碳气化反应的催化机理研究

Study on Catalytic Mechanism of Boudouard Reaction

通过失重法和X-ray衍射分析手段,研究了碱金属盐复合氧化物和卤盐对碳气化反应的影响规律。对于相同的阴离子,钾盐的催化性能好于钠盐,钠盐的催化效果又优于锂盐;对于同一种阳离子的复合氧化物的催化活性规律为:硝酸盐>氢氧化物>碳酸盐>硫酸盐>偏硅酸盐>磷酸盐,对于同一种阳离子的卤盐的催化活性规律为:氟盐>氯盐>碘盐>溴盐。提出了一种新的微观催化机理:碱金属盐的催化作用在于催化剂能改变C-C化学键的作用程度,从而加速反应的进行。催化活性与阳离子、阴离子种类以及化合物的稳定性有关,这3方面因素相互耦合,共同决定添加剂的催化性能。

Influence of salts of alkaline metals, composite oxides and holoids on boudouard reaction was studied by XRD analysis and thermogravimetry experiment. For salts of alkaline metals with same anion, the power sequence of the catalytic effect is K^＋〉Na^＋〉Li^＋ for the composite oxides with same cation, the power sequence is NO3 OH^-〉CO3^2-〉SO4^2-〉SiO3^2-〉PO4^3- for the haloid with same cation, the power sequence is F^-〉Cl^-〉Br^-. A new catalytic mechanism is proposed., the catalytic effect of a catalyst is attributed to the change of C-C chemical bond by catalyst. The effect of catalysts depends on the kinds of cations and anions and stability of compounds .