Jianhao Jiao , Yucai Qin , Jian Zheng , Yu Hui , Li Zhang , Xionghou Gao , Lijuan Song
{"title":"Synergistic mechanism between Brønsted acid site and active cerium species in hydride transfer reaction over CeY zeolites","authors":"Jianhao Jiao , Yucai Qin , Jian Zheng , Yu Hui , Li Zhang , Xionghou Gao , Lijuan Song","doi":"10.1016/j.jre.2020.06.001","DOIUrl":null,"url":null,"abstract":"<div><p><span><span>In this study, cyclohexene was used as a representative of </span>olefin<span> and catalyzed by CeY zeolites<span> in a fixed-bed reactor under mild conditions, and the influence of Ce species in hydride transfer reaction over CeY zeolites was evaluated. CeY zeolites show more excellent hydride transfer properties than HY zeolite. Based on the results of almost identical Brønsted acid properties but not the product distributions for 0.075CeY and 0.075CeY(DC) samples, it should be suggested that the Brønsted acid strength and density are not the deciding factors to the hydride transfer reaction. A unique band at 1442 cm</span></span></span><sup>−1</sup> <em>in situ</em><span> FTIR spectroscopy spectra are assigned to pyridine complexes bonded to a class of active Ce species that could reversibly migrate from the core of SOD cages to its 6-rings mouth towards the supercages. These results provide valuable information that these active Ce species should play a synergistic role with the Brønsted acid sites in enhancing the hydride transfer reaction with a bimolecular mechanism over CeY zeolites.</span></p></div>","PeriodicalId":16940,"journal":{"name":"Journal of Rare Earths","volume":"38 8","pages":"Pages 912-920"},"PeriodicalIF":7.2000,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jre.2020.06.001","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Rare Earths","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1002072120302829","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
引用次数: 2
Abstract
In this study, cyclohexene was used as a representative of olefin and catalyzed by CeY zeolites in a fixed-bed reactor under mild conditions, and the influence of Ce species in hydride transfer reaction over CeY zeolites was evaluated. CeY zeolites show more excellent hydride transfer properties than HY zeolite. Based on the results of almost identical Brønsted acid properties but not the product distributions for 0.075CeY and 0.075CeY(DC) samples, it should be suggested that the Brønsted acid strength and density are not the deciding factors to the hydride transfer reaction. A unique band at 1442 cm−1in situ FTIR spectroscopy spectra are assigned to pyridine complexes bonded to a class of active Ce species that could reversibly migrate from the core of SOD cages to its 6-rings mouth towards the supercages. These results provide valuable information that these active Ce species should play a synergistic role with the Brønsted acid sites in enhancing the hydride transfer reaction with a bimolecular mechanism over CeY zeolites.
期刊介绍:
The Journal of Rare Earths reports studies on the 17 rare earth elements. It is a unique English-language learned journal that publishes works on various aspects of basic theory and applied science in the field of rare earths (RE). The journal accepts original high-quality original research papers and review articles with inventive content, and complete experimental data. It represents high academic standards and new progress in the RE field. Due to the advantage of abundant RE resources of China, the research on RE develops very actively, and papers on the latest progress in this field emerge every year. It is not only an important resource in which technicians publish and obtain their latest research results on RE, but also an important way of reflecting the updated progress in RE research field.
The Journal of Rare Earths covers all research and application of RE rare earths including spectroscopy, luminescence and phosphors, rare earth catalysis, magnetism and magnetic materials, advanced rare earth materials, RE chemistry & hydrometallurgy, RE metallography & pyrometallurgy, RE new materials, RE solid state physics & solid state chemistry, rare earth applications, RE analysis & test, RE geology & ore dressing, etc.