METHOD OF PREPARING A DISPERGATOR - A DILUTING AND STABILIZING AGENT FOR WATER DISPERSIONS OF HARD SUBSTANCES

摘要

Sulphonated dispersants are prepared by a process comprising: - bringing liquid or gaseous sulphur trioxide into contact under sulphonation conditions with a solution of a tar in liquid sulphur dioxide, - removing the sulphur dioxide from the reaction mixture by vaporization and recovering the sulphonated tar, and - salifying the sulphonated tar with an aqueous solution of an alkaline metal hydroxide or ammonium hydroxide. The sulphonated dispersants prepared in this manner are completely water-soluble and are particularly useful as fluidifying and stabilizing agents in aqueous dispersions of solids such as coal and cement.