文献类型：期刊文献

中文题名：甲醇无氧脱氢制甲醛Cu催化剂的粒径效应

英文题名：Effect of Cu catalyst particle size on methanol nonoxidative dehydrogenation to formaldehyde

作者：左骥[1];罗莉[1];谢永锴[1];陈文尧[1];钱刚[1];周兴贵[1];段学志[1]

机构：[1]华东理工大学化工学院,化学工程联合国家重点实验室,上海200237

年份：2025

卷号：44

期号：3

起止页码：1347

中文期刊名：化工进展

外文期刊名：Chemical Industry and Engineering Progress

收录：;EI(收录号：20251718307545);北大核心:【北大核心2023】；

基金：上海市基础研究特区项目(22TQ1400100-15)。

语种：中文

中文关键词：甲醇;甲醛;催化剂;动力学;二氧化硅

外文关键词：methanol;formaldehyde;catalyst;kinetics;silica

摘要：采用蒸氨法,以二氧化硅(SiO_(2))为载体,制备了不同负载量的Cu/SiO_(2)催化剂,并考察了Cu催化剂粒径对甲醇非氧化脱氢制备甲醛性能的影响。表征结果显示,Cu的粒径随Cu负载量增加而增大。结合实验结果发现,当Cu粒径小于2.8nm时,甲醇脱氢生成甲醛的速率随Cu粒径增大而增大。据此,推测甲醇脱氢生成甲醛的活性位点可能存在于Cu催化剂表面的平板位点上。理论计算揭示在Cu(111)平板位上,甲醛生成途径主要涉及O—H键和C—H键的断裂,其中O-H键断裂是速率决定步骤。进一步,对具有较好甲醛产率的质量分数15%Cu/SiO_(2)催化剂进行动力学实验,得到甲醇转化的反应级数和活化能分别为0.42和32.42kJ/mol,甲醛生成的反应级数和活化能分别为0.45和30.23kJ/mol。上述研究发现为开发高活性和高选择性的甲醇无氧脱氢制甲醛催化剂提供了指导。
Utilizing the ammonia-evaporation method and employing silica(SiO_(2))as a support,we synthesized Cu/SiO_(2)catalysts with varying loadings.The influence of Cu catalyst particle size on the performance of methanol nonoxidative dehydrogenation for formaldehyde production was investigated.Characterization results revealed an increase in Cu particle size with Cu loading.The experimental results showed that the rate of methanol dehydrogenation increased with the increase in Cu particle size when the Cu particle size was less than 2.8nm.Accordingly,it was inferred that the active sites for methanol dehydrogenation to formaldehyde might reside on the planar surfaces of the Cu catalyst.Theoretical calculations unveiled that on the Cu(111)plane,the predominant pathways for formaldehyde generation involved the cleavage of O-H and C-H bonds,with the former as the rate-determining step.Furthermore,kinetic experiments were conducted on the 15%Cu/SiO_(2)catalyst,which exhibited superior formaldehyde yield.The obtained reaction order and activation energy for methanol conversion were 0.42 and 32.42kJ/mol,respectively,while those for formaldehyde production were 0.45 and 30.23kJ/mol,respectively.These findings could provide valuable insights for the development of highly active and selective catalysts for methanol nonoxidative dehydrogenation.