can be overcome by using as the base to be sulphurized a solvent extraction product of petroleum. The extract is obtained by the use of solvents such as phenol, cresol, dichlor ethyl ether, aniline, sulphur dioxide, nitro benzol, fur- 40 fural, and the like, which various solvents with others, too numerous to specifically mention, make up the class of extraction solvents which are used to separate liquid parafllnic constituents from non-paraffinic fractions. The extracts may '45 be obtained from petroleum fractions such as kerosene, gas oils, and the light and heavy lubricating'fractions. The quality of the extract I depends of course to some extent upon the crude from which it is obtained and the intensity of the extraction treatment, but for present purposes it has been found thatan extract having a viscosity index below about i? is suitable for the purpose, although it is preferred to use ma terials having a lower viscosity index,. forexample below '0, 5 or -l0,- or even lower. The

extracts may be obtained from parafiinic, naphthenic, or mixed. asphaltic "base type of crude oils. In general the preferred stocks are those rich in natural sulphur, for. example, the origi- 6 ha] sulphur content varies from say 0.6 ,to-3 or 4% of the extract.

The extract is preferably purified first by treatment with sulphuric acid in thesame way that most mineral oils arerefined. This removes the more unstable asphaltic products and gives a 1.0 much more desirable stock to sulphurize. Ordinarilyfrom 5 to 15 pounds of acid per barrel are used in the preliminary treatment.

The mineral oil extract is sulphurized by treatment with a suitable sulphur halide among which 15 sulphur monochloride is the most suitable. The extract sulphurizes much more readily than an ordinary mineral oil, in fact so readily that great care should be taken to prevent. too vigorous action which tends to formation of insoluble,

sludge-like products. This is best accomplished by limiting the amount of sulphur chloride used to approximately 5 to 15% 01' the extract. With amounts up to 5% of the extract there is little 25 or no sludge and more may be used but there is p I an increasing tendency to :sludge.- This is offset to some degreexby. the first stepoi sulphuric acid refining, but tor-*most purposes eilectivecompounds which are stable and possess'goodexgo treme pressure'qualities may be made with approximately 5%. of sulphur chloride; Broadly, however, a greater range of sulphur chloride is useful, for exampleup to- 20 or'25%. The temperature of treatment is from about F. to 35 about 300 F. and, as stated before, the reaction is rapid and vigorous, much more so than is usually the case with mineral oil. It'has been found'that the extraction products referred to above may be used alone asthe sul- 40 phochlorinated stock, or it may be used to replace a certain amount of the fatty oil which has previously been employed. In some in stances, it is desirable to have some of the fatty 45 oil present and in these cases the extraction product and the fatty oil may either be sulphurized separately and mixed or may be ad-" mixed and sulphurized together, for example,'in

the standpoint of freedom from obnoxious odor and improved load carrying capacity.

The sulphochlorinated stock and the mineral lubricating oil containing the same may be used for many purposes. They may be employed in cutting oils or in oils used for other processes of metal working such as stamping, drawing and the like, wherever, in fact, sulphurized or sulphochlorinated oils are now employed, and the degree of sulphurization of the base and the amount of the base in the mineral oil may vary considerably depending on the particular use to which the oil is to be placed. Ordinarily the oil should contain from about 0.40% to 1.50% Cl and 2.5% to 4.0% S. The stock may also be used for gear lubrication, especially for the lubrication of steel gears operating under high pressures, for example in the automotive ditlerentials or othergear units employing hypoid or other types of gears. For these purposes it is frequently desirable to add to the oil a soluble lead compound such as lead naphthenate or lead. sulphonate, or their equivalents. Zinc soaps or mixture of zinc and lead soaps may be employed with advantage. Suchmaterials should be added after the sulphurized stock has been cooled so as to prevent immediate reaction of the sulphur or chlorine with the lead, it being desired to obtain the materials in separate compounds in the final oil which is free from suspended solids.

The oils described andproduced as above have excellent extreme pressure qualities which are not rapidly lost during the normal use of. the oil which is one of the chief objections to many of the products now available." These oils show no separation of solids and the viscosity index of the finished blend is not so greatly reduced by the-use of a sulphurized extract as would be supposed. For example, where an unsulphurized extract is added to a mineral oil of 95 to 100 V. I. in quantity sufficient to give a reduction in viscosity index from '10 to '75, it has been found that after sulphurization, the same amount oiv the extract produced a blend of from to V. I. In addition, the compounds are extremely stable during use even when subjected to oxidation. Many of the oils used at the present time oxidize so rapidly as to become solid after a few hours of severe oxidation or in severe high temperature gear service. These oils, however, have been found to thicken onlysllghtly during such treatment.

In order to further illustrate the nature of the present products and the methods bywhich they are made, the following examples are offered:

Example I A solvent extract of a light petroleum lubricating oil obtained by treatment with phenol had the following characteristics:

This material was treated with 10 pound of sulphuric acid to the barrel of oil, after which two separate samples were treated with 5 and 7.5% respectively of sulphur monochloride. Temperature was maintained at 240 to 260 F. during the treatment which required 2 hours.

