Synthesis of [C12mim]FeCl4 and study of the swelling effect on coal and the kinetics of pyrolysis

Abstract

One of the effective approaches to tackle Chinese energy concerns is to employ direct coal liquefaction technology to make liquid fuels. The investigation of [C12mim]FeCl4 synthesis, modification of coal swelling and pyrolysis influence the economic and environmental benefits of direct coal liquefaction. The DSC and Dmol3 detection methods were used to determine that FeCl4− is the most stable anion group in the magnetic ionic liquid system, Raman, FT-IR and EDS detection was utilized to confirm this. Second, [C12mim]FeCl4 was used to swell low-rank coal (LRC). With time, magnetic ionic liquid (MIL) causes more harm to the overall structure and surface morphology of coal samples, as seen by SEM and EDS. As revealed by TGA, the effect of magnetic ionic liquid swelling on the pyrolysis characteristics of coal samples has a facilitating effect, with the 24 h modification effect being the most substantial, the weight lost was increased by 5.8423%. According to the Coats-Redfern approach of pyrolysis kinetics, the pyrolysis processes of coal samples were compatible with secondary reaction kinetics in low temperature segment, while tertiary and quaternary reaction kinetics were adequate in high temperature segment. The activation energy of pyrolysis of coal samples was considerably reduced by the magnetic ionic liquid swelling of coal samples. Through salting-out-recovery experiments, it is proved that MIL in aqueous solution can be recovered.