Deactivation of Heavy Oil Hydroprocessing Catalsyts deals with a topic of current and future relevance: the loss of activity of catalyst activity during hydroprocessing of heavy oils. Firstly, the main physical and chemical properties of heavy oils, which affect catalyst life, are discussed in detail. All the main properties of hydroprocessing catalysts that are affected when dealing with heavy oils are also described. The different mechanisms of catalyst deactivation, e.g. deactivation by coking, deactivation by metals deposition, and pore constriction, are addressed.. Characterization of fresh, spent and regenerated catalysts by a wide variety of experimental techniques and reaction conditions during hydroprocessing is discussed. Various approaches reported in the literature for modeling the catalyst deactivation, particularly for hydroprocessing of heavy oils, are described and analyzed. The development of correlations and models is thoroughly described with the aid of detailed experimental data collected from different reaction scales. Experimental data, explanations of how to determine model parameters, rigorous treatment of the different topics as well as the step-by-step description of the models formulation and application, make this book an indispensable reference not only for professionals working in the development of catalyst and models for the petroleum industry, but also as a supplementary textbook for courses in chemical reaction engineering.