Cu-Zn-C3N4多孔结构催化剂制备及其催化CO2加氢合成甲醇反应性能研究
2020-08-24巩晓辉王明伞晓广
巩晓辉 王明 伞晓广



摘 要:采用静置沉淀结晶法构建一种新型的多孔海绵状Cu-Zn-C3N4催化剂应用于二氧化碳加氢制甲醇反应,并通过改变尿素的比例进行催化剂性能的对比。实验利用固定床反应器对催化剂进行性能评价,同时通过XRD、SEM、FI-IR等手段对催化剂进行表征,探讨催化剂的结构组成与催化剂性能之间的构效关系。实验结果表明:采用静置沉淀结晶法且尿素过量制备的Cu-Zn-C3N4催化剂呈现出海绵状多孔结构,提高了反应介质的传质传热效率。同时,嵌入在催化剂内部的C3N4能够活化二氧化碳,从而能够有效的提高催化剂的反应活性及选择性。
关 键 词:C3N4;二氧化碳加氢;甲醇合成;Cu-Zn-C3N4催化剂
中图分类号:TQ 426 文献标识码: A 文章编号: 1671-0460(2020)06-1103-04
Preparation of Cu-Zn-C3N4 Porous Catalyst and Its Catalytic Performance for Synthesis of Methanol by CO2 Hydrogenation Reaction
GONG Xiao-hui, WANG Ming, SAN Xiao-guang
(Shenyang University of Chemical Technology, Shenyang Liaoning 110142, China)
Abstract: A novel porous sponge-like Cu-Zn-C3N4 catalyst was prepared by static precipitation crystallization, and it was applied in the reaction of carbon dioxide hydrogenation to methanol. The performance of the catalyst was compared by changing the ratio of urea. The performance of the catalyst was evaluated by fixed bed reactor. The catalyst was characterized by XRD, SEM and FI-IR. The structure-activity relationship between the structure of the catalyst and the performance of the catalyst was discussed. The experimental results showed that the Cu-Zn-C3N4 catalyst prepared by static precipitation crystallization with excess urea exhibited sponge-like porous structure, which improved the mass transfer and heat transfer efficiency of the reaction medium. At the same time, C3N4 embedded in the catalyst could activate carbon dioxide, which effectively improved the reactivity and selectivity of the catalyst.
Key words: C3N4; Carbon dioxide hydrogenation; Methanol synthesis; Cu-Zn-C3N4 catalyst
近幾年,化石燃料的消化量正以惊人的速度持续增长,虽然这种激增的需求推动了社会的进步,但二氧化碳的大量排放导致了温室效应、全球变
暖[1],从而引发了一系列环境问题,比如冰川融化、海平面上升等,这些问题直接威胁着人类赖于生存的自然生态环境同时也引起了全球化工以及环保等领域工作者的密切关注[2-3]。因此,CO2减排与利用的问题迫在眉睫,开发高效的二氧化碳利用技术显得至为关键[4]。而CO2化学转化是降低大气中CO2含量的有效方法[5]。目前,二氧化碳催化加氢转化成为液体燃料引起研究者的广泛关注,被认为是一种理想的二氧化碳循环利用路线。二氧化碳作为一种无毒、安全、廉价的碳一化学原料,可在不同的催化剂作用下催化加氢生成甲烷[6]、甲醇[7]、二甲 醚[8]以及碳氢化合物。……
