Two Synergic Pairs for the Extraction of Ammoniacal Ni.
Penner LR; Russell JH; Campbell MJ
Paper in Solvent Extraction 1990 :423-428
The U.S. Bureau of Mines has studied extraction of ni from ammoniacal sulfate solution for two solvent extraction systems that show extraction synergy. The first system uses the extractants 2- hydroxy-5-nonyl benzophenone oxime (lix 64n) and 7-(4-ethyl-1- methyloctyl)-8-hydroxyquinoline (kelex 100). At ph 10, ni extraction synergy is seen from this chelate-chelate pair in both equilibrium tests and kinetic tests. The second system used kelex 100 and dinonylnaphthalene sulfonic acid (dnnsa), a chelate-acid pair. No equilibrium extraction synergy is observed for the second pair at ph 10, but of more practical importance, kinetic synergy is found. In only 10 min of mixing with 0.10 M extractant, ni extraction is 53 pct for the best lix 64n/kelex ratio (3:1) and 87 pct for the best kelex/dnnsa ratio (4:1), but none of the three extractants alone extracts more than 43 pct of the ni under identical test conditions.
Paper in Solvent Extraction 1990, 1992, PP. 423-428