Grushevenko Evgenia, Balynin Alexey, Ashimov Ruslan, Sokolov Stepan, Legkov Sergey, Bondarenko Galina, Borisov Ilya, Sadeghi Morteza, Bazhenov Stepan, Volkov Alexey
A.V. Topchiev Institute of Petrochemical Synthesis RAS, 119991 Moscow, Russia.
Department of Gas Chemistry, Faculty of Chemical Technology and Ecology, National University of Oil and Gas "Gubkin University", 119991 Moscow, Russia.
Polymers (Basel). 2022 Apr 18;14(8):1625. doi: 10.3390/polym14081625.
The application of gas-liquid membrane contactors for ethane-ethylene separation seems to offer a good alternative to conventional energy-intensive processes. This work aims to develop new hydrophobic composite membranes with active ethylene carriers and to demonstrate their potential for ethylene/ethane separation in gas-liquid membrane contactors. For the first time, hybrid membrane materials based on polyoctylmethylsiloxane (POMS) and silver tetrafluoroborate, with a Si:Ag ratio of 10:0.11 and 10:2.2, have been obtained. This technique allowed us to obtain POMS-based membranes with silver nanoparticles (8 nm), which are dispersed in the polymer matrix. The dispersion of silver in the POMS matrix is confirmed by the data IR-spectroscopy, wide-angle X-ray diffraction, and X-ray fluorescence analyses. These membranes combine the hydrophobicity of POMS and the selectivity of silver ions toward ethylene. It was shown that ethylene sorption at 600 mbar rises from 0.89 cm(STP)/g to 3.212 cm(STP)/g with an increase of Ag content in POMS from 0 to 9 wt%. Moreover, the membrane acquires an increased sorption affinity for ethylene. The ethylene/ethane sorption selectivity of POMS is 0.64; for the membrane with 9 wt% silver nanoparticles, the ethylene/ethane sorption selectivity was 2.46. Based on the hybrid material, POMS-Ag, composite membranes were developed on a polyvinylidene fluoride (PVDF) porous support, with a selective layer thickness of 5-10 µm. The transport properties of the membranes were studied by separating a binary mixture of ethylene/ethane at 20/80% vol. It has been shown that the addition of silver nanoparticles to the POMS matrix leads to a decrease in the ethylene permeability, but ethylene/ethane selectivity increases from 0.9 (POMS) to 1.3 (9 wt% Ag). It was noted that when the POMS-Ag membrane is exposed to the gas mixture flow for 3 h, the selectivity increases to 1.3 (0.5 wt% Ag) and 2.3 (9 wt% Ag) due to an increase in ethylene permeability. Testing of the obtained membranes in a gas-liquid contactor showed that the introduction of silver into the POMS matrix makes it possible to intensify the process of ethylene mass transfer by more than 1.5 times.
气液膜接触器在乙烷 - 乙烯分离中的应用似乎为传统的高能耗工艺提供了一个很好的替代方案。这项工作旨在开发具有活性乙烯载体的新型疏水复合膜，并展示其在气液膜接触器中进行乙烯/乙烷分离的潜力。首次获得了基于聚辛基甲基硅氧烷（POMS）和四氟硼酸银的混合膜材料，硅与银的比例为10:0.11和10:2.2。该技术使我们能够获得含有分散在聚合物基质中的银纳米颗粒（8纳米）的基于POMS的膜。红外光谱、广角X射线衍射和X射线荧光分析的数据证实了银在POMS基质中的分散情况。这些膜结合了POMS的疏水性和银离子对乙烯的选择性。结果表明，随着POMS中银含量从0增加到9 wt%，在600毫巴下乙烯的吸附量从0.89厘米（标准温度和压力）/克增加到3.212厘米（标准温度和压力）/克。此外，该膜对乙烯的吸附亲和力增加。POMS的乙烯/乙烷吸附选择性为0.64；对于含有9 wt%银纳米颗粒的膜，乙烯/乙烷吸附选择性为2.46。基于混合材料POMS - Ag，在聚偏二氟乙烯（PVDF）多孔支撑体上制备了复合膜，选择性层厚度为5 - 10微米。通过分离体积比为20/80%的乙烯/乙烷二元混合物来研究膜的传输性能。结果表明，向POMS基质中添加银纳米颗粒会导致乙烯渗透率降低，但乙烯/乙烷选择性从0.9（POMS）增加到1.3（9 wt%银）。值得注意的是，当POMS - Ag膜暴露于气体混合物流中3小时后，由于乙烯渗透率的增加，选择性分别增加到1.3（0.5 wt%银）和2.3（9 wt%银）。在气液接触器中对所得膜进行测试表明，将银引入POMS基质可以使乙烯传质过程强化超过1.5倍。
