US3847827A - Cyclic sulfur-chlorinated oil and process of making - Google Patents

Abstract

1. A PROCESS WHICH COMPRISES REACTING A NORMALLY LIQUID SULFUR HALIDE WITH AN OIL OBTAINED FROM THE CRACKING OF PETROLEUM SAID OIL, CONTAINING AS A MAJOR INGREDIENT POLYNUCLEAR AROMATICS AND BOILING BETWEEN 350 AND 800* F. AND HAVING SEPARATED THEREFROM BY SULFURIC ACID TREATMENT THE MAJORITY OF IMPURITIES WHICH FORM A PERMANENT SLUDGE WHEN REACTED WITH A NORMALLY LIQUID SULFUR HALIDE, AND SEPARATING ANY RESULTING PRECIPITATE AND HYDROGEN HALIDE FORMED THEREFROM TO LEAVE A STABLE AND HOMOGENEOUS CYCLIC OIL HAVING ANTI-WELD PROPERTIES, CHARACTERIZED BY LACK OF OFFENSIVE ODOR AND CONTAINING UP TO ABOUT 20% TOTAL SULFUR AND UP TO ABOUT 5% TOTAL CHLORINE.

Description

United States Patent 3,847,827 CYCLIC SULFUR-CHLORINATED OIL AND PROCESS OF MAKING Robert L. Dinsmore, Long Beach, and Herbert D. Ivey, Pasadena, Calif., assignors to Lubrication Company of America, Los Angeles, Calif. No Drawing. Filed Sept. 10, 1973, Ser. No. 395,741 Int. Cl. C10m N38 US. Cl. 25248.8 11 Claims ABSTRACT OF THE DISCLOSURE A sulfur-chlorinated cyclic oil having anti-weld properties, and being useful as a cutting or lubricating oil is produced from an oil having a substantial amount of polynuclear aromatics and which is generally a waste product of a catalytic cracking refinery process. The sulfur-chlorinated cyclic oil is formed by reacting the oil with about 0.1% w. to about 10% w. of sulfuric acid, the amount of sulfuric acid being less than the maximum amount required to react completely with the oil. After removing the sludge formed by this reaction, the oil is reacted with a normally liquid, sulfur halide, after which any resulting precipitate and gaseous halides are separated to leave a stable and homogeneous oil which possesses anti-weld and extreme pressure properties when used alone or upon dilution as a cutting or lubricating oil, and which contains up to about 20% W. of total sulfur and up to about w. of total chlorine.

BACKGROUND OF THE INVENTION This invention generally relates to cutting and lubricating oils, and more particularly to a process of making sulfur-chlorinated cyclic oils having anti-weld properties. With the increasingly short supply of crude oil, it has become more important to fully utilize all of the products of a crude oil refining process. One major by-product of an oil refining process are polynuclear compounds which usually contain a variety of side chains. During the oil refinery cracking process, polynuclear compounds may be formed from the cyclization of parafiins, dehydrogenation of aromatics or by a variety of other reactions. These by-products, which are commonly called cyclic oils, exhibit little lubricating properties and are often discarded or marketed as weed killers, etc.

With the increased scarcity of raw crude oil causing increased prices for oil products, the use of inexpensive cyclic oils as a starting material for the manufacture of a cutting oil or cutting oil additive with anti-weld and extreme pressure properties is very desirable. Cutting oils used in the machining of steel and like metals require anti-weld properties to prevent the binding up of the machining metal with the work piece. An antiweld lubricant is especially required for the making of deep cuts in soft metal where the Work piece may approach its welding temperature. Ideally, a lubricating oil having anti-weld properties reacts with the tool and work surface just below the weld temperature to pre vent the two from welding together. Such anti-weld lubricating oils are usually made up of sulfur compounds which form an iron sulfide with the tool and work surface below the weld temperature to prevent these surfaces from welding together.

The effectiveness of a sulfur-containing anti-weld lubricating oil is often dependent upon the amount of sulfur which is available to react just below the weld tem perature. Generally, sulfurized fats, esters and waxes have tightly-bound sulfur atoms which will not readily react below the weld temperature unless also exposed to extreme pressure. Consequently, such materials as sulfur-chlorinated fats and esters find their use as extreme pressure additives rather than anti-weld additives in lubricating oils. These materials release little if any sulfur or chlorine below the weld temperature of soft metals. They possess, however, cooling and loadbearing properties to prevent the welding of hard metals at extreme pressures.

