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本文运用原位红外光谱研究了在γ—Al_2O_3上CO、CO_2的吸附及其与H_2或H_2O的共吸附。观测到不同情况下HCOO~-的生成规律及其随温度变化的行为。在(CO+H_2)的共吸附中观察到HCO_3~-向HCOO~-表面体的转变。在(CO+H_2O)共吸附中,HCOO~-不经HCO_3~-的中间步骤而直接生成。在CO_2的吸附中,检测到两种热稳定性不同的表面HCO_3~-体。而(CO_2+H_2)共吸附中也观察到了HCOO~-的形成。研究了表面甲酸体在真空中热分解以及它同H_2或H_2O的反应,证实了表面甲酸体更易于同H_2O反应。这三种情况下甲酸体显著反应温度分别约为400℃、300℃、100℃。
In situ FTIR spectroscopy was used to study the adsorption of CO and CO_2 on γ-Al_2O_3 and its co-adsorption with H_2 or H_2O. The formation of HCOO ~ - under different conditions and its behavior with temperature were observed. In the co-adsorption of (CO + H 2) HCO 3 ~ - to HCOO ~ -surface transitions were observed. In (CO + H_2O) co-adsorption, HCOO ~ - was generated directly without an intermediate step of HCO_3 ~. In the CO 2 adsorption, two kinds of surface HCO 3 ~ - with different thermal stability were detected. However, the formation of HCOO ~ - was also observed in the co-adsorption of (CO 2 + H 2). The thermal decomposition of surface formic acid in vacuum and its reaction with H 2 or H 2 O were investigated. It was confirmed that the surface formic acid was more easily reacted with H 2 O. In all three cases, the significant reaction temperatures of formate were about 400 ℃, 300 ℃ and 100 ℃, respectively.