Marc Arnau, Isabel Teixidó, Jordi Sans, Pau Turon and Carlos Alemán
{"title":"Thermoelectrically polarized amorphous silica promotes sustainable carbon dioxide conversion into valuable chemical products†","authors":"Marc Arnau, Isabel Teixidó, Jordi Sans, Pau Turon and Carlos Alemán","doi":"10.1039/D4SE01389A","DOIUrl":null,"url":null,"abstract":"<p >Electrically polarized amorphous silica (aSiO<small><sub>2</sub></small>) is demonstrated to be an efficient and viable metal-free heterogeneous catalyst for the conversion of CO<small><sub>2</sub></small> into valuable chemical products. The catalyst was prepared applying a thermoelectric polarization process in air to commercially available aSiO<small><sub>2</sub></small> nanoparticles. Four polarization temperatures were assayed (150, 500, 800 and 1000 °C), the larger structural and chemical changes induced by the polarization treatment being observed at 150 and 500 °C. The polarization at such temperatures reduced considerably the electrical resistance of calcined aSiO<small><sub>2</sub></small>, while no significant change was detected at 800 and 1000 °C. Polarized aSiO<small><sub>2</sub></small> was tested as heterogeneous catalysts for the reaction of CO<small><sub>2</sub></small> with water at mild reaction conditions (120 °C, 6 bar of CO<small><sub>2</sub></small>, 40 mL of water, 72 h). The highest catalytic activity was observed with aSiO<small><sub>2</sub></small> polarized at 150 °C, which was attributed to the structural defects induced during the thermoelectric polarization treatment. Thus, CO<small><sub>2</sub></small> was converted into a mixture of formic acid (39.9%), acetic acid (44.4%) and dioxane (15.7%). Although the catalytic process was not selective, the yields were not only very high but also allowed obtaining a significant amount of dioxane, a product with four carbon atoms, which is very unusual in processes catalyzed by polarized ceramics. In summary, polarized aSiO<small><sub>2</sub></small> can be used as a sustainable and low-cost raw material to prepare metal-free catalysts by means of a thermoelectric polarization process at 150 °C. This catalyst is capable of capturing CO<small><sub>2</sub></small> to produce valuable chemical products by applying mild reaction conditions.</p>","PeriodicalId":104,"journal":{"name":"Sustainable Energy & Fuels","volume":" 24","pages":" 5937-5949"},"PeriodicalIF":5.0000,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/se/d4se01389a?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sustainable Energy & Fuels","FirstCategoryId":"88","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2024/se/d4se01389a","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Electrically polarized amorphous silica (aSiO2) is demonstrated to be an efficient and viable metal-free heterogeneous catalyst for the conversion of CO2 into valuable chemical products. The catalyst was prepared applying a thermoelectric polarization process in air to commercially available aSiO2 nanoparticles. Four polarization temperatures were assayed (150, 500, 800 and 1000 °C), the larger structural and chemical changes induced by the polarization treatment being observed at 150 and 500 °C. The polarization at such temperatures reduced considerably the electrical resistance of calcined aSiO2, while no significant change was detected at 800 and 1000 °C. Polarized aSiO2 was tested as heterogeneous catalysts for the reaction of CO2 with water at mild reaction conditions (120 °C, 6 bar of CO2, 40 mL of water, 72 h). The highest catalytic activity was observed with aSiO2 polarized at 150 °C, which was attributed to the structural defects induced during the thermoelectric polarization treatment. Thus, CO2 was converted into a mixture of formic acid (39.9%), acetic acid (44.4%) and dioxane (15.7%). Although the catalytic process was not selective, the yields were not only very high but also allowed obtaining a significant amount of dioxane, a product with four carbon atoms, which is very unusual in processes catalyzed by polarized ceramics. In summary, polarized aSiO2 can be used as a sustainable and low-cost raw material to prepare metal-free catalysts by means of a thermoelectric polarization process at 150 °C. This catalyst is capable of capturing CO2 to produce valuable chemical products by applying mild reaction conditions.
期刊介绍:
Sustainable Energy & Fuels will publish research that contributes to the development of sustainable energy technologies with a particular emphasis on new and next-generation technologies.