碳纳米管负载Pt-Sn-B非晶态催化剂催化氯代硝基苯

 用浸渍-化学还原法制备了碳纳米管负载的Pt-Sn-B非晶态催化剂,并采用透射电子显微镜、X射线衍射、选区电子衍射、X射线能谱等表征手段研究了催化剂在碳纳米管表面的存在状态、组成及其非晶性质. 将此催化剂用于三种氯代硝基苯的液相催化加氢反应,结果表明该催化剂具有较好的加氢性能和较高的抑制脱卤性能. 在不添加脱卤抑制剂的情况下,三种氯代硝基苯的转化率均高于99.8%,脱卤率小于1.9%. 而将通用加氢催化剂用于相同的反应时,产物的脱卤率均高于8%. 碳纳米管的特殊结构与表面金属的非晶性质是影响氯代硝基苯加氢性能的主要因素. 讨论了碳纳米管与表面非晶态金属的作用规律及其与催化加氢性能的关系.

Catalytic Performance of Pt-Sn-B Amorphous Catalyst Supported on Carbon Nanotubes for Liquid-Phase Hydrogenation of Chloronitrobenzene

The Pt-Sn-B/carbon nanotubes (CNTs) catalyst was prepared by impregnation-chemical reduction method. Its catalytic performance was evaluated by liquid-phase hydrogenation of chloronitrobenzene. The results showed that this catalyst had higher catalytic performance than common hydrogenation catalysts. The conversion of chloronitrobenzene reached 99.9% and the dechlorination of chloroaniline was less than 1.9% when catalyzed by Pt-Sn-B/CNTs, while the dechlorination of chloroaniline was more than 8% when catalyzed by common hydrogenation catalysts. XRD and selected area electron diffraction analysis showed that Pt-Sn-B/CNTs had amorphous alloy structure which could improve the catalytic performance. TEM image showed that the catalyst particles were highly distributed on the surface of CNTs. The hydrodechlorination of chloronitrobenzene was mainly affected by the unique structure of CNTs and the nature of amorphous metals on the surface of CNTs. The relationship between the interaction of CNTs and amorphous metals and the catalytic performance of the catalyst was discussed.