Preparation of nanometer ZnO with oxygen control byvacuum and behavior of impurity elements

Nanometer zinc oxide was prepared through oxygen control by vacuum using hot galvanizing dross as raw materials and air as an oxygen source,and the product purity is up to 99.98%.The influences of the reaction temperature and the vacuum degree of the reaction system on the morphologies of the product were investigated.The behavior of main impurity elements and their influence on the product quality were studied under different oxidation conditions.It is shown that the reaction temperature and the vacuum degree of the reaction system have great influence on the morphologies of the product.The product is mostly hexagonal wurtzite structure of nanometer tetrapod ZnO,the needles are slender,and the length-to-diameter ratio is large at suitable temperature and vacuum degree.The different behaviors of impurity Fe and Pb affect the product quality in different ways under different oxidation conditions.The joining of Fe into the product is mainly due to mechanical entrainment of zinc and the positive bias effect of Fe-Zn systems;however,Pb joins in the product because of its evaporation pressure and the positive bias effect of Pb-Zn systems.