{"title":"Dual active sites over Cu-ZnO-ZrO2 catalysts for carbon dioxide hydrogenation to methanol","authors":"Xiucheng Sun, Yifei Jin, Zaizhe Cheng, Guojun Lan, Xiaolong Wang, Yiyang Qiu, Yanjiang Wang, Huazhang Liu, Ying Li","doi":"10.1016/j.jes.2022.10.002","DOIUrl":null,"url":null,"abstract":"<div><p>CO<sub>2</sub><span> hydrogenation to methanol is a significant approach to tackle the problem of global warming and simultaneously meet the demand for the portable fuel. Cu-ZnO catalysts with various kinds of promoters have received wide attention. However, the role of promoter and the form of active sites in CO</span><sub>2</sub> hydrogenation are still in debate. Here, various molar ratios of ZrO<sub>2</sub> were added into the Cu-ZnO catalysts to tune the distributions of Cu<sup>0</sup> and Cu<sup>+</sup> species. A volcano-like trend between the ratio of Cu<sup>+</sup>/ (Cu<sup>+</sup> + Cu<sup>0</sup>) and the amount of ZrO<sub>2</sub> is presented, among which the CuZn10Zr (the molar ratio of ZrO<sub>2</sub> is 10%) catalyst reaches the highest value. Correspondingly, the maximum value of space-time yield to methanol with 0.65 g<sub>MeOH</sub>/(g<sub>cat</sub>·hr) is obtained on CuZn10Zr at reaction conditions of 220°C and 3 MPa. Detailed characterizations demonstrate that dual active sites are proposed during CO<sub>2</sub> hydrogenation over CuZn10Zr catalyst. The exposed Cu<sup>0</sup> takes participate in the activation of H<sub>2</sub>, while on the Cu<sup>+</sup> species, the intermediate of formate from the co-adsorption of CO<sub>2</sub> and H<sub>2</sub> prefers to be further hydrogenated to CH<sub>3</sub><span>OH than decomposing into the by-product of CO, yielding a high selectivity of methanol.</span></p></div>","PeriodicalId":15774,"journal":{"name":"Journal of environmental sciences","volume":"131 ","pages":"Pages 162-172"},"PeriodicalIF":6.9000,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"5","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of environmental sciences","FirstCategoryId":"1089","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1001074222004910","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Environmental Science","Score":null,"Total":0}
引用次数: 5
Abstract
CO2 hydrogenation to methanol is a significant approach to tackle the problem of global warming and simultaneously meet the demand for the portable fuel. Cu-ZnO catalysts with various kinds of promoters have received wide attention. However, the role of promoter and the form of active sites in CO2 hydrogenation are still in debate. Here, various molar ratios of ZrO2 were added into the Cu-ZnO catalysts to tune the distributions of Cu0 and Cu+ species. A volcano-like trend between the ratio of Cu+/ (Cu+ + Cu0) and the amount of ZrO2 is presented, among which the CuZn10Zr (the molar ratio of ZrO2 is 10%) catalyst reaches the highest value. Correspondingly, the maximum value of space-time yield to methanol with 0.65 gMeOH/(gcat·hr) is obtained on CuZn10Zr at reaction conditions of 220°C and 3 MPa. Detailed characterizations demonstrate that dual active sites are proposed during CO2 hydrogenation over CuZn10Zr catalyst. The exposed Cu0 takes participate in the activation of H2, while on the Cu+ species, the intermediate of formate from the co-adsorption of CO2 and H2 prefers to be further hydrogenated to CH3OH than decomposing into the by-product of CO, yielding a high selectivity of methanol.
期刊介绍:
Journal of Environmental Sciences is an international peer-reviewed journal established in 1989. It is sponsored by the Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, and it is jointly published by Elsevier and Science Press. It aims to foster interdisciplinary communication and promote understanding of significant environmental issues. The journal seeks to publish significant and novel research on the fate and behaviour of emerging contaminants, human impact on the environment, human exposure to environmental contaminants and their health effects, and environmental remediation and management. Original research articles, critical reviews, highlights, and perspectives of high quality are published both in print and online.