C2H2 Absorption Using 1-Methyl-2-Pyrrlione Solution in a Hollow Fiber Membrane Contactor

Based on the principle of gas exchange in lung between environment and blood, microporous membrane as gas-liquid contactor was developed and successfully explored in gas absorption. The study is focused on the development of a membrane gas absorption process for C₂H₂ removal from coal pyrogenation by hydrogen plasma using 1-Methyl-2-Pyrrlione (NMP) solvent in combination with the more hydrophobic microporous polytetrafloroethylene (PTFE) hollow fiber membrane (pore diameter 0.22μm, pore volume 52%). The effects of C₂H₂ concentrations in the feed, gas feed flow rate, liquid flow rate and membrane module length on the mass transfer flux of C₂H₂ and absorption efficiency were investigated. The results showed that, with the increase in C₂H₂ concentration, gas feed flow rate and liquid flow rate, the mass transfer flux of C₂H₂ and absorption efficiency increased. The increase in module length resulted in a slight decrease in mass transfer flux of C₂H₂ and absorption efficiency. The highest C₂H₂ absorption efficiency was 99% for 8% of C₂H₂ in the feed at 30cm of module length. In addition, membrane absorption-desorption system composed of a membrane absorption unit and a hot regeneration unit was operated continuously for 114 h to investigate its duration performance. The results were that the absorption efficiency of C₂H₂ maintained at 90%, C₂H₂ concentration in desorption gas was 98.77% and PTFE membrane material presented excellent NMP absorbent stability.