Research Output per year
Leon Lefferts (1960) was trained as a chemical engineer at the University of Twente (1983) and received his PhD in 1987 also at the University of Twente. He continued to specialize on heterogeneous catalysis and joined the DSM Research laboratories (1987-1999), working on catalyst characterization, hydrogenation, slurry phase catalysis, carbon supported metals and kinetics. He acted as research scientist, project leader as well as senior scientist.
He was appointed full professor “Catalytic Processes and Materials” (CPM) at the University of Twente in 1999. He has been visiting professor at Tokyo Institute of Technology, 2005-2007. He was appointed as Finnish Distinguished Professor in 2011-2015, and is continuing as a visiting professor at Aalto University in Helsinki till 2019.
The first theme is heterogeneous catalysts in liquid phase, motivated on both technological challenges, striving for minimization of concentration gradient in porous catalyst particles, as well as fundamental challenges, developing new experimental techniques for studying the catalyst surface in contact with liquid reactant mixtures and solutions. Most important results include the development of a new class of micro-structured catalyst supports (hairy foams) and more recently structured membrane contactor reactors based on CNFs, as well as pushing the borders of application of in-situ IR spectroscopy in aqueous phase with dedicated cells that enable Attenuated-Total-Reflection IR spectroscopy, recently even at elevated temperatures and pressures e.g. for aqueous phase reforming. The group is in the forefront of this technology and our work was highlighted in Chem. Soc. Rev.. Most of the work done so far was using hydrogenation of nitrate, nitrite and bromate as model reactions, that are also societal relevant in the realm of purification of drinking-water.
Second theme is activation of stable molecules, including selective oxidation. This work is exploring breakthrough technologies for activation of alkanes, e.g. via using soft oxidants, non-redox catalysts at high temperatures, electrical fields or plasma-catalysis. A cluster of three recent projects in close cooperation with DIFFER (FOM institute on energy, Prof. van de Sanden c.s.)) is aiming at combining plasma technology with heterogeneous catalysis, implying the need to build mutual understanding and cooperation with the plasma-physicists community. Joint workshops have been organized on this emerging theme, interacting with University of Antwerp (Prof. Bogaerts, dr. Meynen, TUe (Prof. Hessel) and in future also DIFFER will be involved. Furthermore, the use of water as a soft oxidant is of special interest and the role of oxide materials for activation of water is subject of investigations. The work on zirconia and ceria, both at Twente and at Aalto, is highly appreciated by the field, is frequently cited, and Leon delivered invited lectures on the subject. This work relevant is for steam reforming of hydrocarbons and oxygenates, as well as for water-gas-shift.
Finaly, catalytic upgrading of biomass, e.g. upgrading of flash-pyrolysis oil, both during flash-pyrolysis as well as down-stream has been an active research theme for quite some time. This direction was highly inspired on the early activities at University of Twente of prof. Wim van Swaaij, who explored the technology of flash pyrolysis at an early stage. The group has been a trendsetter in this field and early work on e.g. reforming of acetic-acid is an over-200 times cited research (non-review) paper. Also aqueous phase reforming of oxygenates and carbohydrates is studied in a number of projects. The most important result, next to a significant number of papers, is the development of a basic heterogeneous catalyst improving the quality of flash-pyrolysis oil, based on which KiOR decided to develop this technology to demonstration level.
Visiting Professor at Aalto University2011 → …
- QD Chemistry
- TP Chemical technology
- Heteroeneous Catalysis
- Liquid Phase
- Mass Transfer
- Plasma Catalysis
- Activation of stable molecules
Research output: Thesis › PhD Thesis - Research UT, graduation UT › Academic
Research output: Contribution to specialist publication › Article › Professional
Research output: Contribution to journal › Review article › Academic › peer-review
Research output: Contribution to journal › Article › Academic › peer-review
Activities per year
Activity: Talk or presentation › Oral presentation
Activity: Publication peer-review and editorial work › Editorial work
Activity: Talk or presentation › Invited talk