Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly process.However,hydrodechlorination catalyst...Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly process.However,hydrodechlorination catalysts for olefin production often suffer from poor stability.The Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination reaction.Brunauer-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of Pd.Comparative analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu content.Furthermore,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the reaction.As the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst activity.Moreover,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.展开更多
基金supported by the National Natural Science Foundation of China(22008212,22078292,21902124)Natural Science Basic Research Planning Shaanxi Province of China(2017ZDJC-29)+2 种基金Key Research and Development Project of Shaanxi Province(2018ZDXM-GY-173)China Postdoctoral Science Foundation(2019 M663848)Open cooperative innovation fund of Xi'an Institute of modern chemistry(SYJJ48).
文摘Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly process.However,hydrodechlorination catalysts for olefin production often suffer from poor stability.The Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination reaction.Brunauer-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of Pd.Comparative analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu content.Furthermore,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the reaction.As the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst activity.Moreover,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.
