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Alkyl cyclohexanes were synthesized in high selectivity viaa combined hydrogenation/hydrodeoxygenation of aromatic ketones using ligand-free RhCl3as pre-catalyst in trifluoroethanol as solvent. The true catalyst consists of rhodium nanoparticles (Rh NPs), generated in situduring the reaction. A range of conjugated as well as non-conjugated aromatic ketones were directly hydrodeoxygenated to the corresponding saturated cyclohexane derivatives at relatively mild conditions. The solvent was found to be the determining factor to switch the selectivity of the ketone hydrogenation. Cyclohexyl alkyl-alcohols were the products using water as a solvent.

To date, a great number of various materials have been tested for the oxidative coupling of methane (OCM). On the basis of previous statistical analysis of OCM-related literature data, we developed novel catalysts based on K2MnO4or KMnO4supported on SiO2showing selectivity to C2-hydrocarbons (C2H4and C2H6) up to 68 or 66%. The analysis of catalysts containing the single components (Mn/SiO2, K2O/SiO2or SiO2) demonstrates that the co-existence of K and Mn is essential for achieving high selectivity to the desired products. The selectivity can be additionally improved when the OCM reaction is performed in the presence of water. The positive effect of water is attributed to the suppressed direct oxidation of CH4to CO2. Water also enhances the rates of methane conversion into C2-hydrocarbons and CO. Besides, the effects of water are more pronounced for samples based on crystalline SiO2rather than amorphous SiO2. Transient experiments with isotopically labelled oxygen suggest that the accelerating effect should be of heterogenous nature. As the positive influence of water on the selective methane oxidation to C2-hydrocarbons has been established over different catalysts, it may be advantageous to consider it when developing novel materials for the OCM reaction and even for other oxidation reactions.

A convenient methodology for perfluoroalkylation including trifluoromethylation of (hetero)arenes with perfluoroalkyl bromides was developed. Key for the success is the use of a specific cobalt-based nanocatalyst, which can be recycled at least up to 4 times. The scope of this first cobalt-catalyzed perfluoroalkylation is presented and detailed catalyst characterization (e.g.analytical STEM, XPS, and XRD) has been carried out.

Non-oxidative dehydrogenation of propane is one of the most promising technologies for propene production in terms of environmental impact and sustainability. The purpose of the present study was to develop environmentally friendly and low-cost alternatives to currently applied Pt- or CrOx-based catalysts. Rutile TiO2-based catalysts with supported ZnOxand ZrOxspecies were established to show promising performance under industrially relevant conditions. The amount of propene produced within 3 h on propane stream at 550 °C over the optimized catalyst with 2 wt% Zn and 5.6 wt% Zr is close to that obtained over commercial-like K–CrOx/Al2O3and the state-of-the-art Cu/YZrOxcatalyst. The selectivity to propene over our catalyst was about 95% at a propane conversion of about 23%. The kind of active sites and the effect of ZrO2addition on catalyst performance and physicochemical properties were elucidated owing to the application of complementary characterisation techniques such as XRD, N2physisorption, HRTEM, EDX, XPS, X-ray absorption spectroscopy, NH3-TPD, CO-TPR, Raman and O2-TPO. ZnOxclusters with 1–3 Zn atoms were concluded to be the active sites. ZrO2enhances their intrinsic activity and inhibits the formation of the inactive rhombohedral ZnTiO3phase.

Supported V2O5/Ce0.5Ti0.5−xMnxO2−δ(x= 0, 0.01, 0.05, 0.1, and 0.2) catalysts and bare supports were investigated in the selective catalytic reduction (SCR) of NO by NH3between 100 and 300 °C. Incorporation of Mn into Ce0.5Ti0.5O2increased the NO removal efficiency, reaching both NO and NH3conversions above 85% between 175 to 300 °C at remarkably high N2selectivities of ≥95%. Moreover, Mn-modified supports were also much more stable against deactivation in the presence of water. Deposition of vanadia on the Ce0.5Ti0.5−xMnxO2−δsupports enhanced the N2selectivity, reaching ≥98% in the whole temperature range for Mn percentages of ≤0.1. Characterization results revealed that incorporation of Mn leads to supports with higher lattice disorder and smaller crystallite size and enhances the oxygen mobility and the reducibility of the supports. OperandoEPR studies show that the synergistic effect of VOxand MnOxsurface species in moieties containing Mn3+/Mn2+and VO3+/VO2+in close vicinity contributes to the prevention of undesired NH3oxidation, thus improving the N2selectivity of these catalysts.