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Das Institut fur Heise Chemie IHCh wurde 1959 gegrundet, um die Entwicklung der Technologie zur Wiederaufarbeitung von Kernbrennstoffen zu unterstutzen. Aufbauend auf dem sog. PUREX-Prozess wurden mogliche Varianten zur Abtrennung von noch nutzbarem Spaltmaterial durch Kombination verschiedenster Extraktions- und Redoxverfahren vom Labor- bis zum Pilotmasstab entwickelt, bis dieser mit nur noch einem Extraktionszyklus auskam. Mit dem Ende der nuklearen Reaktorforschung wurden als Institut fur Technische Chemie neue Themen aus der Umwelt- und Energieforschung aufgegriffen. In dieser Zeit wurde im Rahmen der internationalen Kollaboration GALLEX ein radiochemischer Sonnenneutrino-Detektor gebaut und erfolgreich betrieben.

Die Methodik EDUAR&D, kurz für Energiedaten und -analyse R&D, wird zur Bewertung von Energieeffizienztechniken genutzt. Es handelt sich um einen strukturierten Such- und Analyseprozess, der verschiedene methodische Ansätze zur Darstellung, Analyse und Bewertung der Techniken miteinander verbindet. Ziel ist es, Handlungsempfehlungen, z. B. bzgl. thematischer Schwerpunktsetzung, für die zukünftige Energieforschung im Rahmen der Forschungsförderung und für die Energiepolitik abzuleiten. Die Methodik wird hier am Beispiel der organophilen Nanofiltration und der Latentwärmespeicher vorgestellt.

Oligomeric oxymethylene dimethyl ethers (OMEn, CH3(OCH2)nOCH3, n = 1 – 5) are promising diesel fuels for the reduction of harmful emissions. If OMEs are produced from dimethoxymethane and trioxane, the resulting OME mixtures usually contain residual trioxane which appears, after rectification, in the OME2 fraction. To circumvent this obstacle, substoichiometric amounts of trioxane have been employed in OME synthesis. Thus, OME2 samples with high purity could be prepared. Physicochemical and fuel data of high purity OME2 and higher OMEs have been determined to supplement previously reported data.

Modeling of fast pyrolysis reactors is challenging, even with state of the art computational tools and design, because rules to scale up well-running fast pyrolysis reactors are missing. Dimensional analysis is a classical tool to evaluate complex processes on a scientific basis and its application to fast pyrolysis is presented herein. Using the example of auger-type fast pyrolysis reactors, it is shown that scale-up can be reduced to a set of simple design rules. Full similarity of reaction conditions can never be achieved for fast pyrolysis in general, but it is shown which similarities are affected and to which extent they change. Dimensionless numbers derived from this analysis can even be used to describe the influence of parameters on the reactor performance; however, a significant reduction in complexity is required to achieve a practical relevance list. Strategies are outlined to achieve such a reduction based on partial similarities of rate-determining steps.

The single‐step syngas‐to‐dimethyl ether (STD) process entails economic and technical advantages over the current industrial two‐step process. Pd/ZnO‐based catalysts have recently emerged as interesting alternatives to currently used Cu/ZnO/Al2O3 catalysts, but the nature of the active site(s), the reaction mechanism, and the role of Pd and ZnO in the solid catalyst are not well established. Now, Zn‐stabilized Pd colloids with a size of 2 nm served as the key building blocks for the methanol active component in bifunctional Pd/ZnO‐γ‐Al2O3 catalysts. The catalysts were characterized by combining high‐pressure operando X‐ray absorption spectroscopy and DFT calculations. The enhanced stability, longevity, and high dimethyl ether selectivity observed makes Pd/ZnO‐γ‐Al2O3 an effective alternative system for the STD process compared to Cu/ZnO/γ‐Al2O3., Zinc‐stabilized palladium colloids with a size of about 2 nm are the key building units for bifunctional syngas‐to‐dimethyl ether catalysts with enhanced stability, longevity, and high dimethyl ether selectivity. The catalysts were characterized by combining high‐pressure operando X‐ray absorption spectroscopy and DFT calculations.

