Using natural and renewable raw materials, instead of petroleum oil derivatives, is nowadays a must for the chemical industry, not only because of newly appeared environmental legislations, but also because of the growing societal awareness of the necessity to shift towards more environment-friendly processes.In this context, oleochemistry currently receives regaininginterest. This domain aims at producing a large variety of valuable chemicals such as long-chain fatty acids and their esters, fatty alcohols, glycerine, alcanolamides, stearates, surfactants, etc, from animal fats and either vegetable or food-industry waste oils.
In terms of reactions, transesterifications and esterifications are of primary importance for oleochemistry. Often, these reactions are carried out via homogeneous catalytic processes, either using dissolved mineral acids (as sulphuric acid) or soluble bases (as sodium methanolate). Although efficient in term of productivity, these processes suffer from the drawbacks of homogeneous catalysis : necessary down-stream removal of the catalysts from the products,need of corrosion-resistant reactors, and restriction to batch mode processes.
This project aims at the intensification of oleochemical processes by developing innovative heterogeneous catalysts (solids remaining undissolved during the whole chemical reaction) suitable for transesterifications and esterifications. Monolith type catalysts will eventually also be envisaged, so as to allow performing the concerned processes in uni-directional flow catalytic continuous reactors.
Specifically, three families of catalysts will be investigated : 1- a hybrid enzymatic-inorganic family, 2- a macrocellular foam, and 3- heteropolyacid compounds entrapped in a macroporous matrix.
The thesis will specifically aim at optimizing the synthesis of the catalysts in order to maximize their activity, selectivity and recyclability. This last aspect is crucial as it is related to the necessity to develop materials from which the active species should not suffer any leaching in the reaction medium. Another feature of the catalysts that the thesis will optimize concerns their porosity. As reactions in liquid phase are here considered, it is essential that the pores in the catalysts are big enough to prevent diffusion limitations - that would be detrimental on the process efficiency – and optimize mass transport.
Next to the triangular correlation between textural features of the catalysts vs resistance of the active species to leach vs accessibility of the active species and performances, another deliverable of the thesis is to establish a correlation between the nature of the active species vs their acidity vs activity and selectivity of the catalysts.
The preparation of the catalysts will be made in Bordeaux (families 1- and 2-) and in Louvain-la-Neuve (family 3-), along with their physico-chemical characterization by the several techniques available at the academic partners.
Mosselman s.a. is a belgian medium company active in oleochemistry. The involvement of the company in the project is envisaged in two ways. 1- Measurements of the performances of the most promising catalysts will be made with real industrial charges provided by Mosselman. 2- In case of ascertained transferability, the efficiency of the process would be evaluated at the pilot scale.
University partner 1: UCL:
Eric GAIGNEAUX, Université catholique de Louvain, Institute of Condensed Matter and Nanosciences (IMCN), Division “Molecules, Solids & reactiviTy” (MOST), Louvain-la-Neuve (Belgium). Relevant competences for the project : catalysts preparation, sol-gel chemistry, heteropolyacids, physicochemical characterization of solid catalysts, catalytic activity measurements.
Damien DEBECKER, Université catholique de Louvain, Institute of Condensed Matter and Nanosciences (IMCN), Division “Molecules, Solids & reactiviTy” (MOST), Louvain-la-Neuve (Belgium), currently in post-doc at Université Pierre et Marie Curie, Paris (France). Relevant competences for the project : catalyst preparation (impregnation, sol-gel, aerosol), catalytic activity measurements, bio-catalysis, synthesis of bio-inorganic hybrids, physico-chemical characterization of solid catalysts.
University partner 2 : UB1
Rénal BACKOV, Université de Bordeaux 1, Centre de Recherche Paul Pascal (CRPP), Bordeaux (France). Relevant competences for the project : sol-gel chemistry, hybrid materials, physical chemistry of complex fluids, integrative chemistry, heterogeneous catalysis, characterization of porous matter at various length scales.
Industry partner :
Mosselman s.a., route de Wallonie 4, Ghlin (Belgium). Relevant competences for the project : esterification and transesterification process on lab, pilot and industrial scale, analytical evaluation of vegetable oils and fatty esters, commercial evaluation (specifications).