Fabrication of microstructured Mg5(CO3)4(OH)2·4H2O and MgCO3 in flue gas absorption technology

Abstract

Basic magnesium carbonate/magnesium carbonate microstructured materials have been synthesized as by-products in a simulative flue gas absorption technology through a direct carbonation of Mg-based (brucite) slurry. A probable carbonation mechanism from brucite to magnesite is proposed via a couple of gas–solid reaction pathways. Experimental results demonstrate that the reactions undergo transitional basic magnesium carbonate carnations constructed by microflakes and then development of rhombohedral magnesium carbonate microstructured crystals with further incorporation of carbon dioxide. Furthermore, the carbonation parameters of brucite are also studied in detail. Since the novel approach is simple and has a high additional value in combination with the flue gas absorption technology, the process could bring significant progress for residue treatment in chemical CO2 capture.