Recent Advances in Hydrotreating/Hydrodesulfurization Catalysts: Part II—Catalyst Additives, Preparation Methods, Activation, Deactivation, and Regeneration

Additives play a key role in enhancing the activity of hydrotreating catalysts by means of influencing metal–support interactions, improving dispersion of active metals on the support, enhancing the sulfidation degree, increasing stacking of metal sulfide slabs on the support, etc. Additives are also reported to enhance the stability of the catalysts apart from modifying their activity. Another aspect of hydrotreating catalyst manufacture is the method of preparation of these catalysts, which will influence the metal dispersion, support interactions, and ultimately the performance. The present chapter (Part II) reviews the recent advances in hydrotreating/hydesulfurization catalysts in terms of additives/modifiers and various preparation methods. Other aspects of catalysts such as activation, deactivation, and regeneration are also being discussed upon. Apart from this, catalyst requirements for different hydrotreating feedstocks have also been covered, considering the importance of feedstock type and characteristics on the selection of suitable catalysts.