Performance study of modified calcium magnesium acetate (MCMA) in the process of high temperature CO2 capture and the application of spent MCMA for sequential SO2 removal

Abstract

AbstractThe modified calcium magnesium acetate (MCMA) has the similar characteristics and properties to those of CMA and a lower production cost. In this study, the effect of temperature on the performance of MCMA in the cyclic calcination/carbonation reaction (CCCR) process was investigated. The pore structure characteristics of the spent MCMA particles were also studied. A tubular furnace reactor was used to study the sulfation reaction characteristics and kinetic characteristics of the spent MCMA after CCCR. The microstructure and the constituent elements of the spent MCMA after sulfation reaction were analyzed by the scanning electron microscopy (SEM) and the energy dispersive X‐ray spectrometry (EDS). The adsorption characteristics of MCMA were found similar to the analytically pure CMA in the CCCR process. The carbonation conversion of MCMA decreases significantly first and then varies little with increasing the cycle numbers. The sulfation process of all spent MCMA can be divided into two distinct stages including the chemical reaction‐controlled stage and the product layer diffusion‐controlled stage. The shrinking unreacted core model is appropriate to analyze the sulfation kinetic characteristics of the spent MCMA in the sulfation process. The sulfation conversions of the spent MCMA decrease gradually with increasing the cycle numbers of CCCR, while the MCMA‐30 (the modified CMA cycled 30 times in the CCCR process) still shows a sulfation conversion of 35.48%, indicating that the spent MCMA can be used as an ideal desulfurizer before the fresh sorbent serving as a CO2 carrier in the CCCR process. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.