Fundamental hydrogen transfer studies in coal liquefaction: Understanding the answers and questions

摘要

The goal of this research is to quantitatively understand mechanisms of hydrogen transfer pathways between coal-like structures. Understanding the differences between the various hydrogen shuttling mechanisms will yield valuable insight into the fundamental chemistry of coal hydroliquefaction. The authors have combined experimental model compound studies with theoretical approaches to gain a quantitative understanding of the hydrogen transfer process involving donor solvents that promote the scission of strong bonds and prevent retrograde reactions. Mechanistic modeling has been utilized for the development of a global model for predicting rates of bond scission for one-, two- and three-ring diarylmethanes. The model is tested by thermal model compound studies with labeled donor solvents. Ab initio studies have been utilized to obtain activation parameters for the novel radical hydrogen transfer pathway, and semi-empirical methods have been used to investigate trends within families of both hydrogen transfer and hydrogen abstraction pathways.