HYDROTROPES IN SOAP FLOTATION: A CRITICAL REVIEW

Abstract

In this study efficiency of soap flotation when the hydrotrope was used along with the flotation reagents especially collectors for different type of minerals is reviewed. It is known that for flotation of salt type minerals soaps are used as collectors. The soap collectors when used along with hydrotropes as promoters in flotation yielded better flotation efficiency along with the reduced usage of collectors (soaps). Hydrotropes the compounds that soulibilises hydrophobic compounds in aqueous solution. Hydrotropes are known to be the promoters in flotation. So far hydrotropes such as urea, sodium benzoate, sodium citrate, and sodium salicylate and tri sodium citrate are used along with soap collectors for soap flotation of phosphate minerals resulted in higher efficiency with reduced usage of collector. The asset of certain properties like the solvent character, independent of pH, high selectivity, non-flammability, cheap and easy availability of hydrotropes makes these compounds superior to other solubilization compounds. They have the ability to influence the micelle and microemuslions. Hydrotropes exhibit the aggregation behavior above minimum hydrotropic solution (MHS).Above MHC the solubility of the organic compound in aqueous phase increases significantly .The advent of hydrotropes and their  role in flotation of remaining  metallic and non metallic ores is still to researched.