THE SEPARATION AND ISOLATION OF GOLD BY SELECTIVE EXTRACTION AND TRANSPORT THROUGH A POLYURETHANE ETHER-TYPE MEMBRANE

The separation and isolation of gold(III) by selective extraction and transport through a ether-type polyurethane membrane was studied. Gold was found to be extracted into the membrane in strongly acidic soluti ons of HCl and HBr as the HAuBr4 and HAuCl4 complexes. Once extracted, the HAuCl4 and HAuBr4 complexes diffuse through the membrane and are recovered quantitatively in a receiving cell solution. This phenomenon was studied for the separation of a variety of binary metal solutions as well as for the separation of gold from a solution of gold ore. Th e preconcentration of gold was also achieved by adjusting the starting and receiving cell solution volumes.