Biomass valorization through 5-hydroxymethylfurfural (HMF) oxidation catalyzed by AuPd nanoparticles

Abstract

The concern regarding the exhaustion of oil reservoirs and climate changes has directed the research towards the development of green energy, fuels and chemicals from renewable biomass resources in replacement to the petroleum-derived products. HMF is considered a top-12 biobased chemical, a promising platform compound. Its derivatives are of great importance especially the oxidation products used as biofuels, resins, industrial solvents, bioderived monomers in the polymer industry. The aerobic oxidation of HMF requires several tandem oxidation steps. Another issue is the requirement of an excess amount of a base additive. The chemistry of gold offers unique opportunities in catalysis and excellent alternative for the development of viable industrial processes for conversion of renewable biomass into bio-based chemicals, in particular through oxidation reactions. Au catalysts can offer better resistance to water and O2, however, when alloyed with another metal (e.g., Pd), advantages may be combined and enhance the activity. We have prepared a titanosilicate support in which bimetallic AuPd nanoparticles were encapsulated. The positive alloying effect and the metal-support interaction were effective to provide catalytic activity in absence of base. This research project is part of the current FAPESP process number 2014/10824-3 "Study of gold catalysts for oxidation reactions". The main objectives are the development and optimization of AuPd-based catalytic systems, as an alternative to the use of base, and understand the effect of embedded catalysts over supported ones.