Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the T...Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the TiO_(2)materials on the catalytic performance of Pd/TiO_(2)-101 and Pd/TiO_(2)-001 catalysts were investigated in the selective hydrogenation of acetylene to polymer-grade ethylene.The PdfTiO_(2)-101 catalyst exhibited enhanced performance in terms of acetylene conversion and ethylene yield.To understand these effects,the catalysts were characterized by H_(2)temperature-programmed desorption(H_(2)-TPD),H_(2)temperature-programmed reduction(H=-TPR),transmission electron microscopy(TEM),pulse CO chemisorption,X-ray photoelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The TEM and CO chemisorption results confirmed that Pd nanoparticles(NPs)on the TiO_(2)-101 support had a smaller average particle size(1.53 nm)and a higher dispersion(15.95%)than those on the TiO_(2)-001 support(average particle size of 4.36 nm and dispersion of 9.06%).The smaller particle size and higher dispersion of Pd on the Pd/TiO_(2)-101 catalyst provided more reaction active sites,which contributed to the improved catalytic activity of this supported catalyst.展开更多
Efficient conversion of straw cellulose to chemicals or fuels is an attracting topic today for the utiliza-tion of biomass to substitute for fossil resources.The development of catalysts is of vital importance.In this...Efficient conversion of straw cellulose to chemicals or fuels is an attracting topic today for the utiliza-tion of biomass to substitute for fossil resources.The development of catalysts is of vital importance.In this work,a composite catalyst metal-organic frameworks(MOFs)immobilized on three-dimensional reduced graphene oxide(3D-rGO)were synthesized by in situ growth of the MIL-101(Cr)within the 3D-rGO matrix.The supporting of 3D-rGO guaranteed the dispersion and acid site density of MIL-101(Cr).The MIL-101(Cr)@3D-rGO nanocomposite possesses excellent catalytic activity,stability,recyclability and is an idea catalyst for the efficient degradation of straw cellulose into formic acid(FA),acetic acid(AA)and oxalic acid(OA).A maximum FA conversion rates of 95.36%was obtained by using MIL-101(Cr)@3D-rGO(1:1)as catalyst and hydrothermal reaction at mild conditions of 200°C for 1h in alkaline aqueous medium.The MIL-101(Cr)@3D-rGO nanocomposite can be reused with high catalytic activity without any collapse of structure or leaching of chromium.展开更多
文摘中石化石油化工科学研究院有限公司开发的轻烃蒸汽重整制氢催化剂RSR-101/RSR-102在中国石化洛阳分公司4×10^(4)m^(3)/h制氢装置首次实现工业应用。工业标定结果表明,在反应压力为2.65 MPa、水碳摩尔比为3.33、转化炉入口温度为508.9℃、转化炉出口温度为772.5℃的条件下,轻烃折合成甲烷的转化率为79.7%,制氢装置单位产品的能耗较设计值降低了12.8%,每生产1 t H_(2)的CO_(2)排放量为8.01 t。制氢装置换装RSR-101/RSR-102催化剂组合后的各项运行参数均达到技术协议要求。
文摘Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the TiO_(2)materials on the catalytic performance of Pd/TiO_(2)-101 and Pd/TiO_(2)-001 catalysts were investigated in the selective hydrogenation of acetylene to polymer-grade ethylene.The PdfTiO_(2)-101 catalyst exhibited enhanced performance in terms of acetylene conversion and ethylene yield.To understand these effects,the catalysts were characterized by H_(2)temperature-programmed desorption(H_(2)-TPD),H_(2)temperature-programmed reduction(H=-TPR),transmission electron microscopy(TEM),pulse CO chemisorption,X-ray photoelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The TEM and CO chemisorption results confirmed that Pd nanoparticles(NPs)on the TiO_(2)-101 support had a smaller average particle size(1.53 nm)and a higher dispersion(15.95%)than those on the TiO_(2)-001 support(average particle size of 4.36 nm and dispersion of 9.06%).The smaller particle size and higher dispersion of Pd on the Pd/TiO_(2)-101 catalyst provided more reaction active sites,which contributed to the improved catalytic activity of this supported catalyst.
基金supported by the National Natural Science Foun-dation of China(Nos.U1906221 and 52070121)supported by grants from the Major Program of Shandong Province Technological Innovation Project(No.2020CXGC011403).
文摘Efficient conversion of straw cellulose to chemicals or fuels is an attracting topic today for the utiliza-tion of biomass to substitute for fossil resources.The development of catalysts is of vital importance.In this work,a composite catalyst metal-organic frameworks(MOFs)immobilized on three-dimensional reduced graphene oxide(3D-rGO)were synthesized by in situ growth of the MIL-101(Cr)within the 3D-rGO matrix.The supporting of 3D-rGO guaranteed the dispersion and acid site density of MIL-101(Cr).The MIL-101(Cr)@3D-rGO nanocomposite possesses excellent catalytic activity,stability,recyclability and is an idea catalyst for the efficient degradation of straw cellulose into formic acid(FA),acetic acid(AA)and oxalic acid(OA).A maximum FA conversion rates of 95.36%was obtained by using MIL-101(Cr)@3D-rGO(1:1)as catalyst and hydrothermal reaction at mild conditions of 200°C for 1h in alkaline aqueous medium.The MIL-101(Cr)@3D-rGO nanocomposite can be reused with high catalytic activity without any collapse of structure or leaching of chromium.
