Processing of solutions containing nickel and ammonium sulphate through solvent extraction using PC-88A

A process was developed to obtain a concentrated nickel sulphate:solution f rom a nickel-containing: cobalt raffinate using PC-88A as the extractant. M ore than 99% nickel extraction was achieved in three stages with I hi PC-88 A neutralised to 50% at an organic to aqueous ratio of 2.2. Nickel was stri pped from loaded organic in two counter-current stages at the O:A ratio of 5 with 82 kg/m(3) of H2SO4 to obtain a strip solution containing about 55 k g/m(3) nickel (similar to pH 3.0). The spent organic contained 2.2 g/m(3) n ickel corresponding to a degree of stripping > 99.98%. The nickel sulphate solution obtained is suitable for further processing to obtain nickel metal or a nickel salt. (C) 1999 Elsevier Science B.V. All rights reserved.