The introduction of renewable carbon (biomass, CO₂, waste) in the chemical industry raises scientific and technological challenges, requiring chemists to re-invent chemistry. Although much efforts have been done so far, the emergence of biobased chemicals in our society still remain difficult due to scientific, environmental and societal hurdles. Emergence of biobased chemicals on the market is mostly driven by their intrinsic performances. In this context, our strategy consists in taking advantage of the chemical functionalities existing in biomass waste in order to bring novel properties that are hardly obtainable from fossil feedstocks. In all these chemical transformations, catalysis is placed at the heart of our strategy, in particular with the aim of finely controlling or tuning the reaction selectivity, while improving the space time yield of catalytic reactors. The catalytic control of the reaction selectivity is scientifically difficult to achieve with biobased molecules, essentially due to their polyfunctionality. Usually, to overcome this problem, most of these biobased catalytic routes are explored under diluted conditions (< 5 wt% in water) to limit the formation of tar-like materials which rapidly deactivate solid catalysts. Unfortunately, under diluted conditions, low space time yields are obtained, hampering the implementation of these catalytic reactions on a larger scale. Being able to catalytically convert, and selectively, concentrated feeds of biobased molecules is an important but very difficult scientific task, which is addressed in our researches.

In this context, we are developing two different strategies:

• The coupling of catalysis with alternative technologies such as high frequency ultrasound, milling or non-thermal atmospheric plasma. In this scientific strategy, a synergistic effect between catalysis and those alternative technologies is researched in order to selectively drive a series of elementary reactions to a targeted chemical. One of the main objectives consist in the identification and the understanding of the physical and chemical phenomena involved, the characterization of exited species formed in situ, the interaction of those species with organic chemicals and/or catalytic surfaces, their diffusion and stability in a liquid or at the surface of a catalyst, etc. This scientific strategy has allowed us to make advance the state of the art in the selective oxidation of carbohydrates, in the depolymerization of recalcitrant biopolymers such as cellulose and in the synthesis of biobased building blocks such as levoglucosane, oligosaccharides, etc.

  

  • The design of active and water tolerant catalysts. This research theme is performed in strong interaction with other teams involved in DFT calculations. These joint investigations led us to rationalize and, more importantly, to predict in some cases the chemical reactivity of biobased chemicals, a strategy that has paved the way to different chemical platforms. These investigations led us to conceive more performant bifunctional catalytic systems allowing (1) converting selectively concentrated feeds of biobased substrates into specialty chemicals, (2) performing selective cascade reactions in a single catalytic reactor and (3) improving the space time yield of catalytic reactions. These works are typically applied in the synthesis of biobased amines and aromatics from various renewable substrates, in particular furfural.