US2739124A

US2739124A - High metal content complex salts of sulfonic acids and mineral oil compositions thereof

Info

Publication number: US2739124A
Application number: US307922A
Authority: US
Inventors: Ferdinand P Otto; Robert H Williams
Original assignee: Socony Mobil Oil Co Inc
Current assignee: ExxonMobil Oil Corp
Priority date: 1952-09-04
Filing date: 1952-09-04
Publication date: 1956-03-20
Anticipated expiration: 1973-03-20

Description

2,739,124 Patented Mar. 20, 1956 HIGH IWETAL CGNTENT COMPLEX SALTS OF ULFONIC ACIDS AND MINERAL OIL COM PUSITIGNS Ti-EREOF Application September 4, 1952, Serial No. 307,922

22 Claims. (Cl. 252-33) No Drawing.

This invention relates to improved lubricating oil compositions for use in internal combustion engines. More particularly, it relates to a new class of detergent additives for such lubricating oils and to a method for their preparation.

It is well known that lubricating oils tend to deteriorate under the conditions of use in present day diesel and automotive engines with attendant formation of sludge, lacquer and resinous materials which adhere to the engine parts, particularly the piston ring grooves and skirts, thereby lowering the operating eficiency of the engine. To counteract the formation of these deposits in the engine, certain chemical additives have been found which when added to lubricating oils have the ability to keep the deposit-forming materials suspended in the oil so that the engine is kept clean and in efficient operating condition for extended periods of time. These addition agents are known in the art as detergents or dispersants. Metal organic compounds are particularly useful in this respect. These metal organic compounds are considered to be effective on the basis of their metal contents coupled with their solubility in the oil. Generally, it has been found that the oil-soluble metal organic compounds having the greater percentages of metal provide the better detergents. On this basis, it has been sought to provide detergent compounds having the highest possible metal contents. Metal sulfonates, such as petroleumsulfonates and wax-aryl sulfonates, have been found to be particularly eflective detergents for mineral lubricating oils. The present invention is concerned with the provision of a new class of metal sulfonates, hereinafter called complex metal sulfonates, which have exceptionally high metal contents and which are highly superior oil detergents. The metal contents of these new complex metal detergent salts range from upwards of 50 to about 100 per cent higher than the metal contents of normal metal sulfonate salts, i. e., salts havingmetal contents equivalent to the acid-hydrogen contents of the respective sulfonic acids from which they are derived.

It is, therefore, the object of this invention to provide a new class of complex metal sulfonate salts having exceptionally high metal contents. It is a further object to provide oil compositions containing relatively small amounts of these new complex metal salts, which compositions are of high detergent character. Other and further objects will become apparent from the following detailed description of the invention.

Broadly, the complex metal salts of this invention are prepared by a method which comprises (1) intimately contacting an oil, or hydrocarbon, solution of a sulfonic acid, in the presence of water, with (a) at least about 1.4 equivalents of a metal hydroxide, (b) at least about 0.3 equivalent of a metal chloride and (c) at least about 0.3 equivalent of a metal carboxylate, said equivalents being based on the equivalents of acid-hydrogen in the sulfonic acid solution, (2) substantially completely dehydrating the reaction mixture formed in step 1 to produce the complex metal salt product and (3) filtering ofi insoluble material.

A satisfactory procedure for carrying out the invention is as follows: ,An aqueous slurry of the three metal-containing reagents is first prepared. This slurry is then intimately contacted with the sulfonic acid at a temperature of from about 25 C. up to about C. A diluent oil is required in the case of the synthetic type sulfonic acids in order to facilitate the reaction and the handling and filtration of the complex salt product. The synthetic sulfonic acids are, therefore, first dissolved in oil to form a solution of, say, from about 20 to about 60 per cent of the acid in the oil, this solution being contacted with the reagent slurry. The petroleum sulfonic acids are, of course, already diluted with oil, generally being pres,- ent therein in amounts of from about 20 to about 60 per cent, and these acids, or sour oils, ordinarily require no addition of diluent oil for the purpose of the reaction with the metal-containing reagents. The contacting of the sulfonic acid (solution) with the reagent slurry is accomplished by slow addition of the slurry to the heated acid with constant stirring of the mixture thus formed. When the addition is completed, the mixture is dehydrated by raising the temperature up to about C. and maintaining this temperature until the dehydration is complete. The dehydrated product is then filtered to remove excess salt reagent. The product thus obtained is an oil solution which usually contains from about 20 to about 60-75 per cent, more or less, of the complex salt. It will be appreciated that in the case of the synthetic type sulfonic acids other hydrocarbon solvents may be used for the reaction besides mineral oil, such as a light naphtha, xylene, toluene or the like; however, use of a petroleum .oil is preferred since it need not be removed after the reaction, the oil solution thus obtained being directly blendable with the lubricating oil desired to be fortified with the complex salt product.

