(708c) Development of Solid Base Activated Carbon Catalysts for Ketone Condensation and Aviation Fuel Synthesis

Acid hydrolysis and fast pyrolysis of biomass can generate a range of aldehydes (e.g., furfural) and carboxylic acids (e.g., acetic acid). The acids can be converted to linear ketones (e.g., acetone) via catalytic ketonization and furfural to cyclic ketones (e.g., cyclopentanone or CP) via hydrogenation and rearrangement using supported catalysts. Recent work indicates that the bio-derived ketones can be converted to aviation fuel by aldol self-condensation followed by hydrodeoxygenation. The cyclic hydrocarbons derived from self (CP only) or cross (CP+linear ketones) condensation would have high densities and volumetric heating values due to strong ring strain. Studies have shown that anionic clays, particularly hydrotalcites, have a high density of base sites generating higher condensation conversion and yield compared to other catalysts, yet little work has studied hydrotalcite supported catalysts and cross condensation reactions. In this work a Mg/Al-hydrotalcite on activated carbon (AC) catalyst is synthesized and a series of self and cross condensation reactions with acetone and cyclopentanone are studied. It is theorized that the AC support will significantly increase surface area and base active sites and thus increase reaction rates and yields (relative to typical base catalysts). The solid base catalyst could potentially be recoverable, reusable, and used in continuous processing. Results will be presented for a range of reaction conditions and compared to a traditional base catalyst.