Purification method and application of secondary zinc oxide

Abstract

The invention relates to a purification method of secondary zinc oxide. The purification method comprises the following specific steps of adding industrial sulphuric acid in soot containing secondaryzinc oxide, conducting granulating by a granulating device, and roasting particles in a rotary kiln for 3-5h at 600-800 DEG C. The application of secondary zinc oxide comprises the following specificsteps of adding 3-5 times of volume of electrolyte residue into the purified secondary zinc oxide for leaching, controlling the pH of a leaching terminal point at 3.3-4.1 by supplementing industrial sulphuric acid, conducting leaching for 4-5h, and conducting filtering separation to obtain leach liquor; adding hydrogen peroxide and lime milk in the leach liquor, controlling the pH at 5.0 and the temperature at 45-65 DEG C, and maintaining for 1-2h, and conducting filtering; and adding CuOH and Ni(OH)2 in the leach liquor, controlling the pH at 2.5-4.8 and the temperature at 35-50 DEG C, maintaining for 1h, conducting filtering, and thus obtaining pure electrolyte. The purification method has the advantages of unobstructed process, less consumption, low cost, no three wastes and environment-friendly property.

Description

technical field [0001] The invention relates to the technical field of metallurgy and chemical industry, in particular to a method for purifying secondary zinc oxide and its application. Background technique [0002] Zinc oxide powder is obtained by treating solid waste containing zinc (such as iron and steel dust, lead smelting slag, etc.) by high-temperature fuming method, which is a secondary resource for producing zinc metal. There are some impurities in its chemical composition which are very harmful to zinc production by wet method, such as Cl and F. It is impossible to effectively remove the fluorine and chlorine impurities with such a high content by using the conventional multi-hearth furnace or rotary kiln heating and roasting method to process zinc oxide powder; the zinc oxide powder is pretreated by alkali washing, and then combined with zinc sulfate leaching solution in wet method The combined method of dechlorination has disadvantages such as lengthy process, ...

AI Technical Summary

Problems solved by technology

It is impossible to effectively remove the fluorine and chlorine impurities with such a high content by using the conventional multi-hearth furnace or rotary kiln heating and roasting method to process zinc oxide powder; the zinc oxide powder is pretreated by alkali washing, and then combined with zinc sulfate leaching solution in wet method The combined method of dechlorination has disadvantages such as lengthy process, large loss of zinc, high treatment cost, and complicated sewage treatment.