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Item type:Publication, Access status: with files , Investigations on the role of support and synthesis procedure for the Rux–Cuy/CNT‐catalysed hydrogenolysis of glycerol to 1,2‐propanediol(Wiley, 2026-07-14); ; ; Tailoring support effects plays an important role for controlling activity and selectivity in heterogeneously catalyzed gas–liquid reactions. Sophisticated carbon supports like single‐ and multiwall carbon nanotubes (CNTs) as well as in house produced Globugraphite were used for the synthesis of bimetallic Ru–Cu catalysts, which were tested in a multibatch reactor setup for the chemical hydrogenolysis of glycerol to 1,2‐propanediol (1,2‐PDO) in aqueous solution. In‐depth characterization using multiple tools like inductively coupled plasma optical emission spectrometry, CHNS‐O analysis, N₂‐physisorption, scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, powder X‐ray diffraction, H₂‐temperature programmed reduction, laser diffraction, and point of zero charge measurements revealed the dominating effects that the various carbon supports exert on the catalytic performance. The best‐performing catalyst synthesized by wetness impregnation consisted of Ru–Cu₃ nanoparticles (NPs) from mixed RuCl₃ and Cu(NO₃)₂ precursors dispersed on multiwall CNT Baytubes with a productivity of p = 12.74 g₁,₂‐PDO gactive metal ⁻¹ h⁻¹ . Its superior activity combined with high 1,2‐PDO selectivity (S= 75%) can be explained both by the nature of the highly dispersed Ru and Cu NPs showing the lowest reduction peak temperature on entangled tubes of CNT agglomerates demonstrating a high mesopore volume for optimal reactant accessibility and the highest specific surface area of all investigated materials. This lays the foundation for implementing this highly active and selective catalyst in a future SMART reactor for glycerol valorisation.Publicationtype: Journal Article57 40 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Multifunctional carbon‐nanotube supported catalyst for efficient glycerol hydrogenolysis to 1,2‐propanediol(Wiley, 2026-03); ; Multiwall carbon nanotube (NC7000) supported mono-, bi-, and trimetallic catalysts were synthesized and tested in a multi- batch reactor setup supported by data-driven modeling for the chemical hydrogenolysis of glycerol to 1,2-Propanediol (1,2-PDO) at 220◦C under 30 bar hydrogen pressure in aqueous solution. ICP-OES, N2 -physisorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDX), powder x-ray diffraction (XRD) and x-ray photoelectron spectroscopy (XPS) were used to investigate the physico-chemical properties of the synthesized catalysts. Interesting structure-activity-selectivity correlations could be deduced from the different metal ratios and combinations. While Ru was by far the most active monometallic species ( X = 100%), followed by Pt ( X = 80%) and Ir ( X = 65%), it suffered from a very low 1,2-PDO selectivity ( S < 10%). Combining Ru with the more selective transition-metals RuX2 ( X = Fe, Co, or Ni) maintained the high activity ( X > 95%) but only moderately increased 1,2-PDO selectivity ( S = 20%–30%). Interestingly, combining Ru with Cu in a bimetallic RuCu2 catalyst slightly decreased activity ( X = 81%) but drastically improved 1,2-PDO selectivity ( S = 58%). Moreover, a trimetallic combination of RuMCu2 (M = Pt, Pd, Ir) did not further increase activity ( X = 50%–70%) but could push 1,2-PDO selectivity up to 79% for the trimetallic RuIrCu2 catalyst. Most prominently, a final metal ratio variation for the RuCux catalyst was derived with the help of the data-driven models producing the most promising RuCu3 /NC7000) catalyst combining both high activity ( X = 78%) with a very high 1,2-PDO selectivity ( S = 79%) resulting in the highest 1,2-PDO yield of 58% in a nearly closed carbon balance ( C > 95%). This lays the foundation for implementing this highly active and selective catalyst in a future SMART reactor for glycerol valorization.Publicationtype: Journal Article87 78 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Spatially resolved reaction profiles of CO2 hydrogenation to methanol using in-based catalysts in a compact profile reactor(American Chemical Society (ACS), 2024-06-07); ; ; ; The compact profile reactor (CPR) design allows for the simultaneous acquisition of species, temperature, and spatially resolved reaction profiles during high-pressure CO2 hydrogenation to methanol. Indium-based catalysts for CO2 hydrogenation have attracted significant scientific interest since they are more selective, efficient, and resistant to deactivation compared to the state-of-the-art copper-based catalyst. In this study, the reaction profile of In2O3/ZrO2 catalysts is compared to that of the state-of-the-art Cu/ZnO/Al2O3 (CZA) catalyst in a high-pressure CPR. It is demonstrated that the addition of nickel as a promoter significantly enhanced the catalytic activity of pure In2O3/ZrO2. The characterization by H2 TPR and CO2 TPD revealed an increased capacity for both hydrogen and CO2. A detailed comparison and optimization of reaction conditions using Ni–In2O3/ZrO2 as a catalyst are presented. In an optimized experiment, Ni–In2O3/ZrO2 produces 4.90 gMeOH gIn+Ni–1 h–1 at 275 °C, 50 bar, and 63,000 h–1with a methanol selectivity of 73%. Furthermore, no catalyst deactivation caused by metal leaching or sintering could be observed over 90 h time on stream.Publicationtype: Journal Article212 127