文献类型：期刊文献

英文题名：Introducing of Cu(I) in MOFs by In Situ Reduction with Ni as the Catalyst for Efficient Olefin/Paraffin Separation

作者：Qian, Jiayu[1];Pu, Xin[1];Liu, Qiaona[1];Zhou, Xiaoyu[1];Han, Xin[1];Ye, Lei[1];Qin, Xinglong[1];Liu, Jichang[1,2]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China;[2]Shihezi Univ, Sch Chem & Chem Engn, State Key Lab Incubat Base Green Proc Chem Engn, Shihezi 832003, Xinjiang, Peoples R China

年份：2023

卷号：39

期号：49

起止页码：18022

外文期刊名：LANGMUIR

收录：;EI(收录号：20235015216630);WOS:【SCI-EXPANDED(收录号:WOS:001124694700001)】；

语种：英文

外文关键词：Adsorption - Catalysts - Copper compounds - Heavy ions - Hexane - Molecules - Nickel - Paraffins - Porous materials

摘要：Olefins can be cracked to provide more low-carbon olefins than paraffins; therefore, separation of olefin/paraffin mixtures is essential for arranging hydrocarbon molecules for directed conversion. In this article, a simple approach for reducing copper atoms in Cu-BTC has been developed to improve olefin/paraffin adsorption capacity and selectivity. Considering that Cu-BTC shows adsorption benefits, its olefin/paraffin adsorption and separation performance were improved further by in situ reduction of Cu(II) to Cu(I) in Cu-BTC using ethanol as the reducing agent and nickel ions as the catalyst. The results revealed that during the reduction process, Cu ion conversion from tetra-ligand to diligand considerably increased their specific surface area, resulting in more active adsorption sites inside the modified sample. The ratio of Cu(I)/Cu(II) in the modified samples varied from 0.57 to 0.96. When Cu(II) of Cu-BTC was reduced to Cu(I), the adsorption capacities of 1-hexene increased from 145.97 to 243.65 mg/g, whereas n-hexane adsorption increased only slightly from 8.18 to 11.43 mg/g, resulting in an acceptable increase in selectivity from 17.84 to 21.32. Cu-BTC, due to its own Cu atoms, minimizes the substantial requirements for the synthesis process as well as the oxygen avoidance conditions for storage when monovalent copper is introduced, compared to other porous materials. Experimental results found that when Cu(I) was introduced, the Lewis acidic sites of the modified Cu-BTC material were increased, and Cu(I) has an electrical structure that makes it susceptible to both accepting and donating too many d electrons, resulting in a stronger adsorption of olefins containing pi-electrons to them. Materials Studio simulation revealed that the isosteric heats of modified Cu-BTC increased by 2.7 kJ/mol, indicating that it has a stronger adsorption capacity for olefins.