Multi-functional sorbents for the simultaneous removal of sulfur and lead compounds from hot flue gases

Abstract

A multi-functional sorbent is developed for the simultaneous removal of PbCl 2 vapor and sulfur dioxide from the combustion gases. The sorbent is tested in a bench-scale reactor at the temperature of 700 °C, using simulated flue gas (SFG) containing controlled amounts of PbCl 2 and SO 2 compounds. The removal characteristics of PbCl 2 and SO 2, individually and in combination, are investigated. The results show that the mechanism of capture by the sorbent is not a simple physical adsorption process but seems to involve a chemical reaction between the Ca-based sorbent and the contaminants from the simulated flue gas. The porous product layer in the case of individual SO 2 sorption is in a molten state at the reaction temperature. In contrast, the combined sorption of lead and sulfur compounds generates a flower-shaped polycrystalline product layer.