Preparation of metallic silver from Ag 2S slurry by direct hydrogen reduction under hydrothermal conditions

Abstract

Metallic silver has been prepared by direct hydrogen reduction of Ag 2S in basic slurry under hydrothermal conditions. The XRD pattern and SEM micrographs of the reaction product are given. Metallic silver was predominant in the reduction product obtained by using ZnO as additive and PdCl 2 as catalyst at 220 °C, pH 12.0 and 2–3 MPa of partial hydrogen pressure for 4 h.