Synthesis and characterization of low-carbon cementitious materials from suspended calcined coal gangue

Coal gangue is used to replace cement clinker prepare cementitious material via activation techniques. Thus, the solid waste can be effectively disposed, and carbon emission from production processes significantly reduced. In this paper, product transformation, reaction mechanism, thermal kinetics of coal were analyzed by X-ray diffraction, analysis, infrared scanning electron microscopy. We employed a suspension calcination process high-activity metakaolin. A was prepared metakaolin cement, mechanical properties hydration products analyzed. The results show that formed dehydroxylation kaolinite in during calcination, based on Z–L–T three-dimensional diffusion mechanism with an energy 190.2 kJ/mol. Metakaolin dissolution rates 69.5%–76.3% 44.5%–52.3% activated alumina silica, respectively, synthesized calcining at 750°C–850°C for approximately 5 s calcination. showed 28-days compressive strength 57.5–61.5 MPa activity index 114%–135%. participated structurally dense hardened body, which resulted high replacement volume specimens. preparation low-carbon materials activating provides basis utilization reduction emissions production.