(40c) Multifunctional Materials for Biomass Conversion to Fuel: A Three-Step Cascade Reaction

Sustainably meeting the growing energy needs of the planet is one of the 21st century’s grand challenges. Global energy demand will increase nearly 60% in the next 25 years. Many pathways to meeting our energy needs while reducing fossil-fuel consumption have been posited, all with challenges. One possible route is to convert biomass into fuels.
In this work, we designed a three-step process that includes hydrogenation of phenol, aldol condensation, and hydrogenation of aldol reaction product to produce fuels from oxygenates using palladium containing dendrons supported on ordered mesoporous silica (OMS). Palladium/dendron-OMS catalyzes the phenol hydrogenation and hydrogenation of aldol coupling products while dendron-OMS without Pd was used for the aldol condensation. 85% yield of cyclohexanone was obtained in the first step (phenol hydrogenation). It is also shown that several aldehydes can be used in Aldol reactions with cyclohexanone, including 4-nitrobenzaldehyde (4-NBA), hydroxymethylfurfural (5-HMF) and benzaldehyde (BA). The aldol products were hydrogenated using Pd/dendron-OMS yielding products not dissimilar from what one observes from aqueous phase reforming (APR). The operating conditions of low temperature and low pressure hydrogen in aqueous media is consistent with green chemistry goals.