Final Report Summary - KINPOR (First principle chemical kinetics in nanoporous materials)
The principle aim of the ERC KINPOR project was the development and applications of theoretical methods for the determination of first principle chemical kinetics in nanoporous materials, i.e. without any experimental input. Applications have been performed in two types of materials : (i) zeotype materials, both alumino-silicates and alumino-phosphates with various topologies that have industrial relevance (ii) metal organic frameworks, a class of crystalline porous materials composed of organic and inorganic moieties. All applications are performed in close collaboration with experimental partners at the national and international level.
Whereas in the past the focus was often set on qualitative insight of chemical transformation and reaction cycles, today with current theoretical models, also chemical accurate rate constants have now become within reach. Within the framework of the ERC funded research, we showed that absolute reaction rates for reactions occurring over acidic zeolites can be calculated with near chemical accuracy, i.e. having a deviation of less than a factor 10 compared to experimentally determined data. (V. Van Speybroeck et al., Journal of the American Chemical Society 2011, 133, 888.) The proposed scheme is computationally very efficient and constitutes significant progress in kinetic modeling of reactions in heterogeneous catalysis. The new set of methods were used to study the effects of topology on the industrial relevant methanol to olefin process (MTO), one of the most prominent technologies in petrochemical industry to bypass crude oil as a fundamental feedstock which is very significant in view of the waning oil reserves. Together with the experimental research group of Prof. Olsbye (University of Oslo, Norway) we succeeded in explaining the topology effects of some important zeolites on the methylation of aromatics. (J. Van der Mynsbrugge et al. Journal of Catalysis 2012, 292, 201.) Furthermore theoretical models were developed to study alumino-phosphates, which constitute an important class of materials for industrial applications (SAPO-34,…). Within the framework of this project, we studied the influence of additional solvent molecules which are trapped in the porous material by means of molecular dynamics methods. It was concluded that a simple view of a localized Brønsted acid site at which the reaction occurs is far too simplistic for some reactions at realistic conditions. The approach was also used to study the effect of guest molecules on the occurrence of competitive pathways within the Methanol to Olefin process. All our insights led to a review on reaction mechanisms relevant for the MTO process, with special focus on the interplay between theory and experiment [K. Hemelsoet et al. , Chemphyschem, 2013, 14, 1526-1545..] Very recently I published a review on invitation for Chemical Society Reviews which gives a current status of the field for calculating chemical kinetics using first principle methods including all my major achievements resulting from KINPOR [V. Van Speybroeck, K. De Wispelaere, J. Van der Mynsbrugge, M. Vandichel, K. Hemelsoet and M. Waroquier, Chem. Soc. Rev., 2014, 43, 7326-7357].
The second application window of the ERC KINPOR focuses on Metal-Organic Frameworks (MOFs) which are much more flexible than zeotype materials and exhibit typical breathing phenomena which are triggered by external stimuli such as the presence of guest molecules. This flexibility may have a serious impact on the catalytic properties of these materials. A theoretical framework was developed to derive force fields for flexible materials from first principle (L. V. Vanduyfhuys, et al., Journal of Computational Chemistry, 2015, in press.). The newly developed force fields were successfully used to study the breathing behaviour, the thermodynamics and pressure induced breathing of MIL-53 type materials. The theoretical methods were successfully applied on a variety of MOFs to unravel the nature of the active sites. This was done to study the oxidation of cyclohexene over vanadium based MOFs in collaboration with the experimental group of Prof. Van der Voort (UGent).
Together with the Catalysis group of D. De Vos (KULeuven) we studied various Lewis based catalysed reactions. We showed that the catalytic activity of the UiO-66(Zr) material could be substantially improved by a modulation approach. Our theoretical group contributed to the insight that intentional creation of defects is a corner stone for catalysis in MOFs and calculated the free energies of defect formation in MOFs (M. Vandichel, et al. , CrystEngComm, 2015, 17, 395-406.)
All software developed within the framework of the program is freely available under the open source modalities via http://molmod.ugent.be/software.
Whereas in the past the focus was often set on qualitative insight of chemical transformation and reaction cycles, today with current theoretical models, also chemical accurate rate constants have now become within reach. Within the framework of the ERC funded research, we showed that absolute reaction rates for reactions occurring over acidic zeolites can be calculated with near chemical accuracy, i.e. having a deviation of less than a factor 10 compared to experimentally determined data. (V. Van Speybroeck et al., Journal of the American Chemical Society 2011, 133, 888.) The proposed scheme is computationally very efficient and constitutes significant progress in kinetic modeling of reactions in heterogeneous catalysis. The new set of methods were used to study the effects of topology on the industrial relevant methanol to olefin process (MTO), one of the most prominent technologies in petrochemical industry to bypass crude oil as a fundamental feedstock which is very significant in view of the waning oil reserves. Together with the experimental research group of Prof. Olsbye (University of Oslo, Norway) we succeeded in explaining the topology effects of some important zeolites on the methylation of aromatics. (J. Van der Mynsbrugge et al. Journal of Catalysis 2012, 292, 201.) Furthermore theoretical models were developed to study alumino-phosphates, which constitute an important class of materials for industrial applications (SAPO-34,…). Within the framework of this project, we studied the influence of additional solvent molecules which are trapped in the porous material by means of molecular dynamics methods. It was concluded that a simple view of a localized Brønsted acid site at which the reaction occurs is far too simplistic for some reactions at realistic conditions. The approach was also used to study the effect of guest molecules on the occurrence of competitive pathways within the Methanol to Olefin process. All our insights led to a review on reaction mechanisms relevant for the MTO process, with special focus on the interplay between theory and experiment [K. Hemelsoet et al. , Chemphyschem, 2013, 14, 1526-1545..] Very recently I published a review on invitation for Chemical Society Reviews which gives a current status of the field for calculating chemical kinetics using first principle methods including all my major achievements resulting from KINPOR [V. Van Speybroeck, K. De Wispelaere, J. Van der Mynsbrugge, M. Vandichel, K. Hemelsoet and M. Waroquier, Chem. Soc. Rev., 2014, 43, 7326-7357].
The second application window of the ERC KINPOR focuses on Metal-Organic Frameworks (MOFs) which are much more flexible than zeotype materials and exhibit typical breathing phenomena which are triggered by external stimuli such as the presence of guest molecules. This flexibility may have a serious impact on the catalytic properties of these materials. A theoretical framework was developed to derive force fields for flexible materials from first principle (L. V. Vanduyfhuys, et al., Journal of Computational Chemistry, 2015, in press.). The newly developed force fields were successfully used to study the breathing behaviour, the thermodynamics and pressure induced breathing of MIL-53 type materials. The theoretical methods were successfully applied on a variety of MOFs to unravel the nature of the active sites. This was done to study the oxidation of cyclohexene over vanadium based MOFs in collaboration with the experimental group of Prof. Van der Voort (UGent).
Together with the Catalysis group of D. De Vos (KULeuven) we studied various Lewis based catalysed reactions. We showed that the catalytic activity of the UiO-66(Zr) material could be substantially improved by a modulation approach. Our theoretical group contributed to the insight that intentional creation of defects is a corner stone for catalysis in MOFs and calculated the free energies of defect formation in MOFs (M. Vandichel, et al. , CrystEngComm, 2015, 17, 395-406.)
All software developed within the framework of the program is freely available under the open source modalities via http://molmod.ugent.be/software.