{"title":"Synergy of metal–support interaction and positive Pd species promoting efficient C–Cl bond activation on Pd-based Ce-MOF-derived catalysts","authors":"Xiao-Jie Hu, Yu-Han Sun, Ling-Yue Liu, Dan-Jun Mao, Shou-Rong Zheng","doi":"10.1007/s12598-024-02826-2","DOIUrl":null,"url":null,"abstract":"<p>Monochloroacetic acid (MCAA) is identified as a highly carcinogenic disinfection by-product in chlorinated drinking water. In this study, a series of CeO<sub>2</sub>-supported Pd catalysts (Pd/MCeO<sub>2</sub>) were synthesized through one-step calcination of Pd-loaded Ce-UiO-66-BDC (Ce-MOF), and the liquid-phase catalytic hydrodechlorination of MCAA was explored using these catalysts. For comparison, Pd/CeO<sub>2</sub> catalysts were additionally synthesized using the conventional impregnation method. The characterization results reveal that the catalysts exhibit strong metal–support interaction, leading to high Pd dispersion and Pd<sup><i>n</i>+</sup> content. Additionally, the calcination temperature significantly influences catalytic performance, with the catalyst calcined at 500 °C (Pd/MCeO<sub>2</sub>-500) demonstrating the highest catalytic activity and achieving complete dechlorination of MCAA within 50 min. Furthermore, it is found that the catalytic MCAA hydrodechlorination using the catalysts adheres to the Langmuir–Hinshelwood model. Accordingly, low reaction pH is favorable for the catalytic hydrodechlorination of MCAA, enhancing MCAA adsorption on the catalyst surface due to the electrostatic interaction between MCAA and the catalyst surface. Theoretical results suggest that the presence of Pd<sup><i>n</i>+</sup> efficiently facilitates MCAA adsorption and C–Cl cleavage, thus significantly enhancing the liquid-phase catalytic hydrodechlorination.</p><h3 data-test=\"abstract-sub-heading\">Graphical abstract</h3>\n","PeriodicalId":749,"journal":{"name":"Rare Metals","volume":null,"pages":null},"PeriodicalIF":9.6000,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Rare Metals","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1007/s12598-024-02826-2","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Monochloroacetic acid (MCAA) is identified as a highly carcinogenic disinfection by-product in chlorinated drinking water. In this study, a series of CeO2-supported Pd catalysts (Pd/MCeO2) were synthesized through one-step calcination of Pd-loaded Ce-UiO-66-BDC (Ce-MOF), and the liquid-phase catalytic hydrodechlorination of MCAA was explored using these catalysts. For comparison, Pd/CeO2 catalysts were additionally synthesized using the conventional impregnation method. The characterization results reveal that the catalysts exhibit strong metal–support interaction, leading to high Pd dispersion and Pdn+ content. Additionally, the calcination temperature significantly influences catalytic performance, with the catalyst calcined at 500 °C (Pd/MCeO2-500) demonstrating the highest catalytic activity and achieving complete dechlorination of MCAA within 50 min. Furthermore, it is found that the catalytic MCAA hydrodechlorination using the catalysts adheres to the Langmuir–Hinshelwood model. Accordingly, low reaction pH is favorable for the catalytic hydrodechlorination of MCAA, enhancing MCAA adsorption on the catalyst surface due to the electrostatic interaction between MCAA and the catalyst surface. Theoretical results suggest that the presence of Pdn+ efficiently facilitates MCAA adsorption and C–Cl cleavage, thus significantly enhancing the liquid-phase catalytic hydrodechlorination.
期刊介绍:
Rare Metals is a monthly peer-reviewed journal published by the Nonferrous Metals Society of China. It serves as a platform for engineers and scientists to communicate and disseminate original research articles in the field of rare metals. The journal focuses on a wide range of topics including metallurgy, processing, and determination of rare metals. Additionally, it showcases the application of rare metals in advanced materials such as superconductors, semiconductors, composites, and ceramics.