Aqueous-phase reforming of ethylene glycol over alumina-supported Pt-based catalysts is reported. Performance of the catalysts is investigated by conducting kinetics and in situ attenuated total reflectance (ATR)-IR spectroscopic analysis. Pt/γ-Al2 O3 is unstable under APR conditions (270 °C, 90 bar) and undergoes phase transformation to boehmite [AlO(OH)]. This conversion of alumina is studied in situ by using ATR-IR spectroscopy; transition into boehmite proceeds even at milder conditions (210 °C, 40 bar). Pt/γ-Al2 O3 deactivates irreversibly because the Pt surface area decreases owing to an increasing metal particle size and coverage with boehmite. However, Pt supported on boehmite itself shows stable activity. Surprisingly, the rate of formation of hydrogen per Pt surface atom is significantly higher on boehmite compared to an alumina-supported catalyst. This observation seems correlated to both increased concentration of surface OH groups as well as to enhanced oxidation of Pt when comparing Pt/γ-Al2 O3 with Pt/AlO(OH).

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Generation of chemicals from renewable bio-based feedstocks often involve a hydrogenation step. In order to make these conversions completely green, it is essential that the required hydrogen for this is also made available from bio feedstocks. Byproducts of bio-based processes are typical for this. Examples of such scenarios are outlined to justify their choice. Waste/byproduct bio-feedstocks available for hydrogen production are often dilute aqueous streams. This chapter addresses the current status and issues involved in the production of hydrogen via catalytic aqueous phase reforming of such streams.