A new catalytic opportunity for waste materials: Application of waste slag based catalyst in CO2 fixation reaction

Iron and steel industry is one of the most energy-intensive industries, consuming 5-6% of the world's total energy consumption and emitting 5-7% of total world CO2 gas emissions. Large volume of CO2 emitted from iron and steel industry makes a significant contribution to global warming and climate change. Blast furnace slag (BFS), a high volume mineral waste discharged from iron and steel making processes, can potentially be used as an abundant and low-cost precursor for synthesizing active materials of catalytic interest that utilize the emitted CO2 in synthetic chemistry. In this study, we demonstrate that a Ca-based layered double hydroxide (LDH) compound can be synthesized from BFS through a facile synthetic procedure, and the thus synthesized material acts as a solid base catalyst that efficiently catalyzes the cycloaddition reaction of epoxides with atmospheric pressure of CO2 to give five-membered cyclic carbonates. The strategy proposed in this study would be one of the possible approaches that contribute to both efficient utilization of CO2 and waste management problems lying in iron and steel industry. (C) 2013 Elsevier Ltd. All rights reserved.