A dispersed molybdenum catalyst, derived from MoO 2 (acac) 2 (where acac ) acetylacetonate), was used for upgrading extra-heavy crude oil in the presence of methane as source of hydrogen. The experiments were carried out in a batch reactor at a final CH 4 pressure of 11 MPa, 410 °C, for 1 h. An increase of 7°in the API gravity, 16% of reduction in sulfur content, and 55% conversion of the >500 °C fraction with respect to the original crude was found. The catalyst was analyzed by XPS and EDAX from the coke isolated from the upgrading reaction and it was confirmed that molybdenum is present as MoS 2 . By XPS and SIMS, mechanistic studies were carried out using MoS 2 synthesized on a pure molybdenum sheet. A mechanism for addition of the methane to crude oil is proposed which involves activation of CH 4 by the MoS 2 catalyst generating CH x and H 4-x species on the catalyst surface (where x ) 1, 2, or 3). The CH x moiety can be added to the hydrocarbon molecules, forming methylated products. By carbon isotope ratio mass spectrometry analysis, labeled methane ( 13 CH 4 ) was found to incorporate into the crude oil (estimated value 0.01% w/w) giving conclusive evidence on the involvement of CH 4 in the heavy crude oil upgrading processes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.