ABSTRACT
I. INTRODUCTION Alkyldiphenyl oxide disulfonates were first identified in 1937 by Prahl [1] of E.I. du Pont de Nemours & Company. They were produced by condensation of a sulfuric acid ester of an aliphatic or cycloaliphatic alcohol with diphenyl oxide. Because of the large excess of sulfuric acid ester necessary to drive the reaction to completion, reaction yields were low. Only a few investigations followed this initial work [2,3]. In 1958 Steinhauer [4] was able to develop a commercially viable process. This made it possible to evaluate alkyldiphenyl oxide disulfonates in various applica tions where the basic physical properties of the chemistry were hypothesized to be of value. The original observations showed that branched alkyldiphenyl oxide disul fonates were much more soluble in electrolytes than alkylbenzene(mono)sulfonates and were in fact more soluble than other conventional surfactants of the time. The process developed by Steinhauer [4] produced alkyldiphenyl oxide with 1 to 1.3 alkyl substituents on the diphenyl oxide intermediate. Reaction of this mixture with either chlorosulfonic acid or sulfur trioxide produced the disulfonates. This reaction was carried out as a batch process using a nonreactive solvent such as a liquid poly chlorinated aliphatic hydrocarbon (i.e., methylene chloride, carbon tetrachloride, perchloroethylene, or ethylene dichloride) as diluent and heat exchange agent.
