Thermodynamic Simulation of the Interaction Reaction between Copper-Based Oxygen Carrier and Acid Gases from Municipal Solid Waste Pyrolysis

Abstract

To reveal the interaction reaction of copper-based oxygen carriers with acid gases during chemical looping with oxygen uncoupling of MSW pyrolysis and gasification syngas, the thermodynamic analysis is employed by HSC Chemistry. The thermodynamic simulation results show that the products of the copper-chloride interactions are solid CuCl, gaseous Cu3Cl3 (g), and CuCl (g), and no solid CuCl2 is formed. In addition, it’s found that CuCl (g) originates from the high-temperature decomposition of the complex Cu3Cl3 (g). At a sufficient amount of OC, the interaction products of copper-based OC with H2S are CuSO4, SO2, and Cu2SO4, while Cu2S and CuS disappear. Compared to HCl, H2S dominates during the competitive reaction or adsorption with copper-based oxygen carrier or CaO. Due to the capture of Cl and S in the gaseous state of Ca2+, the lattice oxygen of chlorinated or sulfated oxygen carriers can be restored, suggesting that CaO can be used as an in situ dechlorinator for CLOU. The results of this work will provide theoretical guidance for the inhibition of copper-based oxygen carriers chlorination loss and active design of multifunctional oxygen carriers.