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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.

Heterogeneous catalysis and anaerobic syngas fermentation represent two different approaches for the conversion of synthesis gas into chemicals and fuels. This review provides a unique comparison of different reaction paths for the fixation of CO$_{2}$, CO and H$_{2}$ into elementary building blocks such as methanol, acetic acid and ethanol. Operating conditions, reactor engineering, influence of gas impurities, yields, conversion efficiencies as well as downstream product recovery are compared. It was found that mass-specific productivity ranges in the same order of magnitude for both technologies, while space-time yield of heterogeneous catalysis is up to three orders of magnitude higher.

PtX technologies are one major building block of the future energy system based on renewables sources. Dimethyl ether (DME) is an important PtX product that can be used as intermediate the production of CO$_{2}$-neutral base chemicals. New applications lead to an increase of the global production and the optimization of the process efficiency, especially when considering decentralized synthesis. This review article puts some spotlights on recent developments in methanol and the direct DME synthesis with a special focus on the modeling and bifunctional catalyst. This study is expected to provide a foundation for future works in the field of catalysis research based on catalysts design and kinetic modeling.

The environmental impact of the increasing anthropogenic CO2 emissions and the depletion of essential resources, once subjects of concern only for a minority of specialists, are now in the focus of many institutions and are de facto top priorities in many agendas. The ensuing environmental regulations, improved safety requirements, and growing critical public view on the chemical industry are the main reasons for an intense search for alternative synthetic routes to commodity chemicals and specialty chemicals. The skillful utilization of waste biomass, an inexhaustible resource, is revealed to be an important tool for a balanced CO2 management and the way to promising feedstock for many chemical and biochemical syntheses. The scope of the present contribution is to outline the main differences between chemical and biotechnological synthesis routes starting from waste biomass, focusing on C4-chemicals as an exemplary case study.

Hierarchical H-ZSM-5 zeolites are a promising class of heterogeneous catalysts that have shown encouraging results in lab-scale studies for the production of gasoline from dimethyl ether (DTG conversion). However, the influences of mesopore formation and shaping on various catalyst properties are still under debate. In this study, a series of H-ZSM-5 zeolites with hierarchical pore structures were prepared by modifying commercially available zeolites via alkaline treatment ("desilication"). The powdered zeolites were shaped into technical catalyst bodies by wet extrusion using either silica or alumina binders. All materials were extensively characterized. The different interactions during alkaline treatment were related to the observed modifications in the zeolite properties of the materials obtained. Although many properties of modified and untreated zeolite powders remained predominantly unchanged in their shaped catalyst equivalents, both binders affected certain material characteristics, particularly those related to their acidity. Finally, preliminary tests showed enhanced catalytic performance of hierarchical ZSM-5 catalysts in DTG conversion.

Oligomeric oxymethylene dimethyl ethers (OMEs) of the type CH3O-(CH2O)n-CH3 are promising diesel fuels with an enormous potential for the reduction of soot and NOx emissions. Oligomers with n = 3–5 are particularly advantageous, since their physicochemical and combustion properties are similar to conventional diesel. OMEs can be produced from methanol and formaldehyde but a series of byproducts, especially hemiformals, glycols, water and minor amounts of cyclic ethers, are also formed. These need to be separated from the product mixtures, which affects efficiency of this synthesis pathway. To isolate the desired OMEs, a one-step synthesis/extraction procedure is described. It implies highly selective extraction of OMEs from aqueous reaction solutions employing hydrocarbons as extraction agents. If fuel-type hydrocarbons are used, the resulting OME-hydrocarbon blends can be directly used in fuel applications. The corresponding oxymethylene diethyl ethers (OMDEEs) have also been investigated. Compared to OMEs, OMDEEs exhibit an increased solubility in nonpolar media but, as a result, solubility of educts and byproducts also increases. OME blends with hydrogenated vegetable oil and diesel have been prepared containing 10% of OMEs. It could be shown that such blends meet current diesel standards to a large extent.

Oligomeric oxymethylene dimethyl ethers (OME n , CH 3 O(CH 2 O) n CH 3 ) bearing three to five CH 2 O units are promising diesel fuels for the reduction of soot and NO x emissions. Regarding the production of OMEs, a highly optimized process has not been realized yet. This work describes efficient synthesis of OMEs from dimethoxymethane (DMM) and trioxane in batch experiments at room temperature and atmospheric pressure. To ensure high reactivity and high OME yields, dry educts have been used and the influence of water has been investigated in detail. The ion exchange resin Amberlyst36 and zeolites have been employed as acidic catalysts. Zeolite BEA25 exhibited highest catalytic activity and the reaction could be completed within 12 min at 25 °C. Furthermore, the formation of byproducts could be fully eliminated.

