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Reactive catalytic fast pyrolysis (RCFP) of biomass with atmospheric pressure hydrogen is a promising route for the deoxygenation of biomass pyrolysis vapors while retaining high carbon yields in the bio-crude. RCFP process development was accomplished in a bench-scale bubbling fluidized-bed reactor with in situ catalyst configuration. Results are presented that highlight the impact of temperature, biomass weight hourly space velocity (WHSV), reaction pressure, and time on stream on the hydrodeoxygenation of different oxygen-containing species produced during biomass reactive catalytic fast pyrolysis to improve the bio-crude product yield and quality. The highest bio-crude and C 4+ hydrocarbons yield was 46.5 wt % on a carbon basis. The optimal temperature range for RCFP is 450−475 °C; the biomass WHSV should be kept low, around 0.6 h −1 in this reactor system, to produce a low oxygen content bio-crude (7.2 wt %), and improvements in the bio-crude yield and quality based on increased pressure are less significant beyond 2.7 bar. The product composition varies by at most 10% for up to 3.5 h' time on stream (biomass-to-catalyst ratio of 2.6 g g −1 ), indicating a stable catalyst activity for hydrodeoxygenation.

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Opuntia ficus-indica (prickly pear) and Grindelia squarrosa (gumweed) are two exceptionally drought tolerant plant species capable of growing in arid and semiarid environments. Additionally, they have unique cell wall structures. Prickly pear contains pectin and high levels of ash (16.1%) that is predominantly Ca and K. Gumweed has high levels of extractives that contain grindelic acid and monoterpenoids. The objective of this paper was to evaluate how these unique cell wall components alter the pyrolysis performance of prickly pear and gumweed. Using a tandem micropyrolyzer with GC-MS/FID/TCD, a detailed account of the product slate is given for products generated between 450 and 650 °C. Pyrolysis of prickly pear showed that the high levels of ash increase the amount of organics volatilized and shifted product pools, making it possible to generate up to 7.3% carbonyls vs 3.8% for Pinus taeda (loblolly pine) and 10.5% hydrocarbons vs 1.8% for pine depending on reaction conditions. Pyrolysis of gumweed showed that the extractives were volatilized at low temperatures and led to 17.7% grindelic acid and monoterpenoids derivatives in the condensed vapor phase. At high temperatures, the extractives and other biomass components are converted to aromatics and C5–C10 hydrocarbons, giving a total yield of 16.6%, and also generate large amounts of C2–C4 hydrocarbons, 11.3%.