Schuldt Karina, Lillepärg Jelena, Pohlmann Jan, Brinkmann Torsten, Shishatskiy Sergey
Helmholtz-Zentrum Hereon, Institute of Membrane Research, Max-Planck-Str. 1, 21502 Geesthacht, Germany.
Camfil GmbH, Feldstraße 26-32, 23585 Reinfeld, Germany.
Membranes (Basel). 2024 Mar 6;14(3):66. doi: 10.3390/membranes14030066.
The gas transport properties of thin film composite membranes (TFCMs) with selective layers of PolyActive™, polydimethylsiloxane (PDMS), and polyoctylmethylsiloxane (POMS) were investigated over a range of temperatures (10-34 °C; temperature increments of 2 °C) and pressures (1-65 bar abs; 38 pressure increments). The variation in the feed pressure of condensable gases CO and CH enabled the observation of peaks of permeance in dependence on the feed pressure and temperature. For PDMS and POMS, the permeance peak was reproduced at the same feed gas activity as when the feed temperature was changed. PolyActive™ TFCM showed a more complex behaviour, most probably due to a higher CO affinity towards the poly(ethylene glycol) domains of this block copolymer. A significant decrease in the permeate temperature associated with the Joule-Thomson effect was observed for all TFCMs. The stepwise permeance drop was observed at a feed gas activity of p/po ≥ 1, clearly indicating that a penetrant transfer through the selective layer occurs only according to the conditions on the feed side of the membrane. The permeate side gas temperature has no influence on the state of the selective layer or penetrant diffusing through it. The most likely cause of the observed TFCM behaviour is capillary condensation of the penetrant in the swollen selective layer material, which can be provoked by the clustering of penetrant molecules.
研究了具有聚活性™、聚二甲基硅氧烷（PDMS）和聚辛基甲基硅氧烷（POMS）选择性层的薄膜复合膜（TFCM）在一系列温度（10 - 34°C；温度增量为2°C）和压力（1 - 65 bar绝对压力；38个压力增量）下的气体传输特性。可冷凝气体CO和CH进料压力的变化使得能够观察到渗透率峰值与进料压力和温度的依赖关系。对于PDMS和POMS，在进料温度变化时，在相同的进料气体活度下重现了渗透率峰值。聚活性™ TFCM表现出更复杂的行为，很可能是由于CO对这种嵌段共聚物的聚（乙二醇）域具有更高的亲和力。对于所有TFCM，均观察到与焦耳 - 汤姆逊效应相关的渗透物温度显著下降。在进料气体活度p/po≥1时观察到渗透率的逐步下降，清楚地表明渗透物仅根据膜进料侧的条件通过选择性层进行传输。渗透侧气体温度对选择性层的状态或通过它扩散的渗透物没有影响。观察到的TFCM行为最可能的原因是渗透物在溶胀的选择性层材料中发生毛细管冷凝，这可能是由渗透物分子的聚集引起的。
