Alane, Nadia University of Annaba - Department of Chemical Engineering, Algeria , Djerad, Souad , University of Annaba - Department of Chemical Engineering, Algeria , Tifouti, Lakhdar University of Annaba - Department of Chemical Engineering, Algeria

ACID LEACHING OF ZINC FROM ZNO/AL2 O3 CATALYST

34209

In this study a simple process has been developed for zinc recovery from ZnO/Al2 O3 catalyst in acidic milieu. The results have shown that a high dissolution efficiency of zinc was achieved with H2SO4 (2M) at ambient temperature with a liquid/solid ratio of 10/1 while alumina support was left unaffected. The dissolution of ZnO reached 81% in the first 4 hours.The rate of dissolution increased slowly after that and reached 90% after 24h. Leaching process was found to be controlled by diffusion through a product layer. After separation,alumina with high purity (99,5%) was obtained. Zinc was precipitated in leach liquor by pH-controlled precipitation using sodium hydroxide. The resulting solid was purified and dried at120°C. Zinc powder in the form of ZnO with 100% purity was produced with recovery efficiency of 72,2%.

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zinc recovery , acid leaching , separation , alpha alumina , caustic precipitation

Lebanese Science Journal

74