清华大学李亚栋团队报道了利用热雾化回收含硫钯催化剂用于乙炔半加氢。相关研究成果发表在2024年11月11日出版的《美国化学会杂志》。

钯催化剂对于各种化学工业过程都是高效的，但在实际应用中容易受到毒物的影响。硫是钯基催化剂中的主要毒物之一。由于Pd-S键很强，因此回收深度中毒的Pd物种（如Pd硫化物）具有挑战性。

该文中，研究人员提出了一种自上而下的策略，通过一步热原子化降解Pd硫化物并同时产生Pd单原子位点。

将Pd4S模型纳米粒子负载在ZIF-8上并进行热处理后，成功转化为负载在氮硫共掺杂碳（Pd1/N,S-C）上的Pd单原子位点。在雾化过程中形成PdZn中间体。

密度泛函理论表明，PdZn的形成有助于金属纳米粒子附近空位的产生，从而促进了原子化过程。

该策略可以很容易地应用于硫中毒的商用Pd/C的雾化，表明了回收商用催化剂的潜力。最佳Pd1/N,S-C催化剂在乙炔半加氢反应中，表现出良好的活性和比Pd4S高得多的选择性。

附：英文原文

Title: Recycling Sulfur-Poisoned Pd Catalysts via Thermal Atomization for Semi-Hydrogenation of Acetylene

Author: Qiheng Li, Shoujie Liu, Jin-Cheng Liu, Zhi Li, Yadong Li

Issue&Volume: November 11, 2024

Abstract: Palladium catalysts are highly efficient for a variety of chemical industrial processes but are prone to being affected by poisons during practical application. Sulfur is one of the major poisons in Pd-based catalysts. The recycling of deeply poisoned Pd species like Pd sulfides is challenging due to the strong Pd–S bond. Herein, we proposed a top-down strategy to degrade Pd sulfides and create Pd single-atom sites simultaneously by one-step thermal atomization. Pd4S model nanoparticles were successfully converted to Pd single-atom sites supported on nitrogen and sulfur-codoped carbon (Pd1/N, S–C) after loading them on ZIF-8 and thermal treatment. PdZn intermediates were formed during the atomization process. Density functional theory revealed that the formation of PdZn helped the generation of vacancies adjacent to metal nanoparticles, which prompted the atomization process. This strategy can be facilely applied to the atomization of sulfur-poisoned commercial Pd/C, which shows the potential for recycling commercial catalysts. The optimal Pd1/N, S–C catalyst showed good activity and much enhanced selectivity than Pd4S for the semi-hydrogenation of acetylene.

DOI: 10.1021/jacs.4c11305

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c11305