The dehydrogenation of alkanes has emerged as a vital complementary process to address the increasing global demand for olefins.A key challenge remains in the construction of novel active centers that offer superior a...The dehydrogenation of alkanes has emerged as a vital complementary process to address the increasing global demand for olefins.A key challenge remains in the construction of novel active centers that offer superior activity,stability,and cost-effectiveness.Herein,tricoordinated cobalt atoms were successfully fabricated through an in-situ ligand-protected synthesis by introducing tungsten atoms into zeolite frameworks.These unsaturated Co species efficiently activate C-H bonds while suppressing C-C bond cleavage,resulting in exceptional catalytic activity and olefin selectivity in both propane and ethane dehydrogenation reactions.The optimized Co_(0.2%)@0.01W-S-1 catalyst demonstrated an impressive propylene formation rate of 15.2 molC_(3H6)gcC h^(-1)at 823 K and an ethylene formation rate of 240.3mol_(C2H4)g_(Co)^(-1)h^(-1)at 913 K,with propylene and ethylene selectivities of 99.0%and 97.5%,respectively.These results not only significantly surpass conventional tetracoordinated Co catalysts but also rival some Pt-based catalysts under similar conditions.Importantly,the catalyst exhibited excellent stability in dehydrogenation reactions,with no significant loss in catalytic activity after five consecutive regeneration cycles.This work offers valuable insights into the design of zeolite-supported non-precious metal catalysts with high activity and durability for efficient alkane dehydrogenation.展开更多
A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differentia...A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differential scanning calorimetry(TG-DSC),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and FTIR pyridine adsorption.The as-prepared heteropoly acids have a Keggin type structure.The synthesis of tetrahydrofuran by reactive distillation and cyclodehydration of 1,4-butanediol was studied using the tungsten-substituted molybdophosphoric acids as catalysts.The results of catalytic test indicated that the catalytic activity increased with the increase in the substitution number(n) of tungsten atom in H3PMo12-nWnO40·xH2O and was constant as the substitution number(n) was more than 8.The catalytic activity increased with the increase in the catalyst loading and the selectivity of tetrahydrofuran was nearly 100%.展开更多
基金supported by the National Key R&D Program of China(Grant No.2022YFA1506000)Gusu Innovation and Entrepreneurship Leading Talents Program(ZXL2022497)+5 种基金Jiangsu Distinguished Professor programfinancial support by National Natural Science Foundation of China(Grant No.22301057)Natural Science Foundation of Hebei Province(Grant No.B2023201065)Science Research Project of Hebei Education Department(Grant No.BJK2024103)supported by the Open Research Fund of Shanghai Key Laboratory of High-resolution Electron MicroscopyOpen Project of State Key Laboratory of Supramolecular Structure and Materials(sklssm2024019),ShanghaiTech University。
文摘The dehydrogenation of alkanes has emerged as a vital complementary process to address the increasing global demand for olefins.A key challenge remains in the construction of novel active centers that offer superior activity,stability,and cost-effectiveness.Herein,tricoordinated cobalt atoms were successfully fabricated through an in-situ ligand-protected synthesis by introducing tungsten atoms into zeolite frameworks.These unsaturated Co species efficiently activate C-H bonds while suppressing C-C bond cleavage,resulting in exceptional catalytic activity and olefin selectivity in both propane and ethane dehydrogenation reactions.The optimized Co_(0.2%)@0.01W-S-1 catalyst demonstrated an impressive propylene formation rate of 15.2 molC_(3H6)gcC h^(-1)at 823 K and an ethylene formation rate of 240.3mol_(C2H4)g_(Co)^(-1)h^(-1)at 913 K,with propylene and ethylene selectivities of 99.0%and 97.5%,respectively.These results not only significantly surpass conventional tetracoordinated Co catalysts but also rival some Pt-based catalysts under similar conditions.Importantly,the catalyst exhibited excellent stability in dehydrogenation reactions,with no significant loss in catalytic activity after five consecutive regeneration cycles.This work offers valuable insights into the design of zeolite-supported non-precious metal catalysts with high activity and durability for efficient alkane dehydrogenation.
基金Supported by Research Funds from Chinese Education Department (2003406)Bureau of Science and Technology of Jiangsu Province (BG2006025)
文摘A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differential scanning calorimetry(TG-DSC),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and FTIR pyridine adsorption.The as-prepared heteropoly acids have a Keggin type structure.The synthesis of tetrahydrofuran by reactive distillation and cyclodehydration of 1,4-butanediol was studied using the tungsten-substituted molybdophosphoric acids as catalysts.The results of catalytic test indicated that the catalytic activity increased with the increase in the substitution number(n) of tungsten atom in H3PMo12-nWnO40·xH2O and was constant as the substitution number(n) was more than 8.The catalytic activity increased with the increase in the catalyst loading and the selectivity of tetrahydrofuran was nearly 100%.
