Abstract: A method for aralkylation of benzene or alkylbenzenes which is characterized in that an aromatic olefin having a double bond or double bonds which are conjugated with the benzene ring is added to the benzene or alkylbenzenes in the presence of at least one member of catalyst selected from the group consisting of the compounds represented by the general formula:C.sub.n F.sub.2n+1-m Cl.sub.m SO.sub.3 Hin which the symbol n is an integer from 1 to 5 and m is 0 or 1. Since the selectivity to the aromatic olefin in the reaction is excellent, the mixture of aromatic olefins and aliphatic olefins can be employed as one of the starting material.

Abstract: A method for preparing polycyclic aromatic hydrocarbons with excellent yield and selectivity but without the formation of cyclic dimers and other undesirable by-products. In the method of the present invention, styrene, .alpha.-methylstyrene, .beta.-methylstyrene and/or vinyltoluene is dimerized and/or codimerized to produce unsaturated dimer and/or codimer in the first step reaction and said unsaturated dimer and/or codimer is caused to react with an aromatic hydrocarbon or hydrocarbons in the second step reaction, and both the first and second step reactions are carried out in the presence of a catalyst which is represented by the general formula: RCF.sub.2 SO.sub.3 H, in which the symbol R is Cl, F or C.sub.n F.sub.p CL.sub.2n+1-p, wherein n is an integer from 1 to 3 and p is also an integer from 1 to 2n+1.

Abstract: An excellent fat-liquoring composition for leather comprises 100 parts by weight of a neutralized polybutene sulfonation product, 1-100 parts by weight of a polybutene and 1-100 parts by weight of one or more fatty acid salts. The polybutene employed herein has a number average molecular weight of 250-1500, is normally in a liquid form, and is obtained by polymerizing a mixed C.sub.4 fraction in the presence of a Friedel-Crafts type catalyst. The polybutene thus prepared is sulfonated with sulfur trioxide or chlorosulfonic acid with or without a diluent such as air, nitrogen, carbon dioxide or sulfur dioxide and liquid solvents, etc. to obtain a polybutene sulfonation product. The polybutene sulfonation product is neutralized with an aqueous solution of alkali metal hydroxides or ammonia to prepare neutralized polybutene sulfonation products.