The gas-phase loading of [Zn(4)O(btb)(2)](8) (MOF-177; H(3)btb=1,3,5-benzenetribenzoic acid) with the volatile platinum precursor [Me(3)PtCp'] (Cp'=methylcyclopentadienyl) was confirmed by solid state (13)C magic angle spinning (MAS)-NMR spectroscopy. Subsequent reduction of the inclusion compound [Me(3)PtCp'](4)@MOF-177 by hydrogen at 100 bar and 100 degrees C for 24 h was carried out and gave rise to the formation of platinum nanoparticles in a size regime of 2-5 nm embedded in the unchanged MOF-177 host lattice as confirmed by transmission electron microscopy (TEM) micrographs and powder X-ray diffraction (PXRD). The room-temperature hydrogen adsorption of Pt@MOF-177 has been followed in a gravimetric fashion (magnetic suspension balance) and shows almost 2.5 wt % in the first cycle, but is decreased down to 0.5 wt % in consecutive cycles. The catalytic activity of Pt@MOF-177 towards the solvent- and base-free room temperature oxidation of alcohols in air has been tested and shows Pt@MOF-177 to be an efficient catalyst in the oxidation of alcohols.

The vapour pressure and the thermal stability of liquids are important material properties. For high boiling organic and ionic liquids (ILs), the determination of these properties is laborious and it is not easy to discriminate between evaporation and thermal decomposition. In this work, a simple but accurate method is presented to determine the parameters of decomposition and evaporation by thermogravimetrical analysis (TGA). The mass transfer coefficient was calculated based on a new correlation for the Sherwood number for cylindrical crucibles in overflow of a carrier gas. This correlation is valid for any diameter-to-height ratio and for any filling degree of the crucible and was derived from numerical simulations and proven by experiments with hexadecane, dodecane, and anthracene. The TGA analysis of two ILs was conducted. [EMIM][EtSO(4)] decomposes at ambient pressure without a measurable contribution of evaporation. To the contrary, [BMIM][NTf(2)] is relatively volatile. The vapour pressure of [BMIM][NTf(2)] and the kinetics of decomposition of both ILs were determined.

Ionic liquids (ILs) are widely discussed as alternative green solvents not only because of their unique chemical properties, but also because of their extremely low vapour pressure and -at least in some cases -relatively high thermal stability. Two complementary methods are analyzed and compared to determine both the rate constant of decomposition and the vapour pressure of four ILs: (1) thermogravimetrical analysis at ambient pressure (TG ap ) with an overflow of inert gases, and (2)

The substitution of fossil fuels by renewable energy sources is needed to decrease greenhouse gas emissions, especially CO2. Wind and solar power are today considered as attractive alternatives for electric power generation, but are not suitable for providing base load. Thus, efficient storage of electrical energy is inevitable. Liquid hydrocarbons (HCs) exhibit an excellent volumetric energy density and offer various opportunities for storing electric energy. They can be produced by CO2 and renewable H2 (generated by water electrolysis) in a two step process. The first step is generation of syngas by reverse water‐gas shift (RWGS) at elevated temperatures; the second step comprises the production of liquid hydrocarbons by Fischer‐Tropsch (FT) synthesis. The experiments on RWGS with a commercial Ni‐catalyst show that a CO2 conversion of around 80 % can be reached at 800 °C within a very short residence time of less than < 0.1 s. The experiments on FTS with Fe as catalyst and syngas containing different amounts of CO2 indicate that the influence of CO2 on CO conversion and product selectivities (including net CO2 production by water‐gas shift) is insignificant if the inlet partial pressures of H2 and CO are kept constant. If CO is substituted by CO2, less HCs are formed, the water‐gas shift is repressed, and methane selectivity increases.

The results of the simulation of multi-tubular Fischer-Tropsch reactors based on a two-dimensional pseudo-homogeneous model are presented. The model takes into account the intrinsic kinetics of two commercial iron and cobalt catalysts, intraparticle mass transfer limitations, and the radial heat transfer within the fixed bed and to the cooling medium (boiling water). The effective rate with Co is slightly higher than with Fe. Hence, a temperature level can be used for Co that is 20°C lower compared to Fe. The conversion and product selectivies are then almost the same and the reactor can be operated safely without a temperature runaway. The results of the simulations are consistent with literature data and show that there is still room for improvement of fixed bed FT reactors, e.g., by an enhanced heat transfer.

The synthesis of liquid fuels from CO 2 , e.g., separated from flue gases of power plants, and H 2 from renewables, i.e., water electrolysis, is a concept for substituting fossil fuels in the transport sector. It consists of two steps, syngas production via reverse water-gas shift (RWGS) and synfuel production by Fischer-Tropsch synthesis. Research is concentrated on the RWGS using a Ni-catalyst. The catalyst shows an appropriate performance in catalyzing the RWGS. The catalyst is stable at technically relevant temperatures. The intrinsic and effective kinetics were determined and considerations on a technical application of the process are proposed.

Ionic liquids (ILs) are widely discussed as alternative, sustainable solvents not only because of their unique chemical properties, but also because of their extremely low vapor pressure and – at least in some cases – relatively high thermal stability. In this work the vapor pressure data and kinetics of decomposition are presented for some selected pure and supported ionic liquids. Based on these results general strategies to determine the volatility and stability of pure and supported ILs as well as criteria for the maximum operation temperature with regard to decomposition and evaporation are introduced.

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