THE present review covers contributions to the art of sulfonation reported in the published literature from about 1941 to the forepart of 1947. In general, this review embraces material reported in Chemical Abstracts as well as information about sulfonation processes used in Germany as described in various government reports-e.g., British Intelligence Objectives Sub-Committee Final Reports (BIOS reports), Field Information Agency Technical Final Reports of the U. S. Government (FIAT reports), and others. The review is limited to INDUSTRIAL AND ENGINEERING CHEMISTRY Vol. 40,No. 9 of unreacted oil suitable for recycling. The I.G. Farbenindustrie manufactured Mersolates-i.e., mixtures of Ci6 and Ci6 alkyl