Surface active agent

Claim 1

A water soluble surface active agent obtained by sulfonating a reaction product boiling higher than hydrocarbons contained in a mixture and not lower than 260° C., under sulfonating conditions, followed by neutralization, which reaction product is obtained by treating said mixture in liquid phase in the presence of an acid catalyst at a reaction temperature of 0° to 330° C. to alkylate aromatics with aliphatic olefins followed by distillation, said mixture consisting of: (A) 20-95 weight percent of a thermal-cracked oil distillate obtained from a delayed coking process for coking a petrolic heavy residual oil at a temperature not lower than 400° C. and not exceeding 700° C., said distillate containing aliphatic olefins; and, either (B) 80-5 weight percent of one or more members boiling in the range of 150° to 250° C. and selected from the following (a) through (c): (a) a thermal-cracked by-product oil distillate obtained by thermal cracking of a petrolic light oil at a temperature of 750° to 850° C. followed by treatment for reducing the content of unsaturated compounds; (b) an reformate distillate obtained by catalytic reforming of a petrolic light oil boiling in the range of 50° to 250° C., followed by treatment for reducing the content of unsaturated compounds if necessary; and (c) an aromatic distillate consisting mainly of aromatic hydrocarbons and obtained by separation from said thermal-cracked by-product oil distillate (a) and/or said reformate distillate (b); or (C) 80-5 weight percent of aromatic hydrocarbons having a boiling range lower than 150° C. and not having an aliphatic double bond.