RECLAIMING OF ZINC ASH AS ZINCITE AND LAYERED DOUBLE HYDROXIDE

One of the so called "dirty industry" is represented by hot-dip galvanizing process. The most important waste resulted from this process, from quantitative point of view, is zinc ash that contains a mixture of metallic zinc and zinc oxide with a total content of zinc between 70-90%. The recovery methods of zinc consist in the conversion of zinc ash into zinc oxide, that can be purified to obtain a product which can be used in the cosmetic industry. The aim of this work is the study of zinc ash reclaiming as zincite followed by synthesis of layered double hydroxide. The method consists in acid solubilization of zinc ash with sulfuric acid, the purification of obtained solution followed by solidification of products for zincite production. The obtained zincite is dissolved in acid solution and the layered double hydroxide is synthesized by co-precipitation with aluminum salt in alkaline media. The obtained layered double hydroxide was characterized by morphological and structural point of view. In order to demonstrate the capability of this material to act as adsorbent, studies about the equilibrium of phenol adsorption from aqueous solutions were carried out.