硫掺杂碳材料负载铂族金属催化性能逆规律特殊现象的揭示

The complexes weakly bonded by supported platinum group metal atoms and sulfides are commonly used to improve the selectivity of catalytic hydrogenation. However, the high reaction temperature and strong exotherm in the reaction micro region lead to the leaching of the sulfide, which contributes to a poor stability of the catalyst. We found that sulfur doped carbon-supported platinum group metals exhibited a better stability. Moreover, an abnormal law was observed that the catalytic hydrogenation activity decreased with the decreasing of the metal particle size. The mechanism of sulfur doped carbon-supported platinum group metal catalysts in the selective hydrogenation has not been explored and explained yet. In this project, three basic problems will be resolved: 1) the doping mechanism of sulfur content, valence and structure controlling during the preparation of sulfur doped carbon materials; 2) the effect of sulfur doping on the morphology and electronic band properties of platinum group metal particles; 3) the catalytic mechanism of sulfur doped carbon-supported platinum group metals in the selective hydrogenation. Through this project, we can establish an important theoretical foundation for the development of the selective hydrogenation catalyst and technology.

负载型铂族金属原子与硫化物以弱键合形成复合物常被用于提高催化加氢选择性，但高温反应过程中存在加氢反应微区强放热，造成弱键合的硫化物易流失，导致催化剂稳定性下降。本项目提出通过碳材料中掺杂硫元素再负载铂族金属试行替代弱键合的复合物，达成催化加氢反应稳定的高选择性。申请者前期工作发现该体系催化剂的加氢活性随金属粒径减小而降低的逆规律特殊现象。目前对硫掺杂碳材料负载铂族金属催化剂在选择性加氢反应中的作用机制尚缺乏深入研究。本项目拟解决以下三个基础问题：1）硫掺杂碳材料制备过程中控制硫掺杂位点、含量和基团类型的掺杂机理；2）碳材料掺杂硫对负载铂族金属粒子形貌和电子能带特性的影响规律与作用机制；3）硫掺杂碳材料负载铂族金属催化剂在选择性加氢反应中的催化机理。本项目的开展并顺利完成，将为选择性加氢催化剂与工艺的开发奠定良好的理论基础。

负载型铂族金属原子与硫化物以弱键合形成复合物常被用于提高催化加氢选择性，但高温反应过程中存在加氢反应微区强放热，造成弱键合的硫化物易流失，导致催化剂稳定性下降。本项目提出通过碳材料中掺杂硫元素再负载铂族金属试行替代弱键合的复合物，达成催化加氢反应稳定的高选择性。本项目发现该体系催化剂的加氢活性随金属粒径减小而降低的逆规律特殊现象。目前对硫掺杂碳材料负载铂族金属催化剂在选择性加氢反应中的作用机制尚缺乏深入研究。本项目解决以下三个基础问题：1）硫掺杂碳材料制备过程中控制硫掺杂位点、含量和基团类型的掺杂机理；2）碳材料掺杂硫对负载铂族金属粒子形貌和电子能带特性的影响规律与作用机制；3）硫掺杂碳材料负载铂族金属催化剂在选择性加氢反应中的催化机理。本项目为选择性加氢催化剂与工艺的开发奠定良好的理论基础。