Application of ion exchange for recovery of noble metals

Abstract

The production of noble metals has started to shift towards using different types of wastes. The leaching solutions collected during the processing of waste have low concentrations of noble metals; therefore, it forces the use of sorption methods in recovery technology. This work focused on recovering noble metals with a technological solution, obtained during the processing of waste from refining processes. The research consisted of a set of experiments using a batch method that enabled determination of the parameters of the process and selection of the leading resins. Sorption isotherms were determined and kinetic studies were conducted, along with the preliminary elution tests with the use of different eluents. Cementation experiments were the final part of the research. During the experiments, it was concluded that the leading resins for the sorption of noble metals were Puromet MTS9200, Puromet MTS9850, and Lewatit K 6362. The volume ratio Vr:Vs = 1:10 and the reaction time 15–30 min could be used as basic conditions to conduct the experiments in the column; the solution of thiourea in hydrochloric acid can be used as an eluting agent from which noble metals could be cemented using powder zinc.