Abstract The catalyst CoO-MoO₃/MgO-Al₂O₃ for water gas shift reaction was prepared by means of mixed calcinations. The sulfurized catalyst prepared and contrast ones (MoO₃/Al₂O₃, CoO/Al₂O₃ and MoO₃/MgO-Al₂O₃) were characterized by using XPS technique. The results show that the state of Mo species on the catalyst samples coexist as Mo⁶⁺, Mo⁵⁺ and Mo⁴⁺. The content of the Mo⁶⁺ species decrease after the addition of the promoter MgO or CoO to the catalyst and the contrast ones, but the concentration of Mo⁵⁺ and [S-S]^2- increase, and the catalytic activity at low temperature was found to be improved (99% of Co conversion at 200°C being found).The pathway of the catalytic reaction may follow the mechanism Mo⁴⁺～Mo⁵⁺.
Key words Co-Mo/MgO-Al₂O₃ catalyst, MgAl₂O₄ spinel, Water gas shift, XPS

Co-Mo/MgO-Al₂O₃水煤气变换催化剂的XPS表征

郑泉兴 陈颖 王琪 李一农 林仁存 方维平 杨意泉^*
(厦门大学化学化工学院物理化学研究所 固体表面物理化学国家重点实验室 厦门 361005)

摘要 以混合煅烧法制备了水煤气变换催化剂CoO-MoO₃/MgO-Al₂O₃，对硫化态催化剂及参比样(MoO₃/Al₂O₃，CoO/Al₂O₃和MoO₃/MgO-Al₂O₃)进行XPS表征。结果显示，钼物种含Mo⁶⁺、Mo⁵⁺和Mo⁴⁺混合价态；添加MgO或CoO助剂后，Mo⁶⁺物种含量减少，Mo⁵⁺和[S-S]^2-物种浓度增加，催化剂低温活性得到提高(在200°C时CO转化率达99%)。其催化反应过程可能按Mo⁴⁺～Mo⁵⁺氧化还原机理进行。
关键词 Co-Mo/MgO-Al₂O₃催化剂 镁铝尖晶石 水煤气变换 XPS

郑泉兴 男，24岁，硕士生，现从事多相催化研究。*联系人 E-mail:yyiquan@163.com
福省百千万人才工程(K39002)，厦门市2003科技创新基金资助项目(350z20031082)

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