Selective removal of H₂S from high concentration CO₂ by catalytic wet oxidation in microporous tube-in-tube microchannel reactor

Selective removal of H₂S over CO₂ using a novel alkali solution is accomplished out in a microporous tube-in-tube microchannel reactor (MTMCR). H₂S is almost stripped from gas streams by wet catalytic oxidation using Na₂CO₃ + NaHCO₃ absorbent with 888 catalyst. The effects of alkalinity of the absorbent, NaHCO₃ content in solution, gas–liquid ratio, catalyst concentration and temperature on desulfurization efficiency and selectivity were investigated. According to the experimental results, the alkalinity of the absorbent, catalyst concentration and gas–liquid ratio exhibited a significant effect on the removal efficiency and selectivity of H₂S. The removal efficiency and selectivity of H₂S are 99.19% and 32, respectively, for the MTMCR with an average micropore size of 40 μm, an annular channel width of 250 μm and an annular channel length of 233 mm at a gas flow rate of 300 L/h, gas–liquid ratio of 40, alkalinity of 0.25 N, NaHCO₃ content of 0.8, catalyst concentration of 20ppm and temperature of 323 K. MTMCR has the advantage of high selectivity, efficiency and low absorption liquid consumption.