新型ZrO_2膜管的研制及其对甲烷部分氧化的催化性能研究

Study of ZrO_2-CaO Membrane as Catalyst for Direct Oxidation of Methane to Methanol and Formaldehyde

利用ＳＯＬ－ＧＥＬ技术成功地制备了ＺｒＯ_２－ＣａＯ膜管，这种膜管由于能控制氧的扩散速度，并能活化它，因而容易和甲烷反应，表现了高的选择性生成甲醇、甲醛。实验发现最佳的制膜条件为：焙烧温度是７００～９００℃，膜厚４５～６０ｇＺｒ／ｃｍ￣２，ＣａＯ的最佳值为Ｘ＝０．０８～０．１５。实验也考察了最佳的反应条件，常压下反应温度为３５０℃，ＧＨＳＶ＝８０００～１００００ｈ￣（－１）。在这样的条件下获得了９５％的甲醇、甲醛选择性，大约１％转化率。

A new membrane tube-ZrO_2-CaO (CSZ) have been prepared by SOL--GELtechnology. It can control the diffusion velocity of oxgen.Oxgen diffusing through themembrane is activated and form active oxygen species which can easily react withmethane. So showing high selectivity to methanol and formaldehyde. the optimumpreparation condition is: Calcination temperature T = 700 -- 900 t, film thicknessb = 45 -- 60mgZr/cm', CaO additive amount x = 0.08 -- 0.15. The reaction condition have alsobeen investigated. At atmopheric pressure, the proper range of temperature is 350 oC orso, GHSV = 8000 -- 1000h--'. Under optimum reaction condiction we have got 95 %selectivity of methnaol and formaldehyde, about I % conversion of methane