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A mechanism is proposed for catalysis of the water-gas shift reaction by basic aqueous solutions in a pressurized reactor. The mechanism is proposed as a cyclic system with three intermediate anions: carbonate, hydroxide, and formate. A carbonate ion reacts with water to form hydroxide and carbon dioxide. The hydroxide ion reacts with carbon monoxide to generate formate Ion. The formate decomposes to carbonate and formaldehyde which in turn generates hydrogen by decomposition. This mechanism can proceed in the presence of any basic catalyst precursor which generates one of the three catalytic species. A study of the formate/carbonate equilibrium was made, as well as catalyst concentration studies.

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Experimental results are reported for high-pressure liquefaction of high-moisture biomass. The feedstocks included macrocystis kelp, water hyacinths, spent grain from a brewery, grain sorghum field residue and napier grass. The biomass was processed in a batch autoclave as a ten weight percent slurry in water with sodium carbonate catalyst and carbon monoxide gas. Thirty-minute experiments were performed at 350°C with operating pressures ranging from 270 to 340 atmospheres. The oil products were collected by methylene chloride and acetone extractions. Oil yields ranged from 19 to 35 mass percent on a moisture and ash-free basis. The oil products contained from 9.9 to 16.7 percent oxygen with hydrogen to carbon atomic ratios from 1.36 to 1.61. Significant nitrogen content was noted in the oil product from those feedstocks containing nitrogen (kelp, hyacinth, spent grain). Chemical composition analysis by gas chromatography/mass spectrometry demonstrated many similarities between these products and wood-derived oils. The nitrogen components were found to be mainly saturated heterocyclics.Significant progress has been made over the past fifteen years toward the development of processes for direct production of liquid fuels from biomass. Process research has generally progressed along two lines -flash pyrolysis and high-pressure processing. Extensive analysis of the liquid products from these two types of processes has demonstrated the significant process-related differences in product composition. However, the effect of feedstock has received a lesser degree of attention.