Recovery of precious metals from chloride solution by magnetite.

Batch-sorption tests were carried out on the recovery of gold and platinum from NaCl solution by commercial grade magnetite powder, looking at the effect pH, contact time, and precious metal and NaCl concentration had on recovery. Au and Pt had similar pH dependent recovery curves, with peaks at pH 6-7. At this pH range, a maximum of 4.4 micro mol Au/g Fe3O4and 3.0 micro mol Pt/g Fe3O4 were recovered after 24 h at an initial metal concentration of 0.05 mol/m3. Metal recovery increased with increasing initial precious metals concentration, and decreased with high NaCl concentration. SEM images showed that the gold had agglomerated and was deposited on the magnetite surface.
Batch-sorption tests were carried out on the recovery of gold and platinum from NaCl solution by commercial grade magnetite powder, looking at the effect pH, contact time, and precious metal and NaCl concentration had on recovery. Au and Pt had similar pH dependent recovery curves, with peaks at pH 6-7. At this pH range, a maximum of 4.4 micro mol Au/g Fe3O4and 3.0 micro mol Pt/g Fe3O4 were recovered after 24 h at an initial metal concentration of 0.05 mol/m3. Metal recovery increased with increasing initial precious metals concentration, and decreased with high NaCl concentration. SEM images showed that the gold had agglomerated and was deposited on the magnetite surface.