The products were cooled and gave the following analyses:

No 1 No 2 Acid treated phenol extract percent.. 72. 5 Sulphur monocliloride o... 5 7. 5 Gravity 15.1. 13. l Vis. F. Say. sec 1,080 l, 383 Vis. 210 F 60 75 Sediment .percent. 0.10 1. l4 Sulphur do.. 3. 27 3.78 Chlorine .do.. 72 1. 14

Example II The two products prepared as in Example I were blended with equal volumes of mineral lubricating oils, and the inspections of the mineral oil used and of the two blends are as follows:

- Mineral Mineral g f oil blend all blend 50% No. 1 50% N o 2 Gravity! P. I degrees.. 4%. l

til. 2 58. 7 42 45 l. 63 l. 80 0. 36 0. 57 Sediment .d0 i 0. 03 0. 40

These blends were subjected to the Almen test with the result that again both carried the full 15 weights when normally applied and when applied under shock conditions.

Example III A solvent extract of a light petroleum lubricating oil obtained by treatment with phenol and having thecharacteristics enumerated in Example I was mixed with an equal volume of No. 1 grade lard oil and then treated with 5% sulphur monochloride. Temperature was maintained at 250 to 260 F. for 2 hours. The product analyzed as follows:

Sulphur per cent 4.39 Chlorine per cent 2.97 Say. Univ. vis. 210 F. sec 191.7

A blend of 10% of the. above in a pale parafiin oil carried 15 weights on the Almen test under shock loading conditions.

Example IV To the blend of sulphur-chloride treated oil last referred to in the previous example, 10% of lead naphthenate is added. This product was an excellent leaded oil for use in lubricant 0f hypoid gears or other severe service. This prodnot carried the full 15 weights on the Almen test when applied under shock loading conditions.

The present invention is not to be limited by any theory of the mechanism of the present sulphurization process nor to the use of any particular ingredients, but only to the following claims in which it is desired to claim all novelty inherent in the invention.

I claim:

1. Process for producing an improved sulphurchlorinated oil comprising reacting a substantially non-asphaltic solvent extraction product oi a petroleum lubricating oil having a viscosity index below at a temperature between 100 and 300 F. with 5 to 15% of sulphur. monochloride until the product contains at least about 0.4% chlorine.

2. An improved process for preparing sulphurchlorinated oil to resist high pressures which comprises blending a substantially non-asphaltic phenol extract of a petroleum lubricating oil with a fatty oil, then reacting the blend with 5 to 5% of sulphur chloride at a temperature of 150 to 300 F.

3. Process according to claim 2 in which 10 to of the extraction product of petroleum is blended with to 25% of a fatty oil and this mixture is subjected to the sulphurization.

4. A process for producing an improved sulphur-halogenated oil comprising reacting a substantially non-asphaltic solvent extract of a petroleum oil fraction at least as heavy as kerosene with a sulphur halide in an amount between about 5% and 25% at a temperature between about 100 and 300 F.

5. Process according to claim 4 in which the extract has a viscosity index below about 50 and is obtained from a petroleum lubricating on which has been acid treated.

6. Process according to claim 4 in which said sulphur halide is a sulphur chloride.

7. Process according to claim 4 in which said sulphur halide is sulphur monochloride.

8. A process for producing an improved sulphur-chlorinated 011 comprising reacting a substantially non-asphaltic phenol extract of a petroleum oil fraction at least as heavy as kerosene with a sulphur chloride in an amount between about 5% and 25% at a temperature between about 100 and 300 F.

9. A process for producing an improved sulphur-chlorinated oil comprising reacting a substantially non-asphaltic phenol extract of a petroleum lubricating oil fraction, said phenol extract having a viscosity index below 50, with a sulphur chloride in an amount between about 5% and 15% at a temperature. between about 100 and 300 F.

10. A composition of matter comprising a sulphur-halogenated oil suitable for use in metal working processes for extreme pressure lubrication, said sulphur-halogenated 011 being prepared by subjecting a substantially non-asphaltic solvent extract of a petroleum oil fraction at least as heavy as kerosene to reaction with a sulphur.

working processes for extreme pressure lubrication, said sulphur-chlorinated oil being prepared by subjecting a phenol extract of a petroleum lubricating oil fraction, said phenol extract having a viscosity index below 50, to reaction with a sulphur chloride in an amount between about 5% and 25% at a temperature between about 100 and 300 F., the resulting sulphur-chlorinated oil containing from about 0.4% to 1.5% chlorine and from 2.5% to 4% sulphur.

14. A composition of matter comprising a sulphur-chlorinated oil suitable for use inmetal working processes for extreme pressure lubrication, said sulphur-chlorinated oil being prepared by subjecting a blend of about 90% to 25% of a fatty oil and 10% to 75% of a solvent extract of a substantially non-asphaltic solvent extract of a petroleum oil fraction at least as heavy as kerosene, to reaction with sulphur chloride in an amount between about 5% and 25% at a temperature between about100 and 300- F.

15. An improved sulphur-and-halogen-compounded oil suitable for use in metal working processes for extreme pressure lubrication comprising a blend of a lubricating oil and the sulphur-halogenated oil described in claim 10.

16. An improved sulphur-and-chlorine-compounded oil suitable for use in metal working processes for extreme pressure lubrication comprising '70 to parts of a mineral lubricating oil