Herein we report the synthesis of unsupported bimetallic CoMo and trimetallic CoNiMo sulfide catalysts prepared by thermal decomposition (ex situ activation) of carbon-containing precursors and varying the nickel concentration for the hydrodesulfurization (HDS) of dibenzothiophene. The catalysts prepared were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma mass spectrometry and BET surface area measurements. The results from the characterization showed that the addition of an alkyl chained precursor results in non-porous catalysts with low surface area and high carbon content, which negatively affects the formation of crystalline phases such as molybdenum sulfide and their performance in the HDS reaction. Furthermore, the addition of nickel has a negative effect on the catalysts since it was observed that when it was added, the reaction rate values decreased and the catalyst with the highest catalytic activity turned out to be the CoMo catalyst. Although nickel catalysts generally have more affinity for hydrogenation reactions, unsupported trimetallic catalysts showed a preference for the direct desulfurization pathway.

本文中，我们报告了无载体的双金属CoMo和三金属CoNiMo硫化物催化剂的合成，该催化剂是通过含碳前体的热分解（异位活化）和改变二苯并噻吩加氢脱硫（HDS）的镍浓度而制备的。通过X射线衍射，扫描电子显微镜，透射电子显微镜，感应耦合等离子体质谱和BET表面积测量来表征所制备的催化剂。表征结果表明，烷基链前体的添加导致具有低表面积和高碳含量的无孔催化剂，这不利地影响了结晶相的形成，例如硫化钼及其在HDS反应中的性能。此外，镍的添加对催化剂具有负面影响，因为观察到当添加镍时，反应速率值降低并且具有最高催化活性的催化剂被证明是CoMo催化剂。尽管镍催化剂通常对氢化反应具有更高的亲和力，但未负载的三金属催化剂显示出对直接脱硫途径的偏爱。