High‐performance molecular‐separation ceramic membranes derived from oxidative cross‐linked polytitanocarbosilane
High‐performance molecular‐separation ceramic membranes derived from oxidative cross‐linked polytitanocarbosilane
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DOI：
10.1111/jace.17108
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发表时间：
2020-08
影响因子：
3.9
通讯作者：
Qing Wang;Liang Yu;Hiroki Nagasawa;M. Kanezashi;T. Tsuru
中科院分区：
文献类型：
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作者：
Qing Wang;Liang Yu;Hiroki Nagasawa;M. Kanezashi;T. Tsuru
采用预陶化聚合物制备了聚钛碳硅烷(TiPCS)衍生陶瓷膜。重点研究了一种用于诱导交联的热氧化固化工艺以及该工艺对TiPCS陶瓷产率、热稳定性、抗氧化性和微观结构的影响。交联型TiPCS粉末的陶瓷产率和热稳定性均高于未交联型TiPCS粉末。此外，具有均匀微孔的交联型TiPCS表现出比未交联型TiPCS更高的N2和CO2吸附容量、BET比表面积和微孔体积，并且交联型TiPCS在高温下提高了孔结构的稳定性。与未交联膜相比，经交联的TiPCS膜具有较高的H_2透过率(1.49g×10~(-6)−/(m~2·m~2·pA))和亚纳米孔(H_2/SF_6选择性：12~000，H_2/N_2：10)，并且具有更高的抗氧化性能。此外，对TiPCS前驱体涂层溶液浓度的影响进行了优化，并对膜的高温水热稳定性进行了评价。优化后的膜在甲醇/乙酸丁酯或甲醇/甲苯的二元共沸体系中表现出了良好的渗透汽化脱除甲醇的性能，并表现出较高的水热稳定性和良好的高温除湿性能。
Polytitanocarbosilane (TiPCS)‐derived ceramic membranes were fabricated using a pre‐ceramic polymer. Special attention was focused on a process of thermal‐oxidative curing that was used to induce cross‐linking and the effect of this process on the ceramic yield, thermal stability, oxidation resistance, and microstructure of TiPCS. The cross‐linked TiPCS powders showed a ceramic yield and thermal stability that were higher than that from the non‐cross‐linked version. In addition, the cross‐linked TiPCS with uniform micropores showed higher levels of N2and CO2adsorption capacity, BET surface area, and micropore volume than the non‐cross‐linked versions, and the cross‐linking process enhanced the stability of the pore structure at high temperature. The cross‐linked TiPCS membranes showed high H2permeance (1.49 × 10−6mol/(m2s Pa)) with sub‐nanopores (H2/SF6selectivity: 12 000, H2/N2: 10), and in addition higher oxidation resistance than their non‐cross‐linked counterparts. Furthermore, the influence of the concentration of the TiPCS precursor coating solution was optimized and the hydrothermal stability of the membranes at high temperatures was also evaluated. The optimized membrane demonstrated great performance for the pervaporation removal of methanol in binary azeotropic systems of either MeOH/butyl acetate or MeOH/toluene, and it also showed high hydrothermal stability with excellent dehumidification performance under high temperatures.