(243c) High-Throughput Screening of Hydrodeoxygenation Catalysts

We have constructed a fast pyrolysis reactor for research purposes and are producing bio-oils from mixed softwood flour. Pyrolysis of biomass results in a complex mixture of carboxylic acids, aldehydes, ketones, alcohols, and phenols. The high oxygen content of these compounds results in a low heating value, and the organic acids catalyze polymerization reactions in the mixture which makes long-term storage of the bio-oil problematic. Conventional petroleum hydrotreating is not effective for these oils. Therefore, we are studying catalytic hydrodeoxygenation routes to upgrade them. Thermo-catalytic hydrodeoxygenation of pyrolysis oils remains at a very early stage despite the pioneering efforts of Elliott[1], Bridgwater[2], Delmon[3] and others, so we have been synthesizing new supported catalysts and examining their physical properties and chemical reactivity for this purpose. Such work includes bench-scale hydrodeoxygenation of guaiacol using sulfided metal oxides on novel carbon-supports and mechanistic studies of the selective reduction of acrolein and allyl alcohol on WO3. Initially, we studied catalysts used primarily for oxidation, however now we are focusing our efforts on identifying catalysts that function well for reduction. This talk will describe our work using combinatorial mass spectrometry and microcalorimetry as high-throughput screening methods for identifying new promising catalysts for these applications. The combinatorial screening methodology uses a ten-by-ten array of catalysts deposited by ink-jet techniques on a quartz reaction cell. Microcalorimetric screening is demonstrated using 4-element, calorimetric sensor arrays fabricated by means of traditional photolithography and surface micromachining, and is compatible with the materials deposition techniques used for our combinatorial studies. Results will be presented for hydrogenation of acetone, acrolein, and allyl alcohol over commercial metal oxide catalysts.

1. Elliott, D. C., Historical Developments in Hydroprocessing Bio-oils. Energy & Fuels 2007, 21, 1792-1815.

2. Bridgwater, A. V.; M.Double, J., A strategic assessment of liquid fuels from biomass. In Research in Thermochemical Biomass Conversion, Bridgwater, A. V.; Kuester, J. L., Eds. Elsevier Applied Science: New York, 1988; pp 98-110.

3. Churin, E.; Maggi, R.; Grange, P.; Delmon, B., Characterization and upgrading of a bio-oil produced by pyrolysis of biomass. In Research in Thermochemical Biomass Conversion, Bridgwater, A. V.; Kuester, J. L., Eds. Elsevier Applied Science: New York, 1998; pp 896-909.