Kinetic Models of Deep Hydrotreating Reactions to Produce Ultralow Sulfur Diesel

Due to the current worldwide environmentalproblems caused by highemissions of polluting gases such as CO, NO (x) , and SO x , resulting from the combustionof fossil fuels, many organizations and governments have establishedstandards aimed at producing cleaner and more environmentally friendlyfuels. These standards focus on eliminating hazardous substances, particularly the sulfur compounds in diesel, as they are among themost harmful organic compounds to both human health and the environment.Hydrotreating is the main refinery process used to produce ultralowsulfur diesel. For proper modeling and simulation of this process,it is mandatory to develop adequate kinetic models that include allthe reactions taking place during the hydrotreating of gas oil, aswell as the removal of the most refractory compounds present in thechemical composition of diesel, such as 4-MDBT and 4,6-DMDBT. Thiswork reports an exhaustive discussion of the kinetic models of hydrotreatingreactions for the production of ultralow sulfur diesel reported sofar in the literature. The main topics include the reaction systems,type of catalysts, and operating conditions. A comparison of the reportedkinetic parameters was also carried out. Finally, a set of kineticmodels to be considered for the simulation of the hydrotreating processto produce ultralow sulfur diesel is proposed.