{"title":"Catalytic combustion of propane over second metal-modified Ru supported on CeO2 nanosheet","authors":"","doi":"10.1016/j.seppur.2024.129874","DOIUrl":null,"url":null,"abstract":"<div><div>Among the CeO<sub>2</sub> supported noble metal catalysts, Ru/CeO<sub>2</sub> shows the highest activity for propane combustion. However, Ru/CeO<sub>2</sub> catalysts still exhibit some problems such as poor thermal stability and high temperature volatilization loss of Ru species. In this work, based on electronic structure modification and acid-base-redox property regulation, the active Ru component in Ru/CeO<sub>2</sub> was modified with a second element to prepare for propane (C<sub>3</sub>H<sub>8</sub>) combustion. Activity test and characterizations illustrated that all the selected elements reduce the C<sub>3</sub>H<sub>8</sub> combustion activity due to a corresponding reduction in active Ru-O-Ce species. With the addition of Cs with strong electron-donating leads to the stabilization of Ce<sup>3+</sup> within the CeO<sub>2</sub>, consequently diminishing its redox capabilities thus exhibits suboptimal activity and stability. However, the moderately electron-donating alkaline earth metal Ba stabilizes the low-cost Ru species and improves the thermal stability. In contrast, the strongly electron-withdrawing element Nb reduces the stability of low-valence Ru species and leads to the easy loss of Ru at high temperatures. However, the prepared NbRu/CeO<sub>2</sub> catalyst shows better resistance to chlorine poisoning and CO<sub>2</sub> due to the enhancement of acidity. Finally, the reaction pathway for propane oxidation was thoroughly investigated by <em>in-situ</em> DRIFTS over the modified Ru/CeO<sub>2</sub> catalysts. The addition of Cs improves Ru′ dispersion, which in turn facilitates the oxidation of propane to propanol. With the addition of Ba, the conversion of carboxylic acid species to acid ester species is accelerated. While the addition of Nb lead to a decrease in the variety of adsorbates.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":null,"pages":null},"PeriodicalIF":8.1000,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Separation and Purification Technology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S138358662403613X","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Among the CeO2 supported noble metal catalysts, Ru/CeO2 shows the highest activity for propane combustion. However, Ru/CeO2 catalysts still exhibit some problems such as poor thermal stability and high temperature volatilization loss of Ru species. In this work, based on electronic structure modification and acid-base-redox property regulation, the active Ru component in Ru/CeO2 was modified with a second element to prepare for propane (C3H8) combustion. Activity test and characterizations illustrated that all the selected elements reduce the C3H8 combustion activity due to a corresponding reduction in active Ru-O-Ce species. With the addition of Cs with strong electron-donating leads to the stabilization of Ce3+ within the CeO2, consequently diminishing its redox capabilities thus exhibits suboptimal activity and stability. However, the moderately electron-donating alkaline earth metal Ba stabilizes the low-cost Ru species and improves the thermal stability. In contrast, the strongly electron-withdrawing element Nb reduces the stability of low-valence Ru species and leads to the easy loss of Ru at high temperatures. However, the prepared NbRu/CeO2 catalyst shows better resistance to chlorine poisoning and CO2 due to the enhancement of acidity. Finally, the reaction pathway for propane oxidation was thoroughly investigated by in-situ DRIFTS over the modified Ru/CeO2 catalysts. The addition of Cs improves Ru′ dispersion, which in turn facilitates the oxidation of propane to propanol. With the addition of Ba, the conversion of carboxylic acid species to acid ester species is accelerated. While the addition of Nb lead to a decrease in the variety of adsorbates.
期刊介绍:
Separation and Purification Technology is a premier journal committed to sharing innovative methods for separation and purification in chemical and environmental engineering, encompassing both homogeneous solutions and heterogeneous mixtures. Our scope includes the separation and/or purification of liquids, vapors, and gases, as well as carbon capture and separation techniques. However, it's important to note that methods solely intended for analytical purposes are not within the scope of the journal. Additionally, disciplines such as soil science, polymer science, and metallurgy fall outside the purview of Separation and Purification Technology. Join us in advancing the field of separation and purification methods for sustainable solutions in chemical and environmental engineering.