Patented Dec. 24, 1946 ‘umr 2,413,161 _ s'r'r 2,413,161 SURFACE ACTIVE AGé Ernst Zerner, New York, and William Kaplan, Brooklyn, N. Y., assignors, by mesne assign ments, to Sun Chemical Corporation, New York, N. Y., a corporation of Delaware ' 'No Drawing. Application June 22, 1944, Serial No. 541,664 1 Claim. (Cl. 260-505) _ i 2 This invention relates to improvements in methods of producing alkyl-aromatic sulfonates useful as surface active agents and for detergent, it is unnecessary to separate the unsaturated part out of a cracked mineral oil before condensation even when only 10-35 per cent unsaturated hy wetting and similar purposes. It relates more drocarbons are present. The condensation of the particularly to improvements in methods of pro unsaturated material with an aromatic hydro ducing higher alkyl-aromatio sulfonates from carbon as benzene, toluene, xylene still takes non-aromatic hydrocarbon mixtures by conden place with a reasonable yield. After condensa sation with aromatic compounds with the aid of tion, ?rst the excess of the aromatic hydrocarbon aluminium chloride as a condensation catalyst, and then the higher boiling saturated hydrocar followed by sulfonation of the condensation 10 bon is distilled off; the latter being deodorized product. and water-clear and thus presenting a product It is a well known fact that nuclearly sulfon of increased value. ated alkyl-aromatic compounds are valuable de Another object of this invention is to increase tergents, either as such or'in the form of their the yield of the process. This can be performed alkali salts. Due to their excellent qualities and 15 according to this invention by using gaseous hy their comparatively low cost, they are dominating drogen chloride as an additional catalytic agent. the market. It is probable that some part of the hydrogen One known method of preparing said sulfon chloride adds to the double bond and is split off ated alkyl-ar0matic compounds consists in chlo again in condensation so that a new addition to rinating re?ned Pennsylvanian kerosene, con 20 another part of so far una?ected unsaturated densing the chlorinated product with benzene, hydrocarbon may take place. Without using hy toluene, or xylene in the presence of aluminium drogen chloride, a substantial part of the un chloride and sulfonating the reaction product saturated hydrocarbon does not condense, it thereafter. Although the chemical character of rather undergoes some other reaction leading to the ?nal product is known in general, it repre 25 formation of tar. sents a mixture of numerous compounds differing Another advantage of promoting the condens according to the raw material used and the work ing effect of aluminium chloride as described, is ing and re?ning methods applied. the fact that fewer undesirable by-products are The chlorination needs a very expensive equip formed. While ‘the yield of the condensation ment. Furthermore, mono, di, and poly-chlori 30 product without the addition of hydrogen chlo nated compounds are simultaneously formed and ride amounts to about 30 per cent of the theo have to be separated at some stage of manufac retical value (based on content of unsaturated turing by certain purifying methods. hydrocarbon), it is raised to about 45 per cent when hydrogen chloride is bubbled through the reaction mixture, in the ?rst ?ve minutes. We have found that bromine and hydrogen bromide are still more effective, apparently be It is one object of this invention to eliminate the step of chlorination. This is performed ac cording to this invention by working with unsat- ' urated instead of saturated hydrocarbons as a raw material for the Friedel—Crafts condensa tion. This enables us to use a raw material which cause the addition of these materials to the dou ble bond proceeds much faster than the addi is otherwise of very little value. 40 tion of hydrogen chloride. This method of oper The condensation of unsaturated aliphatic hy ation raises the yield to about 60 per cent of the theoretical value. ' drocarbons with aromatic hydrocarbons like ben The main object of this invention is to use zene, toluene, xylene, by a Friedel-Crafts reac cracked mineral oil containing only 35 per cent or tion is well known. The use of this reaction for manufacturing detergents by sulfonating the 45 less unsaturated hydrocarbon as a raw material alkyl-aromatic condensation products is equally for a Friedel-Crafts reaction with benzene, tolu known and disclosed in several patents. Accord ene or xylene and to sulfonate the so-obtained condensation product after removing the excess of aromatic and the unattacked saturated hy ization of gaseous ole?ns as formed in cracking 50 drocarbon by distillation. of mineral oils for the condensation. According Other objects of the invention will be obvious ing to one of the known processes, e. g. ole?ns are used as starting material, obtained by polymer to another process the unsaturated part of a , and will appear hereinafter. cracked kerosene is