Refining coal liquids: Where we stand

In extensive studies sponsored by the US Department of Energy, syncrudes from a variety of coals (bituminous, sub-bituminous, lignite) and several direct coal-liquefaction processes (SRC-II, H-Coal, EDS, ITSL) were catalytically hydroprocessed in pilot plant tests. The results show that these syncrudes can be refined to transportation fuels (diesel, jet fuel, gasoline) using commercial petroleum hydroprocessing technology. Key factors that determine how easy or difficult a particular syncrude is to refine are boiling range (endpoint), hydrogen content, and heteroatom content. This paper reviews experimental results, discusses alternative refining routes, compares projected costs for these routes with different feeds, and identifies areas in which further research is needed.