Although the aforedescribed procedure is the one generally used, the manner and time of bringing the sulfonic acid solution and the metal compound reagents together may be varied without afiecting the reaction, or yield of complex salt product obtained. Thus, the sulfonic acid solution may be added to the reagent slurry, or the sulfonic acid can .be first reacted with themetal hydroxide and then reacted with an aqueous solution of the metal chloride and metal tcarboxylate. Also, the normal metal sulfonate .may be reacted with a slurry of all three rea'ctants, the slurry containing equivalent amounts of metal hydroxide, metal chloride and metal carboxylate. These and other modifications of the procedure of the invention will .be obvious to those skilled in the art. In any case, it is essential to the process of our invention that a good dispersion .of the reactants be obtained, that water be present and that dehydrationof the reaction mixture be carried to substantial completion. As already indicated, it is also necessary that certain minimum amounts of the metal hydroxide, metal chloride and metal carboxylate reagents be used in the reaction in order to provide the complex salts of the invention. The metal chloride and the metal .carboxylate may be supplied in the form of a mixture (slurry) of the metal hydroxide with hydrochloric and carboxylic acids. When the three reagents are supplied in the form of metal salts, at least 1.4 equivalents of metal hydroxide, 0.3 equivalent of metal chloride and 0.3 equivalent of metal carboxylate are requi'red per equivalent of acid-hydrogen in the sulfonic acid. However, where the hydrochloric acid and .carboxylic acid are supplied as such to the reaction, the amount of metal hydroxide is increased to 2.0 equivalents in. order .to provide the necessary equivalents of metal in he reaction.

The necessity for the presence of water is illustrated by the fact that when dried calcium chloride and calcium acetate, for example, were added to an oil solution of normal calcium sulfonate and heated, subsequent analysis of the filtered oil showed no increase in the calcium content thereof. In general, it may be said than an amount of water equal to from about to 50 per cent by weight of the sulfonic acid solution charged to the reaction has been found to be satisfactory. The maximum amount of water used is limited only by practical considerations, such as the amount of reactants used and the time required for dehydration.

The necessity for dehydrating the reaction mixture is illustrated by the fact that if the reaction mixture is not substantially completely dehydrated, but only refluxed for a few hours, the oil phase, when separated from the aqueous phase, shows a metal content equal only to the normal metal sulfonate. The dehydration step has been conducted under various conditions and there is no definite limitation on the method of dehydration, except for practical considerations. Generally, the dehydration is accomplished by heating at moderately elevated temperatures, i. e., from 50 C. to 120 C., for several hours. Although higher reaction temperatures may be used, they are unnecessary. Thus, in those instances where the dehydration temperature reached as high as 150 C., the metal contents of the products obtained were only slightly higher than where the temperature remained below about 100 C. The dehydration may be facilitated by blowing a gas, such as air or nitrogen, through the heated reaction mixture. Generally, it is preferable to filter the product at temperatures in the neighborhood of 100 C., since this temperature is high enough to keep the product quite fluid.

Due to the intricate nature of the complex metal salts thus produced, no chemical formula can be ascribed to them at this time. Neither is the manner of their formation precisely known. However, without intending to limit our invention, we believe that our complex salts are formed via a two-step process in which the normal sulfonate salt is first formed by reaction with the metal hydroxide, the normal salt then being reacted further with the metal hydroxide-metal chloride-metal carboxylate reagent during dehydration to yield the final product. The formation of the complex salt during dehydration is postulated on the basis of certain experimental observations. Thus, although an oil solution of complex metal sulfonate is obtained by interaction of a sulfonic acid with an aqueous slurry of metal hydroxide, metal chloride and metal acetate by substantially completely dehydrating the reaction mixture (i. e., removal of at least about 90 per cent of the water), if the oil phase is separated-before such dehydration, the metal content corresponds only to that of a normal metal sulfonate. Also, indications of the formation of complexes between the metal compound reagents during dehydration are had from X-ray diffraction examination of the solid material obtained on evaporating an aqueous solution of (a) calcium chloride and calcium acetate and (b) calcium hydroxide, calcium chloride and calcium acetate. Such analyses show no patterns which can be attributed to either calcium chloride or calcium acetate, thus indicating the formation of different compounds. Furthermore, it has been found that more metal can be incorporated into the complex salt product by using a mixture of metal chloride and metal acetate along With the metal hydroxide than by using an equivalent amount of either salt alone. This is believed to be due to the formation of a chlorideacetate complex. Finally, since the presence of an appreciate amount of water is necessary in order to form our complex salts, ionization is apparently an essential factor in their formation. 7

We are aware that certain complex metal sulfonate salts have been shown in the prior art. However, the complex salts herein disclosed are different from those heretofore described. Thus, Zimmer et al., No. 2,467,176, show the formation of complex metal sulfonate salt detergents by the reaction of a normal sulfonate salt with either a metal chloride or a metal acetate and a metal hydroxide. Our

process, however, involves the reaction of three, rather than two, reagent salts with the sulfonic acid, viz., a metal hydroxide, a metal chloride and a metal carboxylate. We have found that by our process much greater amounts of metal can be incorporated into the complex salts than by the method of Zimmer et al. Thus, the highest amount of metal shown by Zimmer et al. is 43 per cent, whereas our complex salts contain from at least 50 per cent to 90 per cent metal. Our products are, therefore, of a distinct nature from those of Zimmer et al. Furthermore, the manner of incorporation of excess metal into the sulfonate salts by our method is apparently different from that of Zimmer et al. This is indicated by analytical and X-ray diifraction studies of the solids formed upon evaporation of water slurries composed of the reagents used in the two processes. Thus, when a water slurry consisting of calcium chloride and calcium hydroxide is dehydrated (Zimmer et al.), the analytical and X-ray data indicate the formation of a calcium hydroxide-calcium chloride complex, whereas in the case of a Water slurry containing calcium hydroxide, calcium chloride and calcium acetate, it is found that the solid consists predominantly of a calcium chloride-calcium acetate cornplex along with a minor amount of a calcium hydroxidecalcium chloride-calcium acetate triple component complex, without any calcium chloride-calcium hydroxide complex being present.

