Germanium Recovery Using Ion-Exchange Membrane and Solvent Extraction

Abstract

Germanium is a kind of rare metal. For the recovery of germanium ion, the novel recovery process is proposed using the complexation of germanium ion with catechol in solution; germanium ion is complexed with catechol forming anion, and then the anion-containing solution is flowed through quaternary-ammonium-group-containing membrane. In permeation mode, germanium ion is adsorbed to the membrane with catechol via ionic interaction. In actual wastewater of solar panel, silicate ion existed with germanium ion. At pH 3.0, germanium ion was selectively adsorbed to the membrane in the presence of silicate ion. The remained catechol in the effluent from the membrane was removed by solvent extraction with TOPO.