Treatment method of chlorine-containing zinc oxide secondary material

A treatment method of a chlorine-containing zinc oxide secondary material, wherein, the method comprises the following steps:

• (1) leaching a chlorine-containing zinc oxide secondary material I with an acidic solution to obtain a leaching liquor and a leaching residue;
• (2) selectively extracting zinc from the leaching liquor obtained from step (1) with a di-(2-ethylhexyl)phosphoric acid—kerosene solvent to obtain a zinc-containing organic phase as well as a chlorine and acid containing raffinate;
• (3) recovering zinc from the zinc-containing organic phase obtained from step (2) by stripping and electrolysis and returning the organic phase after the stripping to step (2) to extract zinc;
• (4) taking the chlorine and acid containing raffinate obtained from step (2) as the acidic solution of step (1), returning to step (1) and repeating steps (1)-(4);
• (5) taking out the chlorine and acid containing raffinate obtained from step (4) when chlorine ion of a chlorine-containing aqueous phase in step (2) achieves 50-80 g/L after circulating and repeating steps (1)-(4), wherein the chlorine content of the chlorine and acid containing raffinate taken out is identical to the chlorine content of a chlorine-containing zinc oxide secondary material I added in step (1) so as to keep a balance between an amount of chlorine ion added and an amount of chlorine ion taken out;
• mixing the chlorine and acid containing raffinate taken out with an additional chlorine-containing zinc oxide secondary material H at liquid-solid ratio of 1-3:1;
• carrying out liquid-solid separation to obtain a separated deposit;
• returning the separated deposit to step (1) for leaching with the acidic solution;
• (6) removing impurities of the chlorine-containing aqueous phase to obtain a solution containing KCl and NaCl when step (5) is completed and the solution contains 80-120 g/L of chlorine ion and 160-240 g/L of total salt content;
• and
• (7) evaporating and concentrating the solution containing KCl and NaCl obtained from step (6) to produce KCl and NaCl products by crystallization.