Tungsten extractive metallurgy: A review of processes and their
The natural tungsten-bearing minerals need to be treated by minerals beneficiation to obtain a tungsten concentrate of around 65% WO 3. ... Tungsten is first extracted as isopolytungstate ions in the organic phase, meanwhile the sodium is separated as a Na 2 SO 4 solutions. Then the isopolytungstate is stripped by ammonia solution into …