Advances in the study of hydrogen transfer to model compounds for coal liquefaction

The advances in the study of hydrogen transfer to model compounds for coal liquefaction are reviewed, The results from many model reactions indicate t hat molecular hydrogen promotes thermolysis, hydrogenation, and hydrocracki ng of model compounds, whereas hydrogen-donating solvents inhibit the react ions. Unlike metallic catalysts such as Fe, Pd, and Ni, their sulfides cata lyze radical hydrogen transfer to model compounds. The reactivities of mode l compounds toward hydrocracking depend not only on their hydrogen-acceptin g abilities, but also on their adsorption strength on catalyst surface and the stabilities of the resulting leaving groups. (C) 2000 Elsevier Science B.V. All rights reserved.