Evidence for Autocatalysis and Its Implications for the Kinetics of Hydroprocessing of Petroleum Residues

Abstract

During hydroprocessing of residual feeds the rate of some reactions tends to increase temporarily despite the continuous deposition of coke and metals on catalyst surface. This rate increase has been attributed to catalytic effect of the contaminant metals such as vanadium and nickel in residual feeds after their deposition on catalyst surface. The portion of metals that deposited on the bare γ -Al 2 O 3 surface of the catalysts transfers the originally inactive surface to catalytically active. The increase in the rate of HDS, HDAs, and some HDM reactions could only be reconciled assuming the involvement of autocatalysis by the deposited metals.

Ultraclean Fuels Production and Utilization for the Twenty-First Century: Advances toward Sustainable Transportation Fuels

“…Alternatively, oxidative desulfurization (ODS) using green oxidant H 2 O 2 and novel methods based on photochemistry, electrochemistry, biochemistry are also intensively investigated as important directions for ultradeep desulfurization. During the symposium of “Ultraclean Fuels Production and Utilization”, all of these topics related to desulfurization were presented from the modification of the HDS catalyst, the application of ionic liquids and magnetic nanocatalyst for ODS, − to the replacement of molecular hydrogen with “ in situ ” hydrogen . It cannot be denied that significant improvements in process engineering and deep understandings on catalytic science have been made for the ultradeep desulfurization process.…”