SO2 Absorption Performance Enhancement by Ionic Liquid Supported on Mesoporous Molecular Sieve

TMGL (tetramethylguanidinium lactate) is believed to be a potential medium for SO2 removal. However, direct use of TMGL in SO2 absorption exhibits unsatisfactory absorption rate and desorption performance, mainly because of its hyperviscosity. In this work, mesoporous molecular sieve MCM-41 (mobil composition of matter no. 41) was employed as support material to prepare a novel absorbent (MCM-41-TMGL). The uptake of SO2 depends on TMGL, and the absorption rate depends on the porous feature of MCM-41-TMGL. Results show that MCM-41-TMGL dramatically improved the absorption kinetics and desorption efficiency, largely attributed to enhanced gasliquid interface. Moreover, the absorbed SO2 in MCM-41-TMGL can be easily stripped out by heating at 90 degrees C under vacuum, allowing MCM-41-TMGL-10% to maintain 95% of the initial absorption capacity after 10 cycles of regeneration. In addition, the absorption performance of MCM-41-TMGL was investigated under different conditions, including absorption temperature, SO2 concentration, and vapor concentration of simulated flue gas.