On the other hand, incorporation of loosely bound sulfur or halogen atoms into a cutting oil, so that the atoms are active at room temperature may result in corrosion of work pieces and tools. Also, free sulfur may result in instability of the oil itself. Thus, the ideal sulfurized cutting oil is one which is inactive under ambient conditions, but which exhibits anti-weld properties at a temperature below the welding temperature of the work piece, and extreme pressure properties for the machining of harder metals.

'In US. Pat. 3,309,315 assigned to the same assignee as the present invention, it was discovered that by selection of a mildly or incompletely acid treated naphthenic mineral oil, a concentration of sulfur useful to impart anti-weld properties could be introduced into the oil by reaction with a sulfur halide. However, it was heretofor believed that the cyclic oil refining by-products such as the products of a catalytic cracking process were such that further treatment would result in such sludge formation that the manufacture of a useful product would be uneconomical.

Although the reaction of a sulfur halide, such as sulfur monochloride, with substantially pure cyclic compounds such as naphthalene and anthracene derivatives are known, (U.S. Pat. 2,402,685) it was never thought that the sulfur-chlorination of the sludge forming cyclic by-products of a crude oil refinery process would yield a useful product. Generally, such a by-product contains a large amount of impurities including nitrogen, sulfur, and unsaturated olefinic compounds as well as long sidechains, which inhibit any reaction. It would appear uneconomical if not impossble to economically react these compounds further to form a useful product.

SUMMARY OF THE INVENTION A cracked oil, which is generally a by-product of an oil refining process and which contains substantial amounts of polynuclear aromatic compounds having a viscosity index below 0 and boiling between 350 and 800 F., is reacted with about 0.1% w. to about 10% w. of sulfuric acid, such amount of sulfuric acid being less than the maximum amount required to react completely with the oil but which will precipitate unwanted impurities. After sulfuric acid treatment, the oil may optionally be neutralized by treatment with a base, or adsorbant clay may be used to adsorb soluble acids. Preferably, however, the acid treated oil is not neutralized, but rather, directly reacted with a normally liquid sulfur halide which, after the resulting sludge and hydrogen halide are removed, forms a stable and homogeneous oil having anti-weld and extreme pressure properties, characterized by lack of olfensive odor, a clear, darkreddish color, and containing up to about 20% total sulfur and up to about 5% total chlorine.

PREFERRED EMBODIMENT One of the major by-products of a crude oil refining process is cyclic oils generally containing one to four ringed aromatic compounds, such compounds generally having substantially saturated side chains of less than ten carbon atoms. Such a by-product may also contain naphthenes, other saturated cyclic compounds, as well as olefins and saturated aliphatic compounds. These by-products, which have undergone cracking in the oil refining process are generally of little commercial use, since they will readily form a sludge upon any further reaction. Because of the large number of impurities contained in these byproducts, much of which will quickly react to form a sludge, it is generally unfeasible to further treat them to make a useful product.

By separating out the fraction of such cyclic compounds, boiling within a range of 3.50 to 800 F. and preferably between 400 and 700 F., a light cyclic oil, containing as a major ingredient two and three membered ringed compounds and generally having a viscosity index below is obtained.

This light cyclic oil having the polynuclear aromatics is then reacted with up to about w. of sulfuric acid, such amount of acid being sufficient to separate out unwanted impurities which will form a sludge upon treatment with sulfur monochloride. Such impurities as nitrogen, oxygen and sulfur compounds are precipitated, yet the polynuclear aromatics are left unreacted. Additionally, soluble sulfonic acid derivatives, commonly called red acids, are formed by the sulfuric acid treatment. The insoluble reaction products (green acids) are first removed, after which optionally, the soluble red acids may be neutralized or removed. We have found that neutralization of these red acids is preferably not required for the sulfurmonochloride reaction.

After the sulfuric acid treatment, and the optional neutralization step, the oil is treated with a liquid sulfur halide, such as S Cl so as to produce a useful anti-weld cutting oil. Up to about 32% w. S Cl may be reacted with the acid treated cyclic oil. However, addition of S Cl must be done in stages, since the initial reaction is rapid. We have found that the reaction generally requires no catalyst, especially if the cyclic oil is in the unneutralized state. It is believed that the unneutralized soluble sulfonic acids serve as a catalyst for the S Cl reaction and may aid in retaining more C1 in the final product.

