膜气体吸收法分离混合气中的苯

摘要

In a self-made membrane gas absorption-vacuum membrane distillation combined process device, by using N-formylmorpholine (NFM) aqueous solution as absorbent and hydrophobic porous polypropylene hollow fiber membrane module (HEPPM) as the membrane contactor, the performance of membrane gas absorption process for separating C6H6/N2 gas mixture was studied. A comprehensive review of the inlet gas flow, gas mass concentration, flow of absorbent, absorbent, absorbent temperature and volume fraction of NFM absorbent load on separation efficiency was carried out. The experimental results show that benzene removal rate of52.8%−99.3% and the total volumetric mass transfer coefficient of 0.008−0.026 s−1 are achieved, under the conditions of the NFM volume fraction of 40%, imports of gas concentration of 3.6−9.6 mg/L, absorbent flow rate of15−75 mL/min, and inlet gas flow of 50−300 mL/min, indicating that the membrane gas absorption process for separating C6H6/N2 mixed gas has the advantages of high separation efficiency and high rate of mass transfer.%采用自行设计的膜气体吸收−减压膜蒸馏组合工艺装置，以N-甲酰吗啉(NFM)水溶液为吸收剂，疏水性多孔聚丙烯中空纤维膜组件(HEPPM)为膜接触器，研究膜气体吸收法分离C 6 H 6/N 2混合气性能，考察含苯废气流量、质量浓度，吸收剂流量、NFM体积分数、温度及负载对分离效果的影响。实验结果表明：在NFM 体积分数为40%，含苯废气质量浓度为3.6~9.6 mg/L，吸收剂流量为15~75 mL/min，含苯废气流量为50~300 mL/min条件下，苯的去除率为52.8%~99.3%，总体积传质系数为0.008~0.026 s−1；采用膜气体吸收法分离C6H6/N2混合气具有较高的分离效率和较快的传质速率。