Experimental investigations on the crystallization of zinc by direct irradiation of zinc oxide in a solar furnace

Concentrated solar irradiation was used to thermally dissociate ZnO and to study the zinc vapor condensation process in the presence of oxygen under s everal dilution, temperature, pressure, and irradiation conditions. Product samples were taken from targets on the condenser surface and were analyzed with X-ray diffractometry and scanning electron microscopy, The zinc oxide formation by reoxidation of zinc was found to be of a heterogeneous nature , with homogeneously condensed zinc serving as the main nucleation sites. H igh zinc yields were obtained under conditions which favor supersaturation of zinc vapor and high deposition rates of zinc, whereby separation of cond ensing zinc and oxygen is desired.