Laboratoire des procedes durables et catalytiques

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Green solvents for chemical reactions

Jeremy Luterbacher

The present invention relates to Use of a compound of the general formula (I), (II), (III), (IV), (V) or (VI) wherein R1 and R1', R21 and R21', R31 and R31' are the same and are hydrogen, a linear or branched C1 to C18 alkyl, a linear or branched C2 to C18 alkenyl, a linear or branched C1 to C10 alkoxy, a linear or branched C1 to C9 alkoxycarbonyl, a linear or branched C1 to C9 alkanoyloxy, aminocarbonyl, hydroxycarbonyl, a linear or branched C1 to C9 alkoxyalkyl, an unsubstituted cycloalkyl, a linear or branched C1 to C6 alkyl substituted cycloalkyl, preferably an unsubstituted cyclohexyl, an unsubstituted C6 to C12 aryl, a linear or branched C1 to C4 alkyl substituted C6 to C12 aryl, or C7 to C12 aralkyl, R2 and R2', R22 and R22', R32 and R32' are the same and are hydrogen, a linear or branched C1 to C18 alkyl, a linear or branched C1 to C9 alkoxyalkyl, or R2 and R2' form together with R1 and R1' respectively, R22 and R22' form together with R21 and R21' respectively, R32 and R32' form together with R1 and R1' respectively, a 5 or 6 membered unsaturated or saturated carbocyclic ring optionally comprising 1 or 2 oxygen atoms, X is selected from the group consisting of hydrogen, fluoro, chloro, bromo, iodo, alkoxycarbonyl, aminocarbonyl, hydroxycarbonyl, a linear or branched C1 to C18 alkyl, a C1 to C18 alkenyl, a linear or branched C2 to C10 alkenyl, a sulfonate and OR50, wherein R50 is selected from the group consisting of hydrogen, a linear or branched C1 to C18 alkyl, and a linear or branched C1 to C9 alkylcarbonyl, and Y is selected from the group consisting of hydrogen, fluoro, chloro, bromo, iodo, a linear or branched C1 to C18 alkyl, a C1 to C18 alkenyl, a linear or branched C2 to C10 alkenyl, a sulfonate and OR50, wherein R50 is selected from the group consisting of hydrogen, a linear or branched C1 to C18 alkyl, and a linear or branched C1 to C9 alkylcarbonyl, R60 is selected from the group consisting of hydrogen, hydroxy and C1 to C18 alkoxy, and R61 is selected from the group consisting of hydrogen, hydroxy, C1 to C10 alkylsulfonyl-C1 to C5, and C1 to C18 alkyl as solvent, in particular as polar solvent, for chemical reactions, for recrystallizations or extractions.

2022

The importance/role of education in chemical engineering

Thierry Meyer

Chemical engineering as a skilled profession depends on the competencies of the individuals practicing it. Formal teaching of chemical engineering at universities only started in the 19th century. Informally, the subject has been in existence at least since Roman times. Highly skilled people have been recognised as a means to ensure prosperity and allow innovation for at least several centuries, as examples like the Bergakademie Freiberg show. It can be shown that skilled people flock to prosperous regions and prosperous regions develop where skilled people aggregate, modern examples include Silicon Valley and Northwestern Europe. The competences needed by a chemical engineer continue to broaden, e.g. sustainability, digitisation force changes in the education of engineers. The sheer volume of material cannot be covered in a tertiary study period and the speed of change makes knowledge obsolete very fast, which puts more focus on new life-long learning requirements. Modern, more individualised and context specific ways of education will develop, based sometimes on efficiency and cost of teaching and more often on effectiveness of learning.

2022

Sustainable polyesters via direct functionalization of lignocellulosic sugars

Adrien Julien Demongeot, Graham Reid Dick, Maxime Alexandre Clément Hedou, Harm-Anton Klok, Yves Leterrier, Jeremy Luterbacher, François Maréchal, Véronique Michaud, Thibault Rambert, Christèle Rayroud

The development of sustainable plastics from abundant renewable feedstocks has been limited by the complexity and efficiency of their production, as well as their lack of competitive material properties. Here we demonstrate the direct transformation of the hemicellulosic fraction of non-edible biomass into a tricyclic diester plastic precursor at 83% yield (95% from commercial xylose) during integrated plant fractionation with glyoxylic acid. Melt polycondensation of the resulting diester with a range of aliphatic diols led to amorphous polyesters (Mn = 30–60 kDa) with high glass transition temperatures (72–100 °C), tough mechanical properties (ultimate tensile strengths of 63–77 MPa, tensile moduli of 2,000–2,500 MPa and elongations at break of 50–80%) and strong gas barriers (oxygen transmission rates (100 µm) of 11–24 cc m−2 day−1 bar−1 and water vapour transmission rates (100 µm) of 25–36 g m−2 day−1) that could be processed by injection moulding, thermoforming, twin-screw extrusion and three-dimensional printing. Although standardized biodegradation studies still need to be performed, the inherently degradable nature of these materials facilitated their chemical recycling via methanolysis at 64 °C, and eventual depolymerization in room-temperature water.

2022

Green solvents for chemical reactions

Jeremy Luterbacher

2022