Ti Ce complex oxide catalysts for catalytic wet air oxidation of acetic acid as model reactant were prepared by coprecipitation and impregnation methods. The catalysts are very stable during the reaction. The presence...Ti Ce complex oxide catalysts for catalytic wet air oxidation of acetic acid as model reactant were prepared by coprecipitation and impregnation methods. The catalysts are very stable during the reaction. The presence of Bi as base center has promotion effect on the catalyst activity. The optimal Bi content is about 4% (molar fraction). With the increase of calcination temperature, the BET surface area of the catalysts is decreased and so is the activity of the catalysts. The activity of the catalysts and the Bi effect are discussed based on the reference results.展开更多
采用表面反应改性法制备了ZrO2 SiO2(ZrSiO)表面复合物,用等体积浸渍法制备了ZrSiO负载的Ni Cu双金属催化剂,并用IR、TPD、TPSR和微反技术考察了CH4、H2O和O2在催化剂表面上的化学吸附及反应性能。结果表明,在Ni Cu ZrSiO催化剂上存在着...采用表面反应改性法制备了ZrO2 SiO2(ZrSiO)表面复合物,用等体积浸渍法制备了ZrSiO负载的Ni Cu双金属催化剂,并用IR、TPD、TPSR和微反技术考察了CH4、H2O和O2在催化剂表面上的化学吸附及反应性能。结果表明,在Ni Cu ZrSiO催化剂上存在着Ni Cu金属位,Lewis酸位Znn+和碱位Zr O-三类活性中心;CH4和H2O在金属位和Lewis酸位Znn+和碱位Zr O-的协同作用下可形成解离吸附态;CH4、H2O和O2在Ni Cu ZrSiO催化剂表面上的主要反应产物为H2和CO2,选择性均在95%以上。展开更多
文摘Ti Ce complex oxide catalysts for catalytic wet air oxidation of acetic acid as model reactant were prepared by coprecipitation and impregnation methods. The catalysts are very stable during the reaction. The presence of Bi as base center has promotion effect on the catalyst activity. The optimal Bi content is about 4% (molar fraction). With the increase of calcination temperature, the BET surface area of the catalysts is decreased and so is the activity of the catalysts. The activity of the catalysts and the Bi effect are discussed based on the reference results.
文摘采用表面反应改性法制备了ZrO2 SiO2(ZrSiO)表面复合物,用等体积浸渍法制备了ZrSiO负载的Ni Cu双金属催化剂,并用IR、TPD、TPSR和微反技术考察了CH4、H2O和O2在催化剂表面上的化学吸附及反应性能。结果表明,在Ni Cu ZrSiO催化剂上存在着Ni Cu金属位,Lewis酸位Znn+和碱位Zr O-三类活性中心;CH4和H2O在金属位和Lewis酸位Znn+和碱位Zr O-的协同作用下可形成解离吸附态;CH4、H2O和O2在Ni Cu ZrSiO催化剂表面上的主要反应产物为H2和CO2,选择性均在95%以上。
文摘制备了 V2 O5 -Si O2 、Mo O3-Si O2 和 Mo O3-V2 O5 -Si O2 3种复合氧化物催化剂。用程序升温还原 (TPR)研究了各复合氧化物的表面构造及其催化活性 ,用化学吸附红外光谱 (IR)研究了各复合氧化物样品对异丁烷和异丁烯的化学吸附性能。实验结果表明 ,上述复合氧化物催化剂中 ,Si和 V或 Mo通过氧桥键合 ,使得 V O 、Mo O的氧化能力有所减弱 ,从而更加适合于选择氧化的要求。异丁烷在 Mo的复合氧化物中为桥式吸附 ,有利于脱氢。但在 V O诸点上 ,异丁烷为线式吸附 ,容易发生深度氧化。异丁烯在复合氧化物中的 V O、 Mo O均为线式吸附 ,V吸附的能力较强。复合氧化物中的 V O、 Mo O 是异丁烯脱氢。
