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采用XRD、BET、NH3 TPD、TPR等方法对CeO2 以及La2 O3和CeO2 共同改性的γ -Al2 O3担载Pd催化剂的结构和性能进行研究。结果表明 ,CeO2 改性的Pd/γ -Al2 O3具有很高的甲醇低温分解活性 ,但表面酸性导致生成较多的二甲醚 ;La2 O3的加入掩蔽了催化剂的表面酸性 ,同时促进了CeO2 在γ -Al2 O3载体内外表面的分散 ,使活性组分Pd和CeO2 之间的相互作用加强 ,从而大大提高了甲醇的裂解率。
The structure and properties of γ -Al 2 O 3 supported Pd catalysts modified by CeO 2, La 2 O 3 and CeO 2 were studied by XRD, BET, NH 3 TPD and TPR methods. The results showed that the CeO2 modified Pd / γ -Al2 O3 had a high methanol decomposition activity but the surface acidity led to the formation of more DME. The addition of La2O3 obscured the surface acidity of the catalyst and promoted the oxidation of CeO2 The dispersion of γ-Al 2 O 3 support inner and outer surfaces strengthens the interaction between Pd and CeO 2, which greatly improves the cracking rate of methanol.