Asphaltenes diffusion/adsorption through catalyst alumina supports − influence on catalytic activity

Publication date: Available online 18 October 2017 Source:Catalysis Today Author(s): Bertrand Guichard, Florine Gaulier, Jérémie Barbier, Thibaut Corre, Jean-Louis Bonneau, Pierre Levitz, Didier Espinat Refining heavy or extra heavy oil is still an important challenge for petroleum chemistry. The research performed in the field of hydroprocessing technologies covers different sides of the domain laying from the reactor and process aspects to heterogeneous catalysts development. Historically, at a large scale of time, the worldwide trend seems to indicate a decline of light conventional crude oil availability, the latest being gradually replaced by heavier non-conventional resources that contain asphaltenes and high concentrations of nitrogen and sulfur compounds. It emphasizes the need for conversion of the heaviest feeds and for improving the corresponding refining catalysts. One point raised here to progress deals with the role of the support (alumina), peculiarly about the role of the nanoporous texture on the accessibility of the feedstock molecules to the active sites. Among these large molecules to be considered, asphaltenes play a major role and are often pointed out to be responsible for the industrial issues: plugging porosity, coking support and metal sulphide active phase, poisoning hydrogenating metal. The macrostructure of asphaltenes is complex, characterized by a multi-scale aggregation behavior, strongly influenced by environmental parameters, as fo...
Source: Catalysis Today - Category: Chemistry Source Type: research