US2197712A - Mineral oil compositions and processes of preparing the same - Google Patents

Description

Patented Apr. 16, 1940 PATENT OFFICE MINERAL OIL COMPOSITIONS AND PROG- ESSES OF PREPARING THE SAME Anderson W. Balaton and Everett J. Hofiman,

Chicago, 111., assignors to Armour and Company, Chicago, 111., a corporation of Illinois No Drawing. Application October 14, 1938 Serial No. 235,094

7 Claims.

This invention relates to mineral oil compositions and processes of preparing the same, and it comprises mineral oil compositions, such as lubricating oils and greases, containing small amounts of an acylated and polymerized coumarone, it further comprises such mineral oil com-positions containing small amounts of the product of acylating coumarone, or one of its polymers, in the presence of a metallic chloride 10 acylatin'g catalyst, hydrolyzing the intermediate metallic chloride complex and recovering the catalyst-free acylated and polymerized coumarone.

For many uses in the art lubricating oil com- 16 positions having low pour points must be used.

The pour point of an oil is in part directly related.

to the amount of parafiin wax in the oil and it is customary to dewax the oil both for the recovery of usable pa'raflin and for lowering the 20 pour points of the oil. Even after drastic dewaxing operations the final lubricating oil does not always have as low a pour point as the art desires. Paraffin wax itself, however, has lubricating characteristics, and prior workers have 25 sought to keep some of the wax in the oil by so modifying the pour point of the oil that in spite of its wax content the oil can be used for lubricating at low temperatures. This has been accomplished in recent years by adding to the 30 oil substances to which the name pour point depressors has been given. Quite a few substances for this purpose have been discovered. Theoretically it is assumed that a pour point depressor inhibits crystallization of the paraflin 35 wax in the oil and thus prevents the oil, when subjected to low temperatures, from forming a. kind of sludge or slush of relatively large wax crystals occupying the entire volume of the oil and occluding liquid oil within the network of 40 crystals.

At the present time condensation products between chlorinated paraflins and aromatics are used to a considerable extent as pour point depressors. Products of this nature are much less effective in their actions than compounds described in this invention. In addition they contribute nothing to the oiliness of the-lubricant to which they are added, which is markedly different from our products.

In all instances the amount of pour point depressor added is relatively small. The quantities generally average a fraction of a percent based on the quantity of oil.

We have now discovered a class of materials which function particularly well as pour poin depressors, and which have the added advantage that they impart oiliness to the oil. The substances which we use can be generically defined as acylated coumarones wherein the acyl group contains at least twelve carbon atoms. -These acylated coumarones are new materials in themselves and are the subject matter of the Ralston, Vander Wal and Segebrecht application Serial No. 228, 261, filed September 2, 1938. These compounds are prepared, broadly speaking, by reacting coumarone, or one of its polymers, with a fatty acid chloride having at least twelve carbon atoms in the presence of an acylating catalyst, such as aluminum-chloride. This reactionresults in the formation of an intermediate complex containing the catalyst which is thereafter hydrolyzed to free it of catalyst, and the final product recovered. Thus the preparation of these acylated coumarones follows closely the acylation of other aromatic hydrocarbons by the Friedel- Crafts synthesis. But during the acylation of the coumarone the coumarone polymerizes. Or it is possible that the coumarone is first acylated and thereafter the acyl derivative polymerizes. In any event, the final product is an acylated and polymerized coumarone. Or, to put it more definitely, it is a polymerized coumarone containing acyl groups having twelve or more carbon atoms. v

In the preparation of these pour point depressors any fatty acid chloride having twelve or more carbon atoms can be used. These can be either saturated or unsaturated, or they can be fatty acid chlorides made from fatty acids prepared by the oxidation of paraffin wax or other hydrocarbons yielding fatty acids on oxidation. Mixtures of two or more different fatty acid chlorides can be used as the ac'ylating agent. This gives us final products of mixed character and very complex constitution. 'Indeed the pour point depressor effect of our products may possibly be due to the complex nature of them. As fatty acid chlorides we can use lauryl, myristyl, palmityl, stearyl, oleyl, linoleyl and linolenyl chlorides, these being the more usual ones.

In broad aspects, the fatty acid chloride is added to a suspension of the acylating catalyst, such as aluminum chloride, in an inert solvent, and to this mixture coumarone dissolved in an inert solvent is added. The proportions of fatty acid chloride to coumarone canvary over wide limits as wehave found by experiment. This probably means that so long as the coumarone polymer contains at least one acyl group the product has pour point depressor characteristics.

But more than one acyl group can be present in the final product.

We shall now give an example of how our pour 4 point depressors are made from fatty acid chlorides of at least twelve carbon atoms and coumarones.

