Novel inorganic oxides for biomass conversion
Rapid depletion of fossil fuel reserves for production of transportation fuels, energy and chemicals necessitate their replacement by renewable, environmentally friendly alternatives such as biomass. Cellulose makes up the brunt of lignocellulosic biomass (obtainable from agricultural waste, wood, etc.) and is essentially a glucose polymer. Depolymerization of cellulose thus yields glucose which can potentially be upgraded to several platform molecules. Examples are levulinic acid, 5-hydroxymethylfurfural (5-HMF) and lactic acid which all have an extensive range of applications. Current oil-based catalytic systems are generally unsuitable for biomass conversion, and as such requires development of novel, highly tunable catalysts.
Successful biomass conversion depends on a number of crucial factors, such as solvent systems, reaction conditions and the nature of the catalyst. Varying these conditions alters the activity and selectivity towards the desired products. Central to these transformations are the number and strength of the Lewis and Brønsted acid sites provided by the catalyst. Tungsten oxide, known for its Lewis and mild Brønsted acidity, has shown significant activity towards glucose conversion into 5-HMF, but the system presents ample room for improvement. Brønsted acidity was successfully enhanced by incorporation of promotor metals such as niobium and titanium. Further advancements in activity were found after increasing the available surface area and mesoporosity of the catalyst.
We believe that the activity of the system can be further tuned by altering reaction conditions, varying promotor concentrations in the surface-enhanced material and studying the formation of a structured mesoporous system in the catalyst.
- Synthesis and application of mesoporous promoted tungsten oxides of varying tungsten to promotor ratios, and characterization of these materials by XRD, TGA, TEM, XPS, ICP-AES, etc. followed by activity tests on glucose conversion to 5-HMF under various reaction conditions and analysis of reaction mixtures by physo-chemical methods like HPLC, MS and GC.
For further information:
Emiel Hensen (Helix, STW 3.35, Tel 5178, e.j.m.hensen@) tue.nl
Nico Sommerdijk (Helix, STO 2.30, Tel 5870, n.sommerdijk@) tue.nl
Jan Wiesfeld (Helix, STW 3.31, Tel 2122, firstname.lastname@example.org)