The gasification of microalgae in supercritical water was investigated in this work. The product gas contained mainly H2, CO2, CH4, and C2H6. Operation at high temperatures and lower biomass concentrations resulted in the highest carbon gasification efficiency and the lowest total organic carbon levels in the residual water. Due to its content of inorganic nutrients, the residual water was applied as cultivation medium for microalgae. However, algal growth in the untreated residual water was inhibited by the existence of potentially toxic substances evolved from gasification. Upon treatment by activated carbon filtration and ultraviolet light degradation, these substances were eliminated and cultivation in the residual water was possible. The major fraction of inorganic residues from gasification was recovered by means of water purging, increasing the potential of nutrient recycling for cultivation.

The demand, production, supply and use of biomass in a future world after the depletion of fossil fuels is described. In a world without fossils, the limited biomass harvest is the only carbon source. Supply of food and feed has first priority. Demand, supply and use of biomass as the only carbon raw material for the production of a number of indispensable carbon products are analyzed. Bioenergy via combustion plays a significant, but not a decisive role, because the future energy mix is dominated by other renewables. Despite considerable uncertainties of the long-term assessment, some clear hints for a reasonable further development of biomass technologies can be extracted.

Catalysts of the type Cu/Co/ZnO/SiO2 were prepared by impregnation, subsequent calcination and reduction with hydrogen. Characterization of the catalysts was carried out by ICP-AES, BET measurements and powder X-ray diffraction analyses. Furthermore, temperature programmed reduction was employed to investigate their reduction behavior. The catalysts were tested in the conversion of synthesis gas to hydrocarbons and alcohols. High CO conversions could be reached in a single reactor pass. Selectivity was highest for methane, and short-chain hydrocarbons, but alcohols were also formed.

Kokspartikel aus pyrolysierter Biomasse variieren stark in Partikelgrose und -form. Die durchschnittliche Langlichkeit der Partikel nimmt mit der Grose signifikant zu. In Abhangigkeit der Partikelgrose ist die durchschnittliche Langlichkeit fur die untersuchten Proben unabhangig von Ausgangsstoff und Pyrolyseverfahren. Mit klassischen kugelbasierten Grosenverteilungen werden die Partikel nur ungenau beschrieben. Unter Berucksichtigung der Partikelform lassen sich die Kokse mittels Partikelgrosenverteilungen beschreiben, die auf einem Ellipsoidmodell basieren. Die hohe Schuttgutporositat ist im Wesentlichen auf die interpartikularen Zwischenraume zuruckzufuhren. Char particles from pyrolyzed biomass vary in particle size and shape. On average, the particles are more elongated the larger their size. The average size-specific elongation is almost alike for all investigated samples, i.e. independent from their source material and process. The particle collectives cannot be characterized accurately with classical particle size distributions, which assume spherical particle shape. Accounting for their shape, they can be described more accurately with particle size distributions that are based on an ellipsoid model. The high bulk porosity is mainly attributed to the spaces between particles.

Der Flachendeckende Einsatz des Lasers in der Produktion sorgt fur neue Moglichkeiten, hochste Qualitat bei geringen Kosten zu erreichen. In diesem Beitrag wird anhand eines Beispiels aus der Medizintechnik ein anderer Einsatzfall der Lasertechnologie vorgestellt: die 100% Qualitatskontrolle der Eigenschaften des Herzstucks eines Inhalationssystems zur optimierten Therapie von Atemwegserkrankungen.

An experimental investigation in a tube wall reactor with catalyst-coated inner wall is presented. Yields of formaldehyde of more than 70% can be obtained in the selective methanol dehydrogenation over alkalialuminate. Models for the reactor and the system of most important homogeneous reactions are derived. Different models describing the catalytic action are proposed. The results can only be explained by a new type of catalytic reaction, not described so far in the literature. Reducing gases like hydrogen and methanol lead to a volatilization of material from alkalialuminate which apparently catalyzes the dehydrogenation in the gas phase. Calculations and experimental evidence lead to the conclusion that this material should be sodium atoms. These are engaged in the homogeneous radical chain reaction by regulating the concentration of hydrogen atoms.