Research

The Laboratory of Sustainable and Catalytic Processing is generally interested in making processes and the chemicals they produce greener and more sustainable. Several active areas of investigation are described below.

 

Biomass deconstruction and protection group chemistry

Biomass deconstruction is the initial process that aims to depolymerize the major plant biopolymers such as cellulose, hemicellulose (i.e. polysaccharides) and lignin (a heteropolymer of phenylpropanoid subunits) to their constituent molecules. Lignin has attracted less interest because it is easily destroyed during pulp and paper processing and most biorefinery processes. Our group is developing protection group chemistry to avoid lignin destruction during extraction and have recently been able to produce extracted soluble lignin that can be upgraded at near theoretical yields. We are also study organic solvent effects and enzymatic hydrolysis models to try to improve and better understand the underlying mechanisms of biomass pretreatment and subsequent enzymatic hydrolysis.

Lignin NMR     

 Stabilized Lignin

Researchers involved in this work: Dr. Wu Lan, Masoud Talebi, Ydna Questell-Santiago and Jessica Rohrbach.

W. Lan, M. T. Amiri, C. M. Hunston, and J. S. Luterbacher*. “Protection group effects during α,γ-diol lignin stabilization promote high-selectivity monomer production”. Angew, Chem. Int. Ed., 57: pp. 1356–1360, 2018. doi: 10.1002/anie.201710838

L. Shuai, M. T. Amiri, Y. M. Questell-Santiago, F. Héroguel, Y. Li, H. Kim, R. Meilan, C. Chapple, J. Ralph, and J. S. Luterbacher*. “Formaldehyde stabilization facilitates lignin monomer production during biomass depolymerization”. Science, 354 (6310): pp. 329–333, 2016. doi: 10.1126/science.aaf7810.

L. Shuai and J. Luterbacher*. “Organic Solvent Effects in Biomass Conversion Reactions”. ChemSusChem, 9 (2): pp. 133–155, 2016. doi: 10.1002/cssc.201501148.

 

 

Catalytic reforming of biomass and fermentation-derived molecules to fuels and chemicals

As Switzerland and the rest of the world searches for alternatives to fossil resources, biomass is an attractive feedstock for renewable fuels and chemicals. This is especially the case for fossil-based products that cannot be easily substituted with alternatives such as renewable electricity. In this context, fermentation-derived molecules (carboxylic acids, succinic acid, lactic acid…), lignin-derived aromatics, and carbohydrate-derived furans and acids are attractive candidates for catalytic reforming for the production of targeted fuels and chemicals. We are also exploring the upgrading of low value biomass such as sewage sludge to valuable inorganic streams and methane. Various catalytic routes are being explored to convert all these products to new platform chemicals or direct replacement for currently used petrochemicals.

      Catalytic routes

Researchers involved in this work: Jher Hau Yeap and Dr. Gael Peng.

Also, check out our start-up that is involved in sewage-sludge valorization.

Recent summary reviews:

F. Héroguel, B. Rozmysowicz, and J. S. Luterbacher*. “Improving Heterogeneous Catalyst Stability for Liquid-phase Biomass Conversion and Reforming”. CHIMIA International Journal for Chemistry, 69 (10): pp. 582–591, 2015. doi: 10.2533/chimia.2015.582.

 

 

Catalyst synthesis for renewable molecule production

There is an urgent need to provide these cheap, stable, selective, and highly active catalysts for renewable molecule production. Renewable biomass-derived molecules, unlike those produced from petroleum are highly oxygenated, and often produced in dilute-aqueous streams. Heterogeneous catalysts – the workhorses of the petrochemical industry – are sensitive to water and contain many metals that easily sinter and leach in liquid-phase conditions. The production of renewable chemicals from biomass, especially valuable aromatics, often requires expensive platinum group metals and suffers from low selectivity. Overcoated copper oxide

    Overcoated Cu on Alumina

New synthetic methods based on catalyst overcoating present potential solutions to this problem. At LPDC, we are working on synthesis methods to precisely control surface functionalities of heterogeneous catalysts by the deposition of highly tailored metal oxide overcoats with sub-nanometer precision. Initial work show that our overcoats can eliminate irreversible deactivation of catalysts used in liquid phase conditions and greatly increase selectivity by creating active sites at the interface of metal, support and overcoat.

 Overcoated SBA-15

Researchers involved in this work: Dr. Florent Héroguel, Benjamin Le Monnier and Yuan Peng Du.

Recent work and summary reviews:

F. Héroguel, L. Silvioli, Y.-P. Du and J. S. Luterbacher. “Controlled deposition of titanium oxide overcoats by non-hydrolytic sol gel for improved catalyst selectivity and stability”. Journal of Catalysis, 358: pp. 50–61, 2018. doi: 10.1016/j.jcat.2017.11.023

F. Héroguel, B. P. Le Monnier, K. S. Brown, J. C. Siu, and J. S. Luterbacher. “Catalyst stabilization by stoichiometrically limited layer-by-layer overcoating in liquid media”. Applied Catalysis B: Environmental, 218: pp. 643–649, 2017. doi: 10.1016/j.apcatb.2017.07.006.

F. Héroguel, B. Rozmysowicz, and J. S. Luterbacher*. “Improving Heterogeneous Catalyst Stability for Liquid-phase Biomass Conversion and Reforming”. CHIMIA International Journal for Chemistry, 69 (10): pp. 582–591, 2015. doi: 10.2533/chimia.2015.582.

 

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Photos: Alain Herzog and Jeremy Luterbacher EPFL