Fast pyrolysis of lignocellulosic biomass produces a renewable liquid fuel called pyrolysis oil that is the cheapest liquid fuel produced from biomass today. Here we show that pyrolysis oils can be converted into industrial commodity chemical feedstocks using an integrated catalytic approach that combines hydroprocessing with zeolite catalysis. The hydroprocessing increases the intrinsic hydrogen content of the pyrolysis oil, producing polyols and alcohols. The zeolite catalyst then converts these hydrogenated products into light olefins and aromatic hydrocarbons in a yield as much as three times higher than that produced with the pure pyrolysis oil. The yield of aromatic hydrocarbons and light olefins from the biomass conversion over zeolite is proportional to the intrinsic amount of hydrogen added to the biomass feedstock during hydroprocessing. The total product yield can be adjusted depending on market values of the chemical feedstocks and the relative prices of the hydrogen and biomass.

A fuelling success: High‐quality aromatic fuel additives can be produced directly from solid biomass feedstocks by catalytic fast pyrolysis in a single catalytic reactor at short residence times. High heating rates and catalyst‐to‐feed ratios are needed to ensure that pyrolized biomass compounds enter the pores of the ZSM5 catalyst and that thermal decomposition is avoided. Product selectivity is a function of the active site and pore structure of the catalyst.

Catalytic conversion of ten biomass-derived feedstocks, i.e. glucose, sorbitol, glycerol, tetrahydrofuran, methanol and different hydrogenated bio-oil fractions, with different hydrogen to carbon effective (H/C eff ) ratios was conducted in a gas-phase flow fixed-bed reactor with a ZSM-5 catalyst. The aromatic + olefin yield increases and the coke yield decreases with increasing H/C eff ratio of the feed. There is an inflection point at a H/C eff ratio ¼ 1.2, where the aromatic + olefin yield does not increase as rapidly as it does prior to this point. The ratio of olefins to aromatics also increases with increasing H/ C eff ratio. CO and CO 2 yields go through a maximum with increasing H/C eff ratio. The deactivation rate of the catalyst decreases significantly with increasing H/C eff ratio. Coke was formed from both homogeneous and heterogeneous reactions. Thermogravimetric analysis (TGA) for the ten feedstocks showed that the formation of coke from homogeneous reactions decreases with increasing H/C eff ratio. Feedstocks with a H/C eff ratio less than 0.15 produce large amounts of undesired coke (more than 12 wt %) from homogeneous decomposition reactions. This paper shows that the conversion of biomassderived feedstocks into aromatics and olefins using zeolite catalysts can be explained by the H/C eff ratio of the feed.

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In this paper we discuss the continuous flow hydrogenation of the water soluble fraction of bio-oil (WSBO) with Ru/C and Pt/C catalysts. Temparatures higher then 125°C lead to homogeneous reactions within the aqueous phase of bio-oil. Low temperature hydrogenation (LTH) at 125°C over Ru/C catalyst and with WHSV of 1.5-3 hr -1 was required to stabilize the bio-oil so higher temperature hydrogenation (HTH) could occur. The main products from LTH were ethylene and propylene glycols and sorbitol. At these temperatures only small amounts of acetic acid (AA), levoglucosan, furanone, phenol and phenol substitutes were hydrogenated. In the HTH step, the sorbitol was hydrogenated to mono-alcohols and diols by hydrogenolysis and secondary hydrogenation reactions. Up to 45% carbon in WSBO was converted to useful products (gasoline-cuts and diols) in the HTH step over Pt/C catalyst at 250°C and WHSV of 3 hr -1 . The reactions product distribution can be controlled by modifying operating pressure and temperature. The production of gasoline range compounds (C4-C6 alkanes and C1-C6 alcohols) is favoured at low pressure (750 psi). Increasing the reaction pressure decreased the amount of carbon that was converted into gas phase products.

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The cover picture shows a scheme for the conversion of cellulose into gasoline‐range aromatics by catalytic fast pyrolysis. Owing to its recalcitrance, there are currently no economical processes for the direct conversion of lignocellulosic biomass into useful chemicals and fuels. G. W. Huber et al. report in the Communication on a process that they have developed which involves the thermal decomposition of cellulose to smaller volatile oxygenates as the first step. These biomass‐derived species then enter the pores of the zeolite catalyst ZSM5, where they undergo a series of dehydration, decarbonylation, decarboxylation, isomerization, oligomerization, and dehydrogenation reactions that lead to aromatics, including naphthalene, ethylbenzene, toluene, and benzene, and by‐products such as carbon monoxide, carbon dioxide, and water. All this takes place at short residence times (less than 2 min) at 600 °C in a single reactor.

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