Advancing hydrodesulfurization in heavy Oil: Recent developments, challenges, and future prospects

• Published in: Fuel (Guildford) 2024-09, Vol.372, p.132082, Article 132082
• Main Authors: Pham, Duong D., Nguyen, Tung M., Ho, Thi H., Le, Quyet V., Nguyen, Dang L.T.
• Format: Article
• Language: English
• Subjects: Asphaltenes stability; Desulfurization; Heavy oil hydrotreating; Heterogeneous catalyst design; Hydrodesulfurization; Thiophenic sulfur removal
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2024.132082

•Thiophenic compounds condense in heavy oil fractions.•Effective removal of high thiophenic compounds requires a combination of hydrogenation and C-S cleavage.•The efficiency of sulfur removal depends on catalyst, temperature, liquid velocity, and hydrogen pressure.•The main cause of catalyst deactivation is the deposition of coke.•During catalyst regeneration and reactivation, it is important to prevent the formation of high-temperature inert phases. Hydrodesulfurization (HDS) plays a crucial role in refining heavy oil, reducing its sulfur content and enhancing the quality of derived products. This review aims to comprehensively analyze the state-of-the-art in HDS of heavy oil using heterogeneous catalysts. First, we highlight the key challenges associated with this process, including the complex nature of sulfur compounds and the presence of catalyst-deactivating metals and macromolecules. Following this, the review delves into the reaction mechanisms and kinetics of HDS, exploring factors that influence catalyst activity, selectivity, and stability. We provide an in-depth analysis of catalyst characteristics, such as pore structure, active metal type, and metal-support interaction, impact HDS performance. Recent advancements in catalyst design and modification techniques are also discussed. Furthermore, the review addresses the challenges and opportunities related to catalyst regeneration and the development of novel regeneration strategies. Finally, we conclude by providing insights into future research directions and emerging trends in the field of employing heterogeneous catalysts for efficient desulfurization of heavy oil.