Although the reaction is not fully understood, it is believed that the S Cl when reacted in the presence of sulfonic acids at preferably ambient temperatures, forms a sulfur chlorinated oil of the general formula RSCl and R-SS--Cl where R contains two and three ringed aromatic compounds. This is very different from other sulfur-chlorinated products such as fats or waxes which release sulfur or chlorine only under extreme pressure. The extreme pressure is necessary for these products since the sulfur and chlorine are tightly bound to the carbon backbone by, for example, the saturation of double bonds. However, since the cyclic compound of this invention also may contain substantial amounts of unsaturated compounds which will undergo sulfur-chlorination to give tightly bound sulfur and chlorine atoms, the product of the present invention may be used as both an anti-weld and extreme pressure additive.

Upon the addition of S Cl a substantial increase in viscosity and darkening of color is apparent. In fact, at the completion of the S 01 reaction, the oil is so dark, so viscous and so full of sludge as to appear unsuitable for any application. However, by blowing air at about 150 F. through this product for a suflicient time to remove all gaseous halides, evidenced by the lack of offensive odor, and then by removing any precipitate, a lubricating oil having a clear, reddish color with a viscosity of ranging from 90 to 200 SSU at 100 F. and useful as a cutting oil by itself or upon dilution is obtained.

The invention will be better understood by reference to the specific examples, which are illustrative of the invention, but not intended to be limited thereto. Specifically, although in the specific examples sulfuric acid is used to remove and react with compounds which form sludge upon exposure to S Cl other means to remove such impurities may be utilized without departing from the spirit and scope of the invention.

4 EXAMPLE I Mobil MZY 409 cyclic oil from the Mobil Oil Co., having a distillation range between 400 and 700 F. is agitated with 4% w. concentrated sulfuric acid for minutes, allowed to settle for four hours, after which the precipitate is separated.

EXAMPLE H The product of Example I, or a commercially available acid treated cyclic oil such as Mobil MZY 413 from the Mobil Oil Co. is further treated with S CI To 860 gms. of unneutralized MZY 413 cyclic sour oil is added 82 gms. (9.5%) of S2012 at ambient temperatures with mixing by air blowing. The reaction is carried out in an iron kettle which may serve to catalyze the reaction.

Additional S Cl is added in intervals so as not to cause a rise in temperature of greater than 'F. After allowing the first S Cl to react for one half hour, 60 gms. (7%) of S Cl was added, and allowed to react for 15 minutes before a final addition of 73 gms. (8.5%) of S Cl was made. Air blowing was continued for an hour and the reaction vessel was allowed to stand overnight. The reaction product at this point was viscous, exceedingly dark and full of sludge so as to appear unsuitable for any lubricating oil application. Air was then blown through the oil for about 16 hours at 170 F. until no chlorine odor was present. This air blowing step resulted in the dissolution of much of the sludge, after which the remaining sludge was removed. The resulting product had the following properties:

Gravity API, 60 F 5.0.

Specific gravity, 60 F. 1.0366. Pounds per gallon 8.36. Viscosity SSU at 100 F. 150.

Pour point Less than 0' F. Flash COC 245.

Total sulfur (ASTM D129) 11.5.

Total chlorine (D808) 2.01.

Copper corrosion at 72 F Minor.

Although the sulfur activity of this product at room temperature as indicated by the copper corrosion test does not appear to indicate anti-weld properties, the oil has demonstrated excellent anti-weld properties in the field. It may be blended with pale oils, or may be used by itself if the proper lubricating fraction is selected. {it has also demonstrated extreme pressure properties in the cutting of hard metals such as stainless steel or titanium.

As a cutting oil, 25% w. of the oil of Example I was blended with 75% pale mineral oil. When used in threading stainless steel pipe, no gouging was evidenced. Applications for the oil of this invention which possesses both anti-weld and extreme pressure properties include use as a cutting oil, alone or as an additive, for broaching, drilling and machining operations as well as for use as a gear oil.

What is claimed is:

1. A process which comprises reacting a normally liquid sulfur halide with an oil obtained from the cracking of petroleum said oil, containing as a major ingredient polynuclear aromatics and boiling between 350 and 800 F. and having separated therefrom by sulfuric acid treatment the majority of impurities which form a permanent sludge when reacted with a normally liquid sulfur halide, and separating any resulting precipitate and hydrogen halide formed therefrom to leave a stable and homogeneous cyclic oil having anti-weld properties, characterized by lack of offensive odor and containing up to about 20% total sulfur and up to about 5% total chlorine.

