| 摘要 |
<p>PURPOSE:To economically recover nickel in the form of an aqueous solution, by successively blowing air and then chlorine into a slurry containing nickel sulfide and proper concentrations of sulfuric acid and chlorine ions so that proper redox potential is obtained. CONSTITUTION:At the time of carrying out electrolytic refining of metal nickel by using nickel matte as an anode, slimes formed at the anode or the residue obtained by removing a part of simple-substance sulfur content from the above is formed into a slurry of about 200-300g/l. Further, >=70g/l, preferably about 80-250g/l, of sulfuric acid and >=10g/l, preferably about 35-50g/l, of chlorine ion from NaCl, etc., are incorporated to the above aqueous solution. The above aqueous solution is maintained in a heated state of about 80-100 deg.C, into which air or oxygen-enriched air is blown until redox potential comes to >=550mV. Then, chlorine is blown into the above slurry in the same heated state as mentioned above so that redox potential comes to 650-750mV. In this way, nickel can be economically recovered in the form of an aqueous solution from nickel sulfide in the slimes or the residue.</p> |
