乙烯气体深度脱氧催化剂性能研究OA北大核心CSTPCD

Precious metal deoxidation catalysts and chemisorbed deoxidation catalysts used for deoxidation from ethylene gas have drawbacks such as high cost,limited deoxidation capacity,and frequent regeneration requirements.Deep deoxidation catalysts for ethylene gas were prepared by loading Pd-Ag bimetallic active components onto the γ-Al2O3 support modified with rare earth oxides.The performance of the deep deoxidation catalysts for ethylene gas was investigated,and the structures of both the support and the catalyst were characterized using X-ray diffraction(XRD),N2 adsorption/desorption and thermogravimetric analysis.The results show that the rare earth-modified support has larger pore volume and pore size(average pore size increases from 1.90 nm before modification to 2.50 nm after modification),while the active component exhibits high dispersion and excellent low-temperature deoxidation activity.Oxygen in the ethylene gas can be reduced to less than 1×10-6(volume fraction of O2)at temperature between 110 ℃ and 180 ℃.The catalyst maintains high deoxidation activity during a 1650 h life test at conditions of space velocity of 5000 h-1 and reaction temperature of 145 ℃,without requiring reduction and regeneration before or during use.