CO/CH separation performance of SiO/PES composite membrane prepared by gas phase hydrolysis and grafting coating in gas-liquid membrane contactor: A comparative study.

The gas-liquid membrane contactor (GLMC) is a new and promising kind of gas separation technique, but still exhibits limitations, especially in membrane performance. In order to solve the above problems, we fabricated and characterized novel OH/SiO/PES composite membranes using gas phase hydrolysis and graft coating methods, respectively. In the preparation process, whether to use alkali to pretreat the membrane was used as an evaluation index. The CO/CH separation performance was tested using the modified OH/SiO/PES hollow fiber membrane as the membrane contactor in GLMC. In the experiment, we conducted a single factor experiment with diethanolamine (DEA) as the adsorbent to analyze the effect of the flow rate and concentration of DEA on the separation of CO/CH. The collected gas had a CH content of 99.92% and a CO flux of 10.1059 × 10 mol m s while DEA at a concentration of 1 mol/L was flowing at a rate of 16 L/h. The highest separation factor occurred at this moment, which was 833.67. Overall, the CO/CH separation performance in GLMC was enhanced with the use of the fluorinated OH/SiO/PES composite membrane.