We have reported on demonstrated technologies, wherein coal conversion and bio-fuel production could be combined in comprehensive and synergistic ways to provide both a domestic, US, source of renewable liquid fuels, and an inherent method of recycling Carbon Dioxide.
Much has been made, in the United States, of ethanol, derived from corn and other agricultural, renewable and carbon-consuming, sources as a pollution-reducing liquid fuel. Some gasoline vendors blend a small percentage of it into some of their products.
Ethanol alone isn't all that compatible with our current liquid fuel infrastructure, or automotive engine designs, and it really doesn't have the energy density to serve, unblended, as a satisfactory liquid transportation fuel.
It could, however, serve our liquid fuel needs in another way.
Coal that is converted into liquid fuels must be somehow enriched with Hydrogen to form liquid hydrocarbons similar to those that power our current transportation fleet.
A number of supplemental Hydrogen sources have been proposed, and utilized, over the many decades that coal has been converted into liquid transportation fuels: in wartime Germany and Japan, in contemporary South Africa, and in WVU's West Virginia CTL Process, for instance.
As it happens, renewable and CO2-recycling Ethanol can serve as the Hydrogen donor in coal conversion processes, as follows:
"Title
Iron/sulfur-catalyzed coal liquefaction in the presence of alcohol and carbon monoxideAuthors
HATA K.-A.; KAWASAKI N.-A ; FUJI N.; NAKAGAWA Y. ; HAYASHI J.-I; WATANABE Y.; WADA K.; MITSUDO T.-A.Affiliation
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Japan
Abstract
The activities of several iron-based catalyst precursors towards the liquefaction of various kinds of coals, ranging from brown to bituminous, were examined in alcohol-carbon monoxide systems. Pentacarbonyliron (Fe(CO)5) with or without sulfur, or synthetic pyrite were found to be excellent catalyst precursors. Primary alcohols (ethanol and 1-propanol)-CO acted as an effective hydrogen source, whereas branched alcohols were less effective. In the Fe(CO)5/sulfur catalyzed liquefaction of Yallourn coal at 375°C for 120 min, a high conversion (99.5%) was achieved in the presence of ethanol and CO (7.0 MPa/cold). The two-staged reaction (375°C, 60 min + 425°C, 60 min) further improved the oil yield to 59.1% with a slight decrease in the coal conversion. The uptake of alcohol into asphaltene and preasphaltene fractions was distinctly observed, especially for Illinois No. 6 coal. The infrared analyses of the asphaltene fractions from each coal showed absorption at around 1705 cm-', characteristic for those obtained in the linear alcohol-CO systems. According to the characterization of the products by NMR and the preliminary study using a model compound, alkylation as well as the hydrogenolysis seem to contribute to the dissolution of coals."So, Ethanol provides needed Hydrogen and enables a nearly 100% conversion of coal, as in "a high conversion (99.5%) was achieved in the presence of ethanol", into liquid fuels compatible with our current transportation fleet, while helping to recycle Carbon Dioxide.