RECOVERY OF GOLD BY USING BIOMASS WASTES CONTAINING POLYPHENOL COMPOUNDS

摘要

New recovery method of gold from chloride media was developed by using adsorption gels prepared from biomass wastes containing polyphenol compounds: waste persimmon peel and lignophenol which is prepared from wood wastes by immobilizing many phenol groups on wood lignin by a simple method. Gold can be recovered as elemental gold from hydrochloric acid over a wide concentration region while other precious metals such as platinum and palladium as well as base metals are not practically adsorbed. The maximum adsorption capacities of gold on persimmon peel gel and lignophenol gel were as high as 5.5 and 1.9 mol/kg-dry gel, respectively.