2. The process which comprises reacting an oil obtained from the cracking of petroleum and containing as a major ingredient polynuclear aromatics having a viscosity index below 0 and boiling between 350 and 800 F. with about 0.1% w. to about 10% w. of sulfuric acid, such amount of sulfuric acid being sufficient to remove the majority of impurities Which form a permanent sludge when reacted with a normally liquid sulfur halide but less than the amount required to react completely with the oil, removing the sludge formed thereby, reacting it with a normally liquid sulfur halide and separating the resulting precipitate and hydrogen halide formed therefrom to leave a stable and homogeneous oil having anti-weld properties, characterized by lack of offensive odor and containing up to about 20% total sulfur and up to about 5% total chlorine.

3. The process of claim 2 wherein the starting oil boils betwen 400 and 700 F.

4. The process of claim 2 wherein said sulfur halide is substantially sulfur monochloride.

5. The process of claim 4 wherein the sulfuric acid is about 0.5% w. to about 5% w. and said sulfur monochloride is added in fractional amounts up to about 32% w. during an extended period of time up to about hours, at substantially ambient temperatures, the reaction proceeding until no odor of sulfur halide or hydrogen halide is evident upon heating to about 200 F.

6. The process of claim 5 wherein the reaction proceeds for about 48 hours.

7. The process which comprises reacting an oil obtained from the cracking of petroleum, said oil containing as its major ingredient cyclic compounds having more than one ring member boiling betwen 350 and 800 F. and having a viscosity index of less than 0 with about 0.1% w. to about 10% W. of sulfuric acid, such amount of sulfuric acid being sufiicient to remove the majority of impurities which form a permanent sludge when reacted with a normally liquid sulfur halide but less than the amount required to react completely with the oil, removing the sludge formed thereby, reacting it with a normally liquid sulfur halide and separating the resulting precipitate and hydrogen halide formed therefrom to leave a stable and homogeneous oil having anti-weld properties and characterized by lack of offensive odor and containing up to about total sulfur and up to about 5% total chlorine in oil soluble organic compounds which may be used as cutting oil by itself or upon dilution.

8. The process of claim 7 wherein the starting oil boils between 400 and 700 F.

9. The process of claim 7 wherein the final oil has a viscosity between 90 and 220 SSU.

10. A cutting fluid containing homogeneously and stably dispersed therein an anti-Weld quantity of the reaction product between a normally liquid sulfur halide and a cyclic mineral oil, said reaction product being formed by reacting an oil obtained from a petroleum cracking process boiling between 350 and 800 F. having a viscosity index below 0 and containing a major ingredient cyclic compound having more than one ring member with about 0.1% w. to about 10% W. of sulfuric acid, such amount of sulfuric acid being suflicient to remove the majority of impurities which form a permanent sludge when reacted with a normally liquid sulfur halide but less than the maximum amount required to react com-. pletely with the oil, removing the sludge formed thereby, reacting it with a normally liquid, sulfur halide and separating the resulting precipitate and hydrogen halide formed therefrom to leave a stable and homogeneous oil having anti-weld and extreme pressure properties and characterized by lack of offensive odor and containing up to about 20% total sulfur and up to about 5% total chlorine.

11. The cutting fluid of claim 10 wherein the sulfur halide is essentially sulfur monochloride.

References Cited UNITED STATES PATENTS 3,309,315 3/1967 Hanna et a1 252 42.4 2,112,677 3/1938 Muscat 252- 2,402,685 6/1946 Signaigo 260139 X 2,628,228 2/1953 King et al. 252-139 X 2,859,172 11/1958 Reymond 208-96X FOREIGN PATENTS 507,385 6/1939 Great Britain 252-45 WARREN H. CANNON, Primary Examiner US. Cl. X.R. 25245; 260139

Claims (1)

1. A PROCESS WHICH COMPRISES REACTING A NORMALLY LIQUID SULFUR HALIDE WITH AN OIL OBTAINED FROM THE CRACKING OF PETROLEUM SAID OIL, CONTAINING AS A MAJOR INGREDIENT POLYNUCLEAR AROMATICS AND BOILING BETWEEN 350 AND 800* F. AND HAVING SEPARATED THEREFROM BY SULFURIC ACID TREATMENT THE MAJORITY OF IMPURITIES WHICH FORM A PERMANENT SLUDGE WHEN REACTED WITH A NORMALLY LIQUID SULFUR HALIDE, AND SEPARATING ANY RESULTING PRECIPITATE AND HYDROGEN HALIDE FORMED THEREFROM TO LEAVE A STABLE AND HOMOGENEOUS CYCLIC OIL HAVING ANTI-WELD PROPERTIES, CHARACTERIZED BY LACK OF OFFENSIVE ODOR AND CONTAINING UP TO ABOUT 20% TOTAL SULFUR AND UP TO ABOUT 5% TOTAL CHLORINE.