extracted e. g. with liquid The cracked mineral oils which we employ sulfur dioxide and is used as a starting material. must not be too low in boiling point and/molecu Now, we have found the surprising fact that 55 lar weight. It is common knowledge that any 2,413,101 3 surface active product has to contain a hydro After standing for twelve hours, the sulfonation mixture separates into three layers: A lower layer philic and a hydrophobic part and there. has to of' spent acid, a middle layer oi’ 40 parts of alkyi be a certain balance between these constituents. Therefore, only such sulfonated alkyl aromatic benzene sulfonate, and an upper layer of hydro compounds are appreciable detergents in which carbon. The alkyl-benzene sulionate has an acid the side chain which represents particularly the number of about 400 indicating that about 20 per hydrophobic part has a certain minimum length. cent of free sulfuric acid is present. The alkyl On the other hand, this side chain can not be benzene sulfonate is treated with a small quan too long because the hydrophobic properties oi’ tity of water and enough sodium bicarbonate the sulfonated products would be too high and, 10 togive a paste which, when dried, contains about therefore, their calcium and magnesium salts 40 per cent of active‘ material. The paste is then dried and ground. A powder possessing ex would not be soluble enough. In other words. if cellent detergent properties is obtained. the side chain is too lens, the detergent would not be fast enough to hard water. It has been our experience that the boiling range of our un saturated hydrocarbon serving as a raw material Similar results are obtained by working with toluene or xylene instead of benzene. should be about 150 to 300° C. under atmospheric pressure. Expressed in length of the molecule, they should contain between’ 8 and 16 carbon The same vprocedure as described in Example atoms. Most of the sulfonated alkyl aromatic deter gents on the market are manufactured by using Pennsylvanian petroleum as a starting material, Example I] 20 I is performed again, except that dry hydrogen chloride is bubbled through the condensation mixture for the ?rst ?ve minutes. The con densation is then continued for only two hours and the reaction mixture is worked up as de scribed before.v A yield of 60 parts of alkyl-ben or other petroleum which, by re?ning, has been made similar to Pennsylvanian petroleum. With 25 zene sulfonate is obtained. out insisting on some exact chemical constitution Example III of our compounds, we would like to emphasize that we are not forced to work with just Pennsyl vanian mineral oil which primarily contains open The same procedure as described in Example I is performed again, except that 2 parts of dry chain hydrocarbons. As shown in the examples 30 bromine are added to the kerosene and the re action is stopped after two hours. A yield of given below, for our purposes mineral oil frac 80 parts of alkyl-benzene sulfonate is obtained. tions from Texas containing a considerable part of naphthenic hydrocarbons are suitable without Example IV any previous re?ning. The same procedure as described in Example The invention will be illustrated by the fol 35 lowing speci?c examples. It will be realized by r II is performed again except that hydrogen bro; mide is substituted for hydrogen chloride. A those skilled in the art that the invention is yield of 75 parts or alkyl-benzene sulfonate is not limited thereto except as indicated in the appended patent claim. The parts are by weight, We claim: . the temperatures are in degrees centigrade. 40 In the process of manufacturing sulfonated a1 Example I kylated monocyclic aromatic hydrocarbons by condensation of unsaturated aliphatic hydrocar 400 parts of a kerosene fraction, containing ap bons with benzene and its homologues under the proximately 25 per cent of unsaturated hydrocar in?uence of aluminum chloride by means of a bon, boiling from 160 to 240°, obtained by the cracking of a Texas oil, is added with agitation ' Friedel-Crafts synthesis and by sulfonating the condensation product, the step which comprises to 400 parts of benzene and 20 parts aluminium condensing cracked mineral oil fractions boiling chloride over a period of 20 minutes. The mix under normal pressure between 150-300” C., and ture is vigorously stirred at 55° for three hours. After 12 hours, the clear upper layer is decanted 50 containing not more than 10-35 per cent. of un saturated hydrocarbons with monocyclic hydro from the tarry residue and stirred for 10 minutes carbons of the class consisting of benzene, tolu with one part water and four parts Filtrol. After ene, and xylene, in the presence of aluminum ?ltration, the liquid is distilled until a boiling chloride. ‘ point of 240° is reached. The residue is sulfonat obtained. ed with an equal volume of 100 per cent sulfuric acid for one hour at 55°. The sulfonation mixture is stirred for a few minutes with 5 parts of water. ' ' ‘ ERNST ZERNER. WILLIAM KAPLAN.