Eaample ture is then maintained at 45 C. to 50 C. for V The reaction mixture comprisabout ,one hour. ing an aluminum chloride complex is then decomposed on ice and the solvents removed by steam distillation. The product is dissolved in ether and the ether solution dried with anhydrous sodium sulfate. The ether is then removed by distillation under a vacuum.

In precisely the same manner other acylated coumarones are prepared as more fully disclosed in the aforesaid .application.

The final product is semi-solid and plastic, and resinous in character. It dissolves readily in mineral oils in proportions used for pour point depressing.

We shall now indicate by way of example how our products function when added to lubricating oils.

In the following examples the oils designated as 1, 2 and 3 are three different kinds of lubricating oils in common commercial use. The examples also indicate the pour point of the original oil and the pour point of the oil after the addition of our pour point depressors.

Example 1 I saybolt Pour point, F. 011 viscosity at Original Treated Example 2 0.5% of a product prepared from 12 parts of coumarone and 30 parts of oleyl chloride is added giving the following results:

Pour point, F.

Oil

Original Treated Example 3 0.5% of a product prepared from 20 parts coumarone and 30 parts .of stearyl chloride is added to the oils with the following results:

aybolt P 0111' P nt. F. Oil viscosity at 100 al Treated Second Example 4 0.5% of a product prepared from 30 parts of coumarone and 20 parts of stearyl chloride is added to the oils with the following results:

saybolt Pour point, F. Oil viscosity F Original Treated Example 5 0.5% of a product prepared from 30 parts of coumarone and 30 parts of stearyl chloride is added to the oils with the following results:

0.5% of a product prepared from 11.8 parts of coumarone and 30 parts of linolenyl chlorideis added tothe oils with the following results:

'saybo Pout point, F. Oil viscogltyat Original Treated Seconds I Thus from the above examples it is apparent that our pour point depressors aremarkedlyefi'ective for the purpose intended, a pour point lowering of as much as 50 F. being obtained. Our pour point depressors are especially effective on oils having rather high pour points, thus indicating the marked ability of our compounds to prevent crystallization of the wax.

Similar results are obtained when other fatty acid chlorides having twelve or more carbon atoms are used. The amount of pour point depressor can vary over wide limits. Noticeable improvement in pour point lowering is obtained when only 0.1% of our products is added. Larger amounts, up to 2% or 3% can also be added but much greater amounts, such as 10% or 15% are not necessary in order to obtain a. substantial pour point lowering.

In addition 'to the property of lowering the pour point of the mineral oils these products also decrease the heat generated during running friction. The oils were tested in an apparatus described by Ralston, Hoffman and Stephens, found in National Petroleum News, dated November 3, 1937. The following table shows the temperature rises after one hour for various treated and untreated oils. In the case of the treated oils 0.5% of the product described and used in Example 1 is added.

0.5% of the product lowered the pour point of the gas oil from 65F. to F.

In the appended claims we use the language a coumarone" to include the coumarone dimers, trimers or tetramers as well as coumarone itself since the coumarone thereof is the essential polymerizing component.

Although we have referred more particularly to the use of our acylated coumarone materials with lubricating oils it is apparent that they can also be added to lubricating greases where it is desirable to reduce the heat of friction or to prevent the grease Irom assuming a relatively hard, non-flowing state when subjected to a cold environment. When preparing such greases we can first dissolve the pour point depressor in the lubricating oil and then make a lubricating grease therefrom in the usual way.

Having thus described our invention, what we claim is:

1. A mineral oil containing, as a pour point depressor, an acylated coumarone, the acyl group having at least twelve carbon atoms.

2. A mineral oil contain g. as, a pour point depressor, a stearylated coumarone.

3. A mineral oil containing, as a pour point depressor, an acylated coumarone polymer wherein the acyl group contains at least twelve carbon atoms.

4. A mineral oil containing, as a pour point depressor, a stearylated coumarone polymer.

5. A mineral oil containing, as a pour point depressor, the product obtained by reacting coumarone with a fatty acid chloride having at least twelve carbon atoms in the presence of an acylating catalyst, and recovering a catalyst-free product.

6. A mineral oil containing, as a pour point depressor, the product of reacting a coumarone with stearyl chloride in the presence of an acylating catalyst and recovering a catalyst-free product.

7. The process of depressing the pour point of a mineral oil which comprises adding to the oil the products resulting from reacting a. coumarone with a fatty acid chloride having at least twelve carbon atoms in the presence of an acylating catalyst and recovering a catalyst-free product.

ANDERSON W. RALSTON. EVERETT J. HOFFMAN.