The production of Zn from ZnO in a high-temperature solar decomposition quench process - I. The scientific framework for the process

We present a theoretical and experimental study of a solar decomposition process for producing Zn and O-2 from ZnO(s). The decomposition step occurs at temperatures near 2000 K, and the gaseous products are quenched. A numerical model that uses the latest kinetic data for the decomposition and reoxidation reactions suggests that Zn conversions as high as 80% can be obtained with solar flux densities of 2 MW m(-2). The decomposition and quench were effected in a solar furnace and in a solar furnace simulator. Zn yields were as high as 90% depending in part on the dilution ratio and quenching surface's temperature. (C) 1998 Elsevier Science Ltd. All rights reserved.