Less waste tomorrow thanks to green chemistry

 
Catalysts have dual roles: on the one hand they are capable of promoting chemical reactions, on the other, they can orientate this reaction towards a particular product. Such actions fit in well with green chemistry prerogatives: avoiding intermediate steps, developing more gentle reaction conditions and in particular orientating reactions towards end products, thereby avoiding undesirable intermediaries.

This approach has been used by the Heterogeneous Catalysis group at Lille University to directly convert gaseous methanol, one of the simplest chemicals emitted by the biomass, into dimethoxymethane, a solvent with properties close to those of acetone, widely used in the chemical industry.

The standard reaction generates chemical waste and requires rather extreme reaction conditions. To find an alternative, the Lille group has studied several catalysts: aluminium powders or titanium oxides on which a layer of rhenium oxide has been deposited (active phase), whose properties – notably degree of oxidation- evolve over the course of the reaction.

On the SAMBA beamline, X-ray absorption spectroscopy, set up in Quick-EXAFS mode, has recently made it possible to study the degree of oxidation and the local structure of rhenium, in real time, during the chemical reaction in which the rhenium atoms are participating. Working like this, in operando, is a powerful tool for acquiring greater understanding of how catalysts work and improve their performances. This is a first step towards the production of solvents using plant sources.

Contacts :
Elise.Berrier@univ-lille1.fr
valerie.briois@synchrotron-soleil.fr

Reaction cell for in operando studies