High-temperature removal of cadmium compounds using solid sorbents

The use of solid sorbents to remove cadmium from incinerator flue gases was studied; the sorbents evaluated included alumina, kaolinite, lime, emathlite, and silica. Bauxite was discovered to be the most efficient Cd remover. In general, aluminum oxide-containing substances were found to be efficient Cd removers. The Cd sorption process apparently includes processes of condensation, adsorption, and diffusion. However, when the source of flue gas Cd is cadmium chloride, even efficient Cd removers such as bauxite and kaolinite are incapable of removing chlorine from flue gases.