Removal of Copper from Acidic Nickel Chloride Solution with Nickel Matte

摘要

Removal of copper from acidic nickel chloride solution was investigated using nickel matte with different compositions in various conditions. The following results were obtained.1) Cupric ion in the solution is reduced to cuprous ion by metallic nickel or Ni_3S_2 in matte at the early stage after addition of nickel matte into the solution. Consequently metallic copper or copper sulfide Cu_2S is formed by the reaction with the matte.2) Copper is removed as metallic copper when the solution is reduced to below-50 mV of oxidation-reduction potential, while as Cu_2S above 150 mV.3) These types of copper removed from the solution change according to the R value, defined as ratio of content of metallic nickel and Ni_3S_2 to amount of copper ion in the solution.4) The reaction for metallic copper formation is faster than that for the formation of Cu_2S. The difference between the reaction constants for both reactions at 75 deg C, is approximately ten times.5) Copper is removed to a lower concentration with addition of both matte and elemental sulfur.