Li Liangying, Guo Lidong, Zheng Fang, Zhang Zhiguo, Yang Qiwei, Yang Yiwen, Ren Qilong, Bao Zongbi
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, P. R. China.
Institute of Zhejiang University-Quzhou, Quzhou 324000, P. R. China.
ACS Appl Mater Interfaces. 2020 Apr 8;12(14):17147-17154. doi: 10.1021/acsami.0c03139. Epub 2020 Mar 25.
The simultaneous capture of trace propyne and propadiene from propylene is one of the important but energy demanding industrial processes because of their similar physicochemical properties as well as the ultralow concentration in the mixtures. Herein, a highly stable Ca-based MOF, constructed from an inexpensive precursor (CaCO) and rigid squaric acid, is capable of preferentially capturing trace propyne and propadiene with record-high uptake capacities of 2.44 and 2.64 mmol/g at pressures as low as 5 mbar, respectively. Direct multicomponent breakthrough experiments confirm that Ca-based MOF exhibits an excellent performance for simultaneous removal of trace propyne and propadiene from propylene. DFT simulation and single-crystal X-ray diffraction of propadiene- and propyne-adsorbed Ca-based MOFs reveal that the strong affinity of the framework toward two species is ascribed to the multiple types of cooperative binding including π-π stacking and C-H···O interactions. The calcium squarate framework sets a new benchmark for adsorptive purification of propylene, showing great potential in the practical application.
由于丙烯中痕量丙炔和丙二烯的物理化学性质相似且混合物中浓度极低，从丙烯中同时捕获痕量丙炔和丙二烯是重要但耗能的工业过程之一。在此，一种由廉价前驱体（CaCO）和刚性方酸构建的高度稳定的钙基金属有机框架（MOF），能够在低至5毫巴的压力下分别以创纪录的2.44和2.64 mmol/g的高吸附容量优先捕获痕量丙炔和丙二烯。直接多组分穿透实验证实，钙基金属有机框架在从丙烯中同时去除痕量丙炔和丙二烯方面表现出优异性能。对吸附丙二烯和丙炔的钙基金属有机框架进行的密度泛函理论（DFT）模拟和单晶X射线衍射表明，框架对这两种物质的强亲和力归因于包括π-π堆积和C-H···O相互作用在内的多种协同结合类型。方酸钙框架为丙烯的吸附净化树立了新的标杆，在实际应用中显示出巨大潜力。