In the grease art, several patents, viz., Zimmer et al., No. 2,444,790, and OHalloran, Nos. 2,553,422 and 2,563,814, disclose complex sulfonate salts as gelling agents. These salts are formed by reaction of normal sulfonate salts with low molecular weight acid salts, such as metal carboxylates. Our complex salts, however, are distinguished from the complex salts of these patents by virtue of the fact that these latter salts are oil-insoluble and provide grease-like structures in the oil, whereas our complex salts are oil-soluble. Since the composition of our complex salts is different from that of the complex salts of the prior art, they are claimed herein as new compositions of matter.

I The metal constituents of the metal hydroxide, metal chloride and metal carboxylate reactants used in the prepprepared and tested complex salts containing two and three metal constituents and have found them to be highly effective detergents as shown in the examples presented hereinafter. Up to the present time, our Work has extended only tothe metal salts of those metals falling within group I and group II of the periodic table. However, it seems probable that reagent salts of other metals will also be found to be suitable for the invention. We have found that the alkaline earth complex metal salts, particularly the calcium salts and the mixed calciumbarium salts, provide outstanding detergents for lubricating oils.

The carboxylic acids, or salts thereof, suitable for the preparation of our complex metal salts are the aliphatic monocarboxylic acids having from 1 up to about 20 carbon atoms in the aliphatic portion thereof. The acid used may be either saturated or unsaturated. it may also contain certain substituent groups, such as phenyl, hydroxy, halogen, amino or mercapto groups. As noulimiting examples of such acids there may be mentioned formic acid, acetic acid, chloroacetic acid, phenyl'acetic acid, hydroxy acetic acid, glycine, thioglycollic acid, acrylic acid, propionic acid, butyric acid, butenic acid, valeric acid, heptylic acid, caproic acid, lauric acid, myristic acid, palmitic acid, oleic acid, stearic acid and the like. The lower molecular weight acids, such as formic and acetic acids, are preferred however, since they provide complex salts having the higher proportions of metal per mol of complex salt.

As aforesaid, the sulfonic acids suitable for use in this invention include oil-soluble petroleum sulfonic acids and synthetic alkaryl sulfonic acids. The sulfonic acids having higher molecular weights, i. e., from about 300 to about 800, are particularly preferred. These sulfonic acids may be produced by sulfonation of petroleum stocks or synthetic alkyl aromatic compounds, such as alkyl-substituted benzenes or naphthalenes, wherein the alkyl groups attached to the aromatic ring contain at least about 8 carbon atoms, the wax-substituted benzenes and naphthalenes being particularly preferred. The petroleum sulfonic acids, also known as sour oils, are those obtained in the treatment of petroleum oils, particularly refined, or semi-refined oils, with concentrated or fuming sulfuric acid, and which remain in the oil after settling out of sludge. These sulfonic acids may be represented by the general formula (1K)" SOJH where R is one or more alkyl, alkaryl or aralkyl groups and the aromatic nucleus is a single or condensed ring or partially hydrogenated ring. Example 1 illustrates the preparation of a typical petroleum sulfonic acid. The oil used was a furfural-refined, Mid-Continent heavy distil- Preparation of petroleum sulfonic acid The charge oil was treated with 30 per cent by weight of 103 to 104 per cent sulfuric acid by adding the acid gradually to the oil over a period of about 2 hours, the mixture being agitated by airblowing and the temperature being maintained at 100 to 120 F. during the addition. Following this, the product was treated with quench water (about 6 per cent by weight of charge oil) in order to dilute the sulfuric acid and facilitate separation of acid and sludge from the sulfonic acid (sour oil). The water was added over a period of about -30 minutes, so that the temperature of the mixture was maintained at 115160 F. The crude sour oil was allowed to settle for about 18 hours, after which sludge and spent acid were withdrawn and the product blown with air at about 160 F. to remove occluded S02. This was followed by a final settling period of 50 hours at 160 F. to insure as complete removal as possible of spent acid and sludge. The yield of sour oil was approximately 97 per cent by weight of the oil charged. The total N. N. (neutralization number) of the product was 24.1 and the true N. N. 19.6. The total N. N. designates the combined acidity of the sulfonic acid and residual sulfuric acid in the sour oil while the true N. N. designates the acidity due to the sulfonic acid content of the sour oil alone.

Preparation of calcium chloride-acetate-sulfonate complex The sulfonic acid, prepared as above described, was

utilized to prepare a calcium chloride-acetate-sulfonate complex salt, as set forth in the following example.

EXAMPLE 2 Materials: I

400 grams of sour oil (Total N. N.=24.1, True N. N.=19.6) 3.2 grams of acetic acid (glacial) (0.3 equivalents based on total N. N. of sour oil) 3.8 grams of Dowfiake (77 per cent CaClz, 0.3

