Changes in the oxidation state and chemical environment of vanadium in poisoned and regenerated hydrotreatment (HDT) catalyst were followed by electron paramagnetic resonance (EPR). Oxovanadyltetraphenil porphyrin was used as model poison molecule on synthesized CoMo/Al₂O₃ HDT-UCV-1 catalyst. Unconventional methodologies of carbiding and nitriding were applied to the deactivated catalyst aiming at recovering its catalytic properties. The results showed that the vanadium incorporation method affected the metallic species on the catalyst surface, particularly the V-support interaction. This work represents an important contribution about the understanding of new phases formed in the spent catalysts after reactivation by means of nitriding and carbiding processes, which are expected to improve the catalytic HDT response.

中文翻译：

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电子顺磁共振研究中毒加氢脱硫催化剂中钒的电子变化经历氧化，碳化和氮化过程

中毒和再生加氢处理（HDT）催化剂中钒的氧化态和化学环境的变化随后是电子顺磁共振（EPR）。氧钒基四苯菲卟啉用作合成的CoMo / Al ₂ O _3的模型毒物分子HDT-UCV-1催化剂。碳化和氮化的非常规方法应用于失活催化剂，旨在恢复其催化性能。结果表明，钒的引入方法影响了催化剂表面的金属种类，特别是V-载体的相互作用。这项工作代表了对通过硝化和碳化工艺在活化后的废催化剂中形成新相的理解的重要贡献，这些新相有望改善催化的HDT反应。