用微型催化反应装置结合X射线衍射(XRD)、H2化学吸附、NH3吸附-程序升温脱附(NH3-TPD)和H2-程序升温还原等多种物理化学手段研究了丙烷脱氢负载型Pt Sn Na/SUZ-4催化剂中Na+助剂组分的作用。结果表明,Na+组分可中和SUZ-4载体表面的强酸...用微型催化反应装置结合X射线衍射(XRD)、H2化学吸附、NH3吸附-程序升温脱附(NH3-TPD)和H2-程序升温还原等多种物理化学手段研究了丙烷脱氢负载型Pt Sn Na/SUZ-4催化剂中Na+助剂组分的作用。结果表明,Na+组分可中和SUZ-4载体表面的强酸中心、提高催化剂的Pt金属分散度、抑制脱氢产物的裂解和积炭的生成,从而提高催化剂的丙烷脱氢选择性和反应稳定性。但是过量Na+组分的存在会削弱Sn物种与载体之间的相互作用,使其易被还原,导致催化剂丙烷脱氢活性显著下降。展开更多
A series of PtSn/hierarchical ZSM-5 catalysts were developed for propane dehydrogenation,in which the PtSn bimetallic particles are confined in the mesopores of hierarchical ZSM-5 zeolite.The synthesis of PtSn/hierarc...A series of PtSn/hierarchical ZSM-5 catalysts were developed for propane dehydrogenation,in which the PtSn bimetallic particles are confined in the mesopores of hierarchical ZSM-5 zeolite.The synthesis of PtSn/hierarchical ZSM-5 catalysts was achieved via the loading of Pt and Sn species onto the hierarchical ZSM-5 catalysts that are obtained through a desilication of conventional ZSM-5.The PtSn/hierarchical ZSM-5 catalysts were fully characterized by XRD,N_(2) adsorption,STEM,XPS,and CO-IR techniques,which reveals that highly dispersed PtSn bimetallic nanoparticles are enclosed into mesopores of hierarchical ZSM-5.The catalytic performance of PtSn/hierarchical ZSM-5 is greatly affected by the concentrations of alkali solution in the desilication process and Sn/Pt ratios in PtSn bimetallic particles.The PtSn1.00/ZSM-5(0.8)catalyst shows the highest efficiency in propane dehydrogenation,which gives an initial conversion of 46%and selectivity of 98%at 570℃.The high efficiency in these PtSn/hierarchical ZSM-5 catalysts for propane dehydrogenation is mainly ascribed to the confinement of PtSn particles in the mesopores of hierarchical ZSM-5 zeolite.展开更多
文摘用微型催化反应装置结合X射线衍射(XRD)、H2化学吸附、NH3吸附-程序升温脱附(NH3-TPD)和H2-程序升温还原等多种物理化学手段研究了丙烷脱氢负载型Pt Sn Na/SUZ-4催化剂中Na+助剂组分的作用。结果表明,Na+组分可中和SUZ-4载体表面的强酸中心、提高催化剂的Pt金属分散度、抑制脱氢产物的裂解和积炭的生成,从而提高催化剂的丙烷脱氢选择性和反应稳定性。但是过量Na+组分的存在会削弱Sn物种与载体之间的相互作用,使其易被还原,导致催化剂丙烷脱氢活性显著下降。
基金supports of the National Natural Science Foundation of China(21878050,22178062)Foundation of State Key Labora-tory of Coal Conversion(J21-22-620)Green Petrochemical Engineering Base of Intelligence Introduction for Innovation(111 Project D17005)are gratefully acknowledged.
文摘A series of PtSn/hierarchical ZSM-5 catalysts were developed for propane dehydrogenation,in which the PtSn bimetallic particles are confined in the mesopores of hierarchical ZSM-5 zeolite.The synthesis of PtSn/hierarchical ZSM-5 catalysts was achieved via the loading of Pt and Sn species onto the hierarchical ZSM-5 catalysts that are obtained through a desilication of conventional ZSM-5.The PtSn/hierarchical ZSM-5 catalysts were fully characterized by XRD,N_(2) adsorption,STEM,XPS,and CO-IR techniques,which reveals that highly dispersed PtSn bimetallic nanoparticles are enclosed into mesopores of hierarchical ZSM-5.The catalytic performance of PtSn/hierarchical ZSM-5 is greatly affected by the concentrations of alkali solution in the desilication process and Sn/Pt ratios in PtSn bimetallic particles.The PtSn1.00/ZSM-5(0.8)catalyst shows the highest efficiency in propane dehydrogenation,which gives an initial conversion of 46%and selectivity of 98%at 570℃.The high efficiency in these PtSn/hierarchical ZSM-5 catalysts for propane dehydrogenation is mainly ascribed to the confinement of PtSn particles in the mesopores of hierarchical ZSM-5 zeolite.