equivalents based on total N. N. of sour oil) 11.1 grams of grease makers lime (96 per cent Ca(OH)z, 1.68 equivalents) 100 cc. of H20 20 grams of Hyflo filter-aid Procedure.The calcium reagent was made by adding the acetic acid to a slurry prepared by dissolving the calcium chloride in a portion of the water and adding this solution to a slurry of the lime in the major portion of the water. It is advisable to retain about 20 cc. of water for washing to insure essentially complete transfer of the reagents from the vessel to the reaction mixture. The sour oil was placed in a l-liter, four-necked, round-bottorned ilask equipped with a mechanical stirrer, thermometer, air inlet tube, and a Dean-Stark water takeoff fitted with a reflux condenser. The sour oil was heated with stirring and with a moderate stream of air passing through it to approximately 75 C. The reagent slurry was then added slowly to the sour oil over a one-hour period from a dropping funnel. The slurry was stirred from time to time to assure homogeneity. When the addition was complete, more heat was applied and the water removed by means of the Dean-Stark take-off. The removal of the water took about 1 /2 hours with the temperature regulated so as not to exceed about 100 C. To insure dryness, dehydration was continued for another hour after the contents of the reaction vessel appeared bright and dry. Twelve grams of Hyfio (a diatomaceous earth filter-aid) were stirred into the product which was then filtered through a filter paper packed with Hyflo in a heated Biichner funnel. Three hundred seventyfive grams of product, a brownish-red oil, was obtained.

Analysis of product:

Percent calcium=1.25 (79 per cent in excess of a normal salt) Percent sulfur=l.27 Percent chlorine=0.16 K. V. 210, F.=21.l4 Potentiometric base No.=12.0

EXAMPLES 3-l2 As stated hereinbefore, we have found that the use of about 1.4 equivalents of metal hydroxide, about 0.3 equivalent of calcium chloride and about 0.3 equivalent of calcium carboxylate provide the best results in the preparation of our complex metal salts, these amounts being based on the acid-hydrogen value of the crude sulfonic acid (i. e., the total N. N.). It is to be understood, however, that these proportions may vary somewhat depending upon the residual sulfuric acid content of the particular sour oil or synthetic sulfonic acid used. This sulfuric acid content may vary in amount from about several per cent to 20-30 per cent of the total acid content in different sour oils and for the obtainment of optimum results the metal chloride and acetate reagents can be varied proportionately, i. e., they may be decreased with an increase in the sulfuric acid value and vice versa. Examples 4-12 illustrate the effect of varying the amounts of calcium hydroxide, calcium chloride and calcium acetate used on the metal contents of the complex salt products. The sulfonic acid utilized in these examples was that prepared in Example 1 and the method of preparing the complex salts was that of Example 2. The results are summarized in Table I.

8 an increase in, the amount of the magnesium acetate reagent up to 0.9 equivalent providesa complex salt product having exceptionally high metal. content. Also, as aforesaid, some variation in the amount of metal salt reagent must be permitted depending upon the residual sulfuric acid content of the particular sulfonic acid utilized. The amounts of the reagent salts designated herein, therefore, actually represent about the least amounts which TABLE I.-PREPARATION F COMPLEX CHLORIDE-ACETATE-CALClIiM summers Reagents Employed For 4%0 (1111231111 Sglignc Ae1d--Tota1 N. N.=24.1; Analysis of Product Example Number Lime C201: 3 OHaCQOH Ca(OAc)z ce t Potentm Perceent Excess P81861113 T meltge Perzent Equiv- Equiv- Equiv- Equiv- C8 1 a 358 Grams alents Grams alents G1 ems a1 ems Grams alems No.

9. 8 1. 2. 5 0. 2 2. 1 0. 2 0. 99 41 0. 24 6. 7 1. 19 11.1 1. 7 3. 8 0. 3 3. 2 0. 3 1.25 79 0.16 12.0 1. 27 4 33. 3 1. 7 11. 4 0. 3 9.6 0. 3 1. 24 79 0.15 12.0 1. 29 12.5 1. Q 5. 0 0. 4 4. 2 0.4 1. 86 0. 19 12. 0 13. 2 2. 0 3. 8 0. 3 3. 2 0. 3 1. 3O 86 0. 14 11. O 1. 14. 5 2. 20 3. 8 0. 3 3. 2 0. 3 1. 35 93 0. 16 12.0 1.31 11.1 1. 7 3.8 0. 3 6. 4 0. 6 0.87 24 0. 2 5. 5 1.05 11. 1 1. 7 7. 6 O. 6 3. 2 0. 3 1. 16 0. 12 9. 1 1. 30 13. 3 2.0 2. 5 0.2 10. 3 1. 0 0. 63 13. 3 2.0 12. 5 1.0 10. 3 1.0 0.72 1. 04

1 Per equivalent of sultonie acid, based on total N. N.

1 Normal salt would have 0.7% Ca, based on true N. N. Dowflake 77%.

4 1,200 grams of sulfonic acid used in this example.

In Examples 4 and 5, the preferred amounts of reagents were used. It will be seen that where the amounts of the reagents were decreased to 1.3 equivalents of calcium hydroxide, 0.2equivalent of calcium chloride and 0.2 equivalent of calcium acetate per equivalent of acid-hydrogen in the sour oil, the calcium content of the product was decreased (Example 3). On the other hand where the amounts of the reagents are increased to 1.5 equivalents of calcium hydroxide, 0.4 equivalent of calcium chloride and 0.4 equivalent of calcium acetate per equivalent of acid-hydrogen in the sour oil, a slight increase in calcium content of the product was achieved (Example 6). However, the increase is not. in proportion to the increase in calcium content of the reagent; and, difiiculties in filtration were encountered due to the excessive amounts of reagents employed. Again, where the calcium chloride and calcium acetate were kept constant at 0.3 equivalent and the calcium hydroxide content of the reagent slurry was increased to 1.9 (Example 7) or even 2.2 equivalents (Example 8) a slight increase in calcium content was achieved, but, again, filtration difficulties were encountered. If the calcium hydroxide and calcium acetate are held constant at the preferred ratio and the calcium chloride is increased to 0.6 equivalent, the calcium content of the product is decreased (Example 10). Increasing the calcium acetate content of the slurry in a significant amount above the preferred ratio resulted in a decrease in calcium content of the final product, even when the calcium hydroxide and calcium chloride were varied over wide limits (Examples 9, 11 and 12). This is believed to be due to the formation of complexes similar to those described in the grease art which are insoluble in oil and are removed during filtration. Generally, the preferred proportions found for the calcium reagents are also applicable to the reagent salts of the other metals contemplated herein, although some variation from these proportions in certain instances and in the case of certain metals provide products of higher metal content. Such variations in the amounts of reagent salts used are, therefore, within the scope of our invention. For example, where the metal constituent of the reagent salts is magnesium may be utilized for the successful preparation of the complex salt products having the high metal contents contemplated herein, but are not the exact amounts to be used in any and all cases.

A typical synthetic wax-aryl sulfonic acid, viz., waxbenzene (2-12) sulfonic acid was prepared as shown in the following example.

EXAMPLE 13 Preparation of wax-benzene (2-12) sulfonic acid A parafiin wax having an average of 24 carbon atoms per molecule and a melting point of 126 F. was chlorinatcd at a temperature of about 100 C. with chlorine gas until the weight of the wax had increased about 12 per cent. The chlorowax thus obtained was then blown with nitrogen to remove any occluded chlorine and hydrogen chlorine.

One thousand grams of the chlorowax were then mixed with 500 grams of benzene in a 3-neclced flask equipped with a stirrer, a reflux condenser and a thermometer. The mixture was heated to a temperature of 60 C. Aluminum chloride was then added slowly over a period of two hours. The addition of aluminum chloride was accompanied by a vigorous evolution of hydrogen chloride. The temperature was then raised to a temperature of C. and held there for one 'hour. The excess benzene was then removed by inverting the reflux condenser and heating to a temperature of 116 C. Two hundred milliliters of benzene were thus recovered. The mixture was cooled to a temperature of 60 C. and then another 1000 grams of chlorowax were added slowly. After completing the addition of this chlorowax, the temperature was raised to C. and held there for one hour. The product was allowed to stand overnight at a temperature of about 60 C., and then was separated from the sludge by decantation and filtration by suction through clay.

One thousand seven hundred and thirty-eight grams of the wax-benzene thus obtained were placed in a 3-necked flask equipped with a stirrer and a thermometer and heated to a temperature of 40 C. Eight hundred sixty-nine grams of oleum (15 per cent S03) were addedslowly to the wax-benzene from a dropping funnel at a rate regulated to maintain the temperature below 50 C. The addition of oleum consumed about 3 hours. The mixture was then stirred for an additional hour to ensure complete reaction. The mixture was then poured into 1000 milliliters of water and subsequently, 1810 grams. of mineral oil were added to the mixture. The mixture thus obtained was stirred thoroughly and then allowed to stand until the water separated into a layer. The water layer was then drained 01f. The product thus obtained was approximately a 50 per cent blend of wax-benzene sulfonic acid in mineral oil and had a neutralization number of 40.7.

It will be understood that a, wax-benzene prepared according to the foregoing procedure in which a quantity of chlorowax containing 2 atomic proportions of chloride and having a chlorine content of 12 per cent is reacted with 1 mole of benzene is designated wax-benzene (212). Similarly, wax-benzene (340) and waxbenzene (1-10) may be also prepared by the reaction of sufiicient amounts of chlorinated wax, containing 1-0. per cent by weight of chlorine, to provide 3 atomic proportions and 1 atomic proportion of chlorine per mole of benzene, respectively, in the reaction are useful in the invention. In general, the amount of chlorowax containing from about 10 to about 18 per cent by weight of chlorine used in the reaction is suflicient to supply between 1 and 4 atomic proportions of chlorine per mole of benzene used.

Two complex salts of wax-benzene (2-12) sulfonic acid, prepared as described in the above-example, were prepared, viz., (1) a complex acetate-chlorid'e-calcium sulfonate (Example 14) and (2) a complex acetate-chloridemagnesium sulfonate (Example 15).

TABLE II.PREPARATION F COMPLEX CALCIUM 1.8.6. grain grease.v makers? little 6% per cent Ca(OH)2, 1.68 equivalents) 170 cc. H2O

Procedure.-The calcium reagent was made by adding the acetic acid to a slurry prepared by dissolving the cal- The wax-benzene sulfonic acid was heated with stirring.

and with a moderate stream of nitrogen passing through it to approximately 75 C. The calcium reagent was then added slowly to the wax-benzene; sulfonic acid. over a one-hour period from a dropping funnel. When the addition was complete, more heat was applied and the water was removed by means of the Dean-Stark take-off. The reaction mixture was gradually heated to about 105 C. and, to ensure complete dehydration, held at this temperature for a period of about one hour.

Twelve grams of Hyflo filter aid were stirred into the product mixture which was then filtered through a Hyfio packed filter paper in a heated Biichner funnel. The product was a viscous brown oil.

EXAMPLE 15 Preparation of complex acetate-chloride magnesium waxbenzene (2-12) suljfonate This salt was prepared by a procedure identical to that used in Example 14, except that magnesium hydroxide, magnesium chloride and, magnesium acetate salt reagents were utilized in place of the corresponding calcium salts.

The details. relative to Examples 14 and 15 are given in Table II.

SALTS OF WAX-BENZENE (2-12) SULFONIO ACID Reagents 1 fggff Diluent Example Sammie Process Hydroxide Component Chloride Component Number #5 Oil,

3 5, Grams 4 Formula Grams gg Formula Grams gi g 14 40,0 Ca(OH); 18.6 1. 7 0.11011 6.4 0.3 15. 400 150 Mg( OH) 1 21. 7 2. 3 MgQl1.6Hz0 10. 4' 0. 3.

Reagents 1 Analysis of Product llIxamlple Carboxylate Component P um 81' ercent Total Base fizg Excess g Percent No. Poten- Formula Grams gg? Metal tiometrlc 14 CHQOOOH 5. 4 0. 3 2.14 Ga. 2 54 0. 56 2. 15 14 15.-- CHQOOOH 17. 6 0.9 1.63 Mg 87 0. 19 1. 87 29 3 Normal calcium sulfonate would have 1.39%

Ga based on true N. N. (39.5).

= This material contains about diluent oil. 4 A conventionally refined Mid-Continent (parafiinic) neutral distillate oil having a K. V. of 100 sec. at 100 F.

EXAMPLE 14 Preparation of complex acetate-chloride calcium waxbenzene (212) sulfonaie Materials EXAMPLES 16-28 A number of complex salts of petroleum sulfonic acids were prepared using salt reagents of metals other than calcium (Examples 16-20). A number of mixed metal 400 grams wax-benzene 2-12) sulfonic. acid (total calcium salts were also prepared (Examples 21-25). The

5.4 grams acetic acid (glacial) (0.3 equivalent based total N. N.)

6.4 grams dowtlake (77 per cent CaCIz, 0.3 equiv alent based on total N. N.)-

procedure used was that of Example 2. In several of these examples, aliphatic acids other than acetic acid were used, such as formic acid (Example 28), propionic acid (Example 26) and heptylic acid (Example 27). Details. as to these examples are given in Table HI.

TABLE [11.-METAL AND MIXED METAL COMPLEX SALTS OF PETROLEUM BULFONIO AGID Reagents Employed For 400 Grams Sulfonio Acid-Total N N=24.1; True NN=19.6

Example Hydroxide Component Chloride Component Carboxylate Number ponent Formula fig Grams Formula ggg Grams Formula 16 Mg(OH): 1. 7 8. 5 MgClz.6H20 0. 3 5. 3 CHaCOOH 17 Mg(OH)2 2. 10. 0 MgClafiEzO 0. 3 5. 3 0131000011 18 Mg(OH)2 2. 3 11. MgC1z.6H2O 0. 3 5. 3 CHaCOOH 19 Ba(OH)28HzO 1. 7 46 1321012213120 0. 6 12. G CHaCOOH 20 NaOH 1. 7 12. 1 NaCl 0. 3 3. 02 GHBOOOH 21 08(OH): 1. 7 11. 1 MgClziiHzO 0. 3 5. 3 CHSOOOH 22 0&(0H): 1. 7 11. 1 ZnCl: 0. 3 3. 7 H300 23 Mg(OH)z 1. 4 7. 3 Z1101: 0. 3 3. 7 Ca(C2HaO2)2 H 24 Ba.(OH)z.8H2O 1. 4 38 021012 0. 3 3. 8 09.201102. 2 25 Mg(0H)l 1. 4 7.0 021012 0. 3 3. 8 Ca OAc)z.HzO 26 Ca(OH): 1. 7 11. 1 08.012 0. 3 3. 8 CHaCHzCOOH 27 Ca(OH): 1. 7 11. 1 09.012 0. 3 3. 8 CH3(CH2)5COOH 28 Ca(OH): 1. 7 11. 1 OaCl: 0. 3 3. 8 HCOOH Reagents Enplloyed FXrOO rams u omo c1 Total NN=24.1; Tru Analysis Of Product NN=19.6

Example Number 0 b 1 t C t at oxy a e omponen Total Total Percent Mei-5a1 Metal Percent Percent Base N o. E uiva- Water 1103? Equiva 1112 51 1 0 Potent" fl Grams cc lents ornetrrc 0. 3 3. 1 100 0.79 (Mg).. 1. 89 89 0. 22 9. 7 0. 6 6. 2 100 0.94 (Mg) 2. 23 2. 23 123 0. 26 17 0. 9 9. 3 100 1.07 (Mg) 2. 6 2. 6 160 0. 31 0. 3 3. 2 100 4.6 (Ba)--- 2. 0 100 07 7. 1 0. 3 3. 1 100 1.30 (Na) 1. 63 1. 63 63 0. 11 11. 4 0. 3 3. 1 100 1.00 (0a)-- 1. 41 1. 57 57 0. 19 4. 3

0.07 (Mg) 16 0. 3 3. 1 150 1.14 (0a).- 1. 6 1. 85 85 0. 18 13 0.3 (Zn) 254 0. 3 4. 6 150 0.14 (C3)" 0. 2 1. 63 63 0. 29 6. 5

0.54 (Mg) 1. 27 0.18 (Zn 156 0. 3 4. 6 160 0.20 (C 0. 29 1. 77 77 0. 23 7. 1

0.42 (Mg) 1. 00 0. 3 3. S 100 1.23 (Ga) 1- 1. 77 1. 77 77 0. 18 11 0. 3 6. 7 100 1.23 (0a)-. 1. 77 1. 77 77 0. 10 11 0. 3 2. 4 100 1.14 (0a)-- 1. 63 1. 63 63 0. 14 10 Engine evaluation parative purposes, the results obtained with the blank oil T 0 demonstrate the ability of the complex chlorideare also Included. The 011 used these. tests was an e b 1a t at 1 U1 f0 ate u of the invention as SAE grade, acid-refined coastal o1l havlng a K. V. at M e m a s S 100 F. of 132.7 and at 210 F. of 9.82. Both the blank lubricating oil detergents, We have prepared oil blends of a. number of such salts and tested these oil blends in the CFR diesel D-2l detergency test. Table IV shows the tabulated results for the various oil blends. For comoil and the oil blends contained 1.0% of antioxidant (pinene-PzSa product). These test data show the high efficiency of the complex salts of the invention as detergents in engine oils.

TABLE IV.-OFR COMET DIESEL TEST (D-21) (HIGH SULFUR FUEL-SAE 30 BASE OIL) Product 01' Example No.

Piston Cleanliness Rating At Hours Sulfonate Type Percent Composition Of Reagent Additive Petroleum.

Diesel (D-21') detergency test This test determines the effectiveness of the lubricating oil in preventing piston deposits and top ring wear.

A single cylinder CFR, 4-cycle, super-charged, diesel engine is used. The operating conditions are as follows:

Oil temperature F 175 Jacket temperature F" 212 Speed R. P. M 1800 Brake load H. P 7.5 Oil addition every 8 hours starting at 4 hours (1 /2 gal. sample used) Heat input B. t. u./min. 1260 The duration of the test is 60 hours. The fuel used is a N0. 2 fuel oil containing 1 per cent sulfur. The results are reported in terms of piston cleanliness ratings.

Various grades of lime, such as grease makers lime, Bell-Mine chemical grade hydrated lime and chemically pure lime, may be used in preparing the complex calcium salts of this invention. However, grease makers lime is preferred because of its high purity, small particle size and its property of being wet by oil.

The amount of complex salt product utilized in a lubricating oil will depend upon the particular oil and the application for which it is designed. Generally, amounts ranging from about 0.1 up to about 20 weight per cent may be used, the usual amount being from about 0.5 to about 10 weight per cent.

The complex salt products of this invention may be used in lubricating oil compositions containing other addition agents designed to improve the oil in different respects, e. g., antioxidants, extreme pressure agents, pour point depressants, viscosity index improvers, defoamants, etc.

Although the complex salts of this invention are intended primarily for use as lubricating oil additives, they are also adaptable for use in other applications, e. g., they find application in the manufacture of detergent soaps and are useful as dispersants and rust reventives. They may also be used as additives for cutting and textile oils.

Although the preparation and utility of certain specific representative complex salt products, and oil compositions thereof have been described in detail herein, it is not intended that the invention be limited in any Way thereby, but that it include such variations and procedures and such products and compositions as come within the spirit and scope of the accompanying claims.

We claim:

1. A complex metal salt of a hydrocarbon-soluble sulfonic acid produced by the method which comprises the steps of: (l) forming a mixture of a hydrocarbon solution of the sulfonic acid with water and a reagent combination which will provide in said mixture at least about 1.4 equivalents of metal hydroxide, at least about 0.3 equivalent of metal chloride and at least about 0.3 equivalent of an aliphatic metal carboxylate having from 1 to about 20 carbon atoms in the aliphatic portion thereof; the equivalents of said metal hydroxide, metal chloride and metal carboxylate being based on the total equivalents of acid-hydrogen present in the hydrocarbon solution of the sulfonic acid and the metal constituent of said metal hydroxide, metal chloride and metal carboxylate being a metal selected from groups I and ii of the periodic table of the elements, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering oii insoluble material.

2. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being 14 based on the total equivalents of acidrhydrogenipreseut in. said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

3. A complex metal salt of an oil-soluble synthetic wax-benzene sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the wax-benzene sulfonic acid, in the presence of water, with at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering ofi insoluble material.

4. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at, least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of formic acid, the equivalents of said calcium hydroxide,

calcium chloride and formic acid used being based onthe total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially comp-letely dehydrating the reaction mixture formed instep and (3) filtering oft" insoluble material.

5. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at least about 1.7 equivalents of magnesium hydroxide, at least about, 0.3 equivalent of magnesium chloride and at least about 0235 equivalent of acetic acid, the equivalents of said mag nesium hydroxide, magnesium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed, in step 1 and (3) filtering off insoluble material.

6. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the sulfonic acid, in the presence or" water, with at least about 1.7 equivalents of barium hydroxide, at least about 0.3 equiv alent of barium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said barium hydroxide, barium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering oil insoluble material.

7. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering of? insoluble material.

8. A complex metal salt of an oil-soluble synthetic wax-benzene sulfonic acid produced by the method which comprises the steps of (l) intimately contacting an oil solution of the wax-benzenesulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium' chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering otf insoluble material.

9. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of calcium hydroxide, at least about 0.3' equivalent of calcium chloride and at least about 0.3 equivalent of formic acid, the equivalents of said calcium hydroxide, calcium chloride and formic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

10. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of magnesium hydroxide, at least about 0.3 equivalent of magnesium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said magnesium hydroxide, magnesium chloride and acetic acid used being based on the total equivalents of acidhydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

11. A complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of barium hydroxide, at least about 0.3 equivalent of barium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said barium hydroxide, barium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

12. A mineral lubricating oil containing a minor proportion, sutficient to improve the detergent ability of said oil, of a complex metal salt of a hydrocarbonsoluble sulfonic acid produced by the method which comprises the steps of: (1) forming a mixture of a hydrocarbon solution of the sulfonic acid with water and a reagent combination which will provide in said mixture at least about 1.4 equivalents of metal hydroxide, at least about 0.3 equivalent of metal chloride and at least about 0.3 equivalent of an aliphatic metal carboxylate having from 1 to about 20 carbon atoms in the aliphatic portion thereof, the equivalents of said metal hydroxide, metal chloride and metal carboxylate being based on the total equivalents of acid-hydrogen present in the hydrocarbon solution of the sulfonic acid and the metal constituent of said metal hydroxide, metal chloride and metal carboxylate being a metal selected from groups I and II of the periodic table of the elements, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

13. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of. (1) intimately contacting an oil solution of the sultonic acid, in the presence of Water, with at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid. used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

14. A rnineral lubricating oil containing a minor pro- Cir ' step 1 portion, sulficient to improve the detergent ability of said oil, of a complex metal salt of an oil-soluble synthetic wax-benzene sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the wax-benzene sulfonic acid, in the presence of water, with at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

15. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of formic acid, the equivalents of said calcium hydroxide, calcium chloride and formic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering otf insoluble material.

16. A mineral lubricating oil containing a minor proportion, suflicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at least about 1.7 equivalents of magnesium hydroxide, at least about 0.3 equivalent of magnesium chloride and at least about 0.3

equivalent of acetic acid, the equivalents of said magne-, sium hydroxide, magnesium chloride and acetic acid portion, sufficient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid, in the presence of water, with at least about 1.7 equivalents of barium hydroxide, at least about 0.3 equivalent of barium chloride and at least about 0.3

equivalent of acetic acid, the equivalents of said barium hydroxide, barium chloride and acetic acid used being based on thetotal equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering oft insoluble material.

18. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3

equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in and (3) filtering oil insoluble material.

19. A mineral lubricating oil containing a minor proportion, suflicient to improve the detergent ability of said oil, of a complex metal salt of an oil-soluble synthetic Wax-benzene sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the wax-benzene sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said calcium hydroxide, calcium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

20. A mineral lubricating oil containing a minor proportion, suflicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.4 equivalents of calcium hydroxide, at least about 0.3 equivalent of calcium chloride and at least about 0.3 equivalent of calcium formate, the equivalents of said calcium hydroxide, calcium chloride and calcium formate used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

21. A mineral lubricating oil containing a minor proportion, sufficient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of magnesium hydroxide, at least about 0.3 equivalent of magnesium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said magnesium hydroxide, magnesium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

22. A mineral lubricating oil containing a minor proportion, sufiicient to improve the detergent ability of said oil, of a complex metal salt of a petroleum sulfonic acid produced by the method which comprises the steps of (1) intimately contacting an oil solution of the sulfonic acid with an aqueous reagent slurry containing at least about 1.7 equivalents of barium hydroxide, at least about 0.3 equivalent of barium chloride and at least about 0.3 equivalent of acetic acid, the equivalents of said barium hydroxide, barium chloride and acetic acid used being based on the total equivalents of acid-hydrogen present in said oil solution of the sulfonic acid, (2) substantially completely dehydrating the reaction mixture formed in step 1 and (3) filtering off insoluble material.

References Cited in the file of this patent UNITED STATES PATENTS Re. 23,082 Zimmer Jan. 25, 1949 2,467,176 Zimmer Apr. 12, 1949 2,553,422 OHalloran May 15, 1951 30 2,585,520 Van Ess Feb. 12, 1952

Claims

1. A COMPLEX METAL SALT OF A HYDROCARBON-SOLUBLE SULFONIC ACID PRODUCED BY THE METHOD WHICH COMPRISES THE STEPS OF: (1) FORMING A MIXTURE OF A HYDROCARBON SOLUTION OF THE SULFONIC ACID WITH WATER AND A REAGENT COMBINATION WHICH WILL PROVIDE IN SAID MIXTURE AT LEAST ABOUT 1.4 EQUIVALENTS OF METAL HYDROXIDE, AT LEAST ABOUT 0.3 EQUIVALENT OF METAL CHLORIDE AND AT LEAST ABOUT 0.3 EQUIVALENT OF AN ALIPHATIC METAL CARBOXYLATE HAVING FROM 1 TO 20 CARBON ATOMS IN THE ALIPHATIC PORTION THEREOF; THE EQUIVALENTS OF SAID METAL HYDROXIDE, METAL CHLORIDE AND METAL CARBOXYLATE BEING BASED ON THE TOTAL EQUIVALENTS OF ACID-HYDROGEN PRESENT IN THE HYDROCARBON SOLUTION OLF THE SULFONIC ACID AND THE METAL CONSTITUENT OF SAID METAL HYDROXIDE, METAL CHLORIDE AND METAL CARBOXYLATE BEING A METAL SELECTED FROM GROUPS I AND II OF THE PERIODIC TABLE OF THE ELEMENTS, (2) SUBSTANTIALLY COMPLETELY DEHYDRATING THE REACTION MIXTURE FORMED IN STEP 1 AND (3) FILTERING OFF INSOLUBLE MATERIAL.