A catalyst screening comprising zeolites and ion exchange resins for the synthesis of oligomeric oxymethylene dimethyl ethers (OME) from methanol (MeOH) and formaldehyde (FA) has been carried out. All catalysts led to the same product spectrum and parameters for chemical equilibrium have been determined. The ion exchange resin Dowex50Wx2 showed highest activity and reaction kinetics has been investigated employing this catalyst. The influence of the FA:MeOH ratio and water as well as refeeding of OMEs with undesired chain lengths have been considered in the kinetic model, which is based on a hyperbolic approach. Experiments have been carried out in the temperature range between 40 and 120 °C and variable FA:MeOH ratios from 0.5 to 1.5 g/g have been employed. Regarding water, up to 23 wt.% have been added to the reaction mixtures to investigate its influence on yield and reaction rate. Low water contents lead to high OME selectivities. By varying the FA:MeOH ratio, chain lengths of the OMEs can be influenced. Regarding the most active catalyst Dowex50Wx2, 90% of equilibrium conversion is reached after 5 min at 60 °C employing a catalyst loading of 1 wt.%. A study on the long term performance of the catalyst has been carried out and after 17 days the decrease of activity was below 10% while selectivity remained the same. For different Dowex catalysts a general kinetic model could be developed, which is not limited to Dowex50Wx2.

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.

Aktuelle Trends aus der chemischen Prozesstechnik im Rahmen der Begleitforschung des Forschungsnetzwerkes Energie in Industrie und Gewerbe (EE4InG) werden vorgestellt. Wir gehen davon aus, dass die Trends zirkulare Wirtschaft und beschleunigte globalisierte Innovation (Modularisierung, Prozessintensivierung und Digitalisierung) bis 2030 auf die Chemieindustrie wirken. Die Technologieentwicklung anhand dieser Trends erlaubt es dem Chemieingenieurswesen, zukunftig entscheidende Beitrage zur Flexibilisierung und Defossilisierung der Wertschopfungsketten zu leisten.

Within the so-called bioliq® process, renewable carbon resources, especially agricultural residues, are converted to gasoline. The process chain comprises pyrolysis of the feedstocks, gasification to synthesis gas, gas cleaning and conversion of synthesis gas to dimethyl ether (DME) followed by conversion of DME to hydrocarbons. Construction of all process units has been completed now and the entire plant has been successfully operated in several campaigns. Thus, hundreds of liters of a new alternative gasoline are available now, which allow for an extensive testing. The basic characteristics of the resulting bioliq®/100 fuel are described. It is rich in aromatics and a blend consisting of 90 Vol.−% of conventional RON95 E5 fuel and 10 Vol.−% of bioliq®/100, designated as bioliq®/10, has been produced which meets the DIN EN 228 standard. Initial measurements on a single cylinder research engine have been carried out focusing on efficiency and emissions. A comparison of bioliq®/10 with neat RON95 E5 revealed an improved knocking behavior of bioliq®/10 even by a small fraction of regenerative bioliq® fuel. Particle as well as hydrocarbon emissions from bioliq®/10 are significantly higher than in the case of RON95 E5. Increased particle emissions are attributed to the higher content of aromatics. Soot reactivity has been investigated and soot from bioliq®/10 exhibits higher reactivity than soot from RON95 E5.

Fast pyrolysis is the first step of the bioliq concept, which is developed at the Karlsruhe Institute of Technology (KIT) together with Air Liquide (Lurgi Technologies) for synthetic fuel production from lignocellulosic biomass via gasification. In the 2 MW bioliq fast pyrolysis pilot plant, shredded wheat straw is mixed with a hot heat carrier (sand) in a twin screw mixer reactor. At a temperature of 500 °C and in the absence of oxygen, the biomass particles are rapidly decomposed within seconds and pyrolysis gas, solids, and organic and aqueous condensates are produced. Representative results of the product yields and properties obtained from selected pyrolysis test campaigns from 2013 to 2015 are presented. It is shown that the mass ratio between the two liquid condensates can be adjusted by appropriate process design and operating conditions. Product stability is discussed, giving evidence that, by process internal recycling of the organic condensate, a controlled thermal maturing can be performed. It...

Oligomeric oxymethylene dimethyl ethers (OMDMEs, CH3O–(CH2O)n–CH3) are promising diesel fuel additives, which can reduce soot formation as well as NOx emissions. Due to the poor availability of high purity OMDMEs a comprehensive characterization of diesel standards was not feasible until now. Two types of oxymethylene dialkylethers (OMDMEs and oxymethylene diethyl ethers, OMDEEs) were synthesized, purified and characterized with respect to their physico-chemical and fuel properties. Density, melting point, flash point, auto ignition point as well as lubricity, kinematic viscosity and surface tension of OMDMEs and OMDEEs were measured and compared to the corresponding n-alkanes. Fuel requirements such as boiling points, flash points and surface tensions can be fulfilled by OMDMEs and OMDEEs. Furthermore, OMDMEs (n = 3–5) and OMDEEs (n = 2–4) are, due to their high cetane numbers of 124–180 and 64–103, particularly promising since cetane numbers in this range can lead to improved motor efficiency and smoother fuel combustion. Additionally, the heat of combustion as well as the standard enthalpy of formation and reaction were determined. Apart from somewhat lower heating values, OMDMEs exhibit fuel properties similar to conventional diesel complying the required fuel standards without the need of changing engines or fuel infrastructures.

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.

In regard to climate protection and saving of fossil resources, renewable and sustainable sources for energy, materials and chemicals are required. Among them, biomass is the only renewable carbon source and should be used preferentially for chemicals and materials production on a long term. Also, biomass can significantly contribute to mobility by different types of biofuels. By gasification of biomass or suitable bio-based intermediates the whole variety of today's fuels is accessible on a synthetic basis by appropriate syntheses such as Fischer–Tropsch or methanol reactions. In recent process developments, gasification, gas cleaning and conditioning and syntheses processes are conducted at elevated pressures up to 100 bar. Regarding the special features by using biomass as a feedstock, partly with high temperatures and at increased pressure a variety of specific scientific and technical questions arise along such a process chain. At the example of the bioliq ® pilot project actually developed at Karlsruhe Institute of Technology (KIT) for synthetic fuels production from biomass, spotlights are provided giving insight into the manifold multidisciplinary area of high pressure research and technology in this field of research and development. In this context, high pressure aspects in gasification, gas cleaning and synthesis of dimethyl ether (DME) are presented.

Zeolite-based bifunctional catalysts for the production of dimethyl ether (DME) from CO-rich synthesis gas (H2:CO = 1) were prepared via various preparation methods including co-precipitation–impregnation, impregnation, co-precipitation sedimentation and oxalate co-precipitation. The catalysts comprise a Cu/ZnO/Al2O3 component for methanol formation and zeolite H-MFI 400 as acidic component for methanol dehydration to DME. An admixed catalyst system was used as reference and all catalysts were characterized by SEM-EDX, XRF, N2-physisorption, XRD, H2-TPR, NH3-TPD, N2O-pulse chemisorption and TEM. The catalysts were tested in a continuously operating laboratory plant and the experiments revealed that the synthesis strategy strongly influences catalyst properties and hence catalyst activity. Especially a bifunctional catalyst prepared via oxalate co-precipitation proved to be highly active and could compete with conventional admixed catalyst systems. High CO-conversion and a high DME-selectivity could be reached. Catalyst characterization revealed that high Cu surface areas, small Cu particle sizes and a high number of moderate acidic sites are crucial to achieve maximum catalytic performance.

Fast pyrolysis is being increasingly applied in commercial plants worldwide. They run exclusively on woody biomass, which has favorable properties for conversion with fast pyrolysis. In order to increase the synergies of food production and the energetic and/or material use of biomass, it is desirable to utilize residues from agricultural production, e.g., straw. The presented method is suitable for converting such a material on an industrial scale. The main features are presented and an example of mass balances from the conversion of several biomass residues is given. After conversion, fractionated condensation is applied in order to retrieve two condensates - an organic-rich and an aqueous-rich one. This design prevents the production of fast pyrolysis bio-oil that exhibits phase separation. A two phase bio-oil is to be expected because of the typically high ash content of straw biomass, which promotes the production of water of reaction during conversion. Both fractionