聚二甲基硅氧烷/聚醚酰亚胺平板复合膜CO2/CH4的研究

利用聚二甲基硅氧烷/聚醚酰亚胺（PDMS/PEI）非对称平板复合膜，以CO2/CH4混合体系作为研究对象，考察了原料气组成、原料气压力、渗余相流量、温度对分离过程的影响。结果表明：随着原料气中CH4组成的提高，CO2渗透速率下降，分离因子先升高，但在CH4体积分数大于0.5时，分离因子开始下降；随着原料气压力的提高，CO2的渗透速率和分离因子均为下降趋势；在不同压力和温度下，随着渗余相流量的增大，CO2渗透速率基本维持稳定，分离因子略有上升，其中在低压或者低温下，CO2分离因子变化不大，在高压或者高温下，CO2分离因子上升明显。

Separation of carbon dioxide and methane through a poly (dimethyl siloxane)/asymmetric polyetherimide (PDMS/PEI) membrane

This paper describes the removal of carbon dioxide from methane by a membrane of the rubbery polymer poly(dimethylsiloxane)/asymmetric polyetherimide (PDMS/PEI). The effects of varying the operating conditions (feed fraction, feed pressure, residue flow rate and temperature) on the separation process were studied. With increasing methane concentration the permeation rate decreased, whilst the separation factor initially increased with increasing methane concentration and then decreased when the methane volume fraction exceeded 0.5. The permeation rate and separation factor decreased with increasing feed pressure. At different pressures and temperatures, the permeation rate was stable with increasing residue flow rate, while the separation factor changed a little at low pressures or low temperatures, but changed more markedly at high pressures or temperatures.