Group leader: C. Oliver Kappe
The Research Group - Flow Chemistry and Continuous Processing works on flow chemistry/microreaction technology, encompassing a wide variety of synthetic transformations and experimental techniques. Notably, these include handling hazardous, toxic and/or unstable reagents and gases in flow environments (e.g., H2, O3, O2, 1O2, H2O2, peroxides, CO, CO2, HN3, CH2N2, N2H4), many times in extreme temperature and pressure regimes reaching the near- or supercritical state. The group additionally has experience in flow photochemistry, nanoparticle and quantum dot synthesis in flow, and operating microwave-heated flow devices.
Green processes need to be scalable to have the greatest environmental impact, and ideally a direct translation from lab-to industrial scale would be desirable. Consequently, it is essential that safe, robust and cost effective processes are developed already in the earliest design stages by merging ideas stemming from both green chemistry and green engineering. Continuous flow processing specifically address these needs: For a large number of processes efficiency can be maximized – be it in mass, energy, space, and time – due to the enhanced heat and mass transfer, precise residence time control, shorter process times, better product quality, smaller footprint or easy scalability. Contributions from the Kappe group include the development of continuous processes for the preparation of a variety of chemicals, placing emphasis on sustainability and environmental footprint.
- COMET – K-Project CC FLOW
- An Integrated Flow Chemistry/Process Analytical Technology Platform (INFRA FLOW)
- Model-based Strategies for Realtime Control in Continuous API Manufacturing (SynthesisControl)
Group leader: Katalin Barta Weissert
Research in the Barta group is centered around sustainability and Green Chemistry with a special focus on the conversion of renewable resources and catalysis using earth-abundant metals. Two main research lines are being pursued:
1.) Synthesis and characterization of novel heterogeneous catalysis for the cleavage of crude lignocellulose resources, including lignocellulose pre-treatment and characterization
2.) New homogeneous catalytic methods for the atom-economic functionalization of the obtained building blocks.
A variety of research lines include reductive and hydrogen-neutral depolymerisation and defunctionalization of lignin to aromatic monomers. Similarly, reductive approaches using copper catalysts are used for the conversion of cellulose and derived platform chemicals to a variety of end products. Here, the central aim is to find new concepts that allow to deal with complexity and changed material inputs and to identify causes of and minimize side reactions which lead to decreased product yields. In addition, we are involved in developing new methods for iron-catalysed coupling of alcohols and amines as well as hydrogenation of carbonyl compounds including esters also in an asymmetric fashion.
Selection of research projects
Lignin to aromatic monomers : One core expertise is the depolymerisation and defunctionalization of lignin to aromatic monomers using simple acid catalyzed methods that can be relevant in future biorefinery approaches. Here we are particularly interested in the identification and in situ stabilization of reactive intermediates obtained after lignin acidolysis.
Lignin depolymerization using CuPMO catalysts: Here, for selective bond cleavage reactions copper based catalysts are used. At milder reaction temperatures, aromatic monomers are obtained. Model compounds and real lignin feeds are also used. These catalysts can be also used together in supercritical fluids, such as scMeOH, in which case the in situ formed hydrogen is responsible for the bond cleavage
Methanol can also act as carbon source for example for the construction of benzimidazole derivatives. The reaction takes place using simple aromatic diamines in supercritical methanol, using CuPMO.
The conversion of sugar derived platform chemicals, such as HMF: 5-hydroxymethyl furfural is one of the central sugar derived platform chemicals. Its selective and high yield conversion to diols that can serve as monomers for the polymer industry or to fuel additives such as 2,5-dimethylfuran is still a challenge. We have found that for example CuZn alloy nanopowder is a very efficient catalyst for this purpose.
Iron-catalysis: The direct functionalization of alcohols with simpler amines to form more functionalized amines is an important reaction for the valorization of biomass derived, highly oxygenated substrates. We are interested in using methodologies that are based on well-defined Fe complexes, and that are atom efficient and only produce water as byproduct.
Harald StelzerResearch Manager
Research Management & -services
A- 8010 Graz
Wegener Center for Climate and Global Change
Institute of Philosophy
Institut für Volkswirtschaftslehre
Institut für Biologie