Recovery of Mg from H2SO4 Leaching Solution of Serpentine to Precipitation of High-Purity Mg(OH)2 and 4MgCO3·Mg(OH)2·4H2O

This paper describes a leaching-purifying-precipitation process to recover magnesium from serpentine acid-leaching solution and synthesize high purity Mg(OH)2 4MgCO3·Mg(OH)2·4H2O. Fe, Al, Cr in the leaching were removed using oxidation precipitation method with active MgO as precipitant H2O2 an oxidant. Ni, Co Mn by Na2S obtain pure MgSO4 solution. Mg2+ ions first precipitated NH3·H2O Mg(OH)2, followed NH4HCO3 A small part of coprecipitates form MgSO4·5Mg(OH)2·3H2O. The was aged diluted NaOH remove sulfur; two-stage percentage Mg is 96.3%. has 98.48% sulfur content 0.28%. provides promising for high-efficiency recovery large-scale production serpentine.