Mesoporous silica FSM-16 catalysts modified with various oxides for the vapor-phase Beckmann rearrangement of cyclohexanone oxime
Mesoporous silica FSM-16 catalysts modified with various oxides for the vapor-phase Beckmann rearrangement of cyclohexanone oxime
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DOI：
10.1016/s0926-860x(99)00519-0
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发表时间：
2000-05
影响因子：
5.5
通讯作者：
D. Shouro;Yuki Moriya;T. Nakajima;S. Mishima
中科院分区：
文献类型：
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作者：
D. Shouro;Yuki Moriya;T. Nakajima;S. Mishima
制备了不同氧化物改性的介孔SiO2 FSM-16催化剂，测定了催化剂的酸碱性质，并将其用于环己酮肟的气相Beckmann重排反应。用碱性指示剂吸附法和乙胺程序升温脱附法测定了催化剂的酸碱性质。通过负载Al_2O_3、ZnO和CdO提高了FSM-16的α-己内酰胺选择性。研究发现，乙胺吸附热约为135 kJmol-1的酸中心可有效提高ε-己内酰胺的选择性。另一方面，催化剂的失活随着强碱性中心的量的增加而更快地进行。结果表明，氧化物改性是提高FSM-16催化环己酮肟气相Beckmann重排反应性能的有效方法。
Mesoporous silica FSM-16 catalysts modified with various oxides have been prepared, subjected to measurement of acid–base properties, and applied as a catalyst to the vapor-phase Beckmann rearrangement of cyclohexanone oxime. Acid–base properties of the catalysts were measured by the basic indicator adsorption method and the temperature-programmed desorption (TPD) of ethylamine. The ϵ-caprolactam selectivity of FSM-16 is improved by supporting Al2O3, ZnO and CdO. It was found that acid sites with the heat of adsorption of ethylamine around 135kJmol−1are effective to increase ϵ-caprolactam selectivity. On the other hand, deactivation of the catalysts proceeds more rapidly with increase in the amount of strong basic sites. It is concluded that modification of FSM-16 by oxides is an effective method of improving the catalytic properties of FSM-16 for the vapor-phase Beckmann rearrangement of cyclohexanone oxime.