Now showing1 - 2 of 2
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Glycerol hydrogenolysis goes SMART - separating reaction steps as a key for tailoring selectivity and reaction control(American Chemical Society (ACS), 2026-05-27); ; ; ; The next generation of flexible, efficient, and robust chemical processes requires adaptive, resilient, and autonomous process systems that drive the transition from fossil to renewable feedstocks as one of the central challenges in building climate-neutral and sustainable chemical value chains. One central element will be the next generation of reactors that are SMART -Sustainable, Multipurpose, Autonomous, Resilient, and Transferable- merging process engineering with materials science, analytics, electronics, and data science. Herein, the chemical hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO) was used as a case study for tailoring selectivity and reaction control by coupling modeling with experimental approaches for process control, demonstrating adaptive reactor behavior. In detail, the reaction was split into a high-temperature step for the endothermic glycerol dehydration under an inert atmosphere and a consecutive low-temperature step under a hydrogen atmosphere, optimizing the reaction conditions for both reactions and deducing individual kinetic parameters by a graphical analysis of one-factor-at-a-time variations and a global nonlinear regression for the temporal concentration data. The results yield a reaction order of around 0.27 for glycerol with an activation energy of 43 kJ mol−1 for the dehydration step as well as reaction orders of zero for acetol and around 2.15 for hydrogen at an activation energy of 57 kJ mol−1 for the hydrogenation step. The simulated concentration profiles highlight the good agreement between the model and the experimental data. This allows for the implementation of the two-step reaction in a SMART reactor, strengthening the vision of a future generation of autonomous, resilient, and transferable process systems.Publicationtype: Journal Article58 52 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Boosting the chemical hydrogenolysis of glycerol to 1,2-propanediol to almost perfect selectivity using a multifunctional Ru–Cu carbon-nanotube-supported catalyst(American Chemical Society (ACS), 2026-04-03); ; ; Chemical hydrogenolysis of glycerol to propanediols is a promising strategy for biomass valorization. However, the demanding reaction conditions and deviating requirements for the individual reaction steps cause significant challenges to date. Herein, a kinetic study for the chemical hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO) as well as an optimized reaction procedure using a multifunctional Ru–Cu/CNT catalyst is presented. In detail, it was shown that the glycerol hydrogenolysis reaction is neither influenced by mass nor heat transfer limitations under the applied reaction conditions. Consequently, the following kinetic parameters could be deduced both by experimental determination as well as kinetic modeling: n (glycerol) = 1.1, n (H2) = 0.12 up to 25 bar (kinetic regime), and an activation energy of 150 kJ mol–1 for the desired 1,2-PDO pathway, as well as n (glycerol) = n (H2) = 0 for the undesired ethylene glycol pathway at an activation energy of around 65 kJ mol–1. Moreover, separating glycerol hydrogenolysis into two steps, initial glycerol dehydration to acetol under a nitrogen atmosphere at a high temperature of 220 °C, followed by acetol hydrogenation to 1,2-PDO under a hydrogen atmosphere at a low temperature of 145 °C using the same Ru–Cu/CNT catalyst, can lead to higher overall yields and almost perfect selectivity for 1,2-PDO. This could be verified in a separate experiment showing acetol selectivity of >99% for the first and 1,2-PDO selectivity of >99% for the second step without observable ethylene glycol production. Compared to the combined reaction under standard hydrogenolysis conditions of 50 bar H2 and 220 °C, almost perfect 1,2-PDO selectivity could be achieved, showing great potential for the separate approach. Moreover, a kinetic model of the glycerol hydrogenolysis based on the experimentally derived reaction rates confirms that the models reliably reproduce the observed reaction behavior with respect to the observed kinetic parameters.Publicationtype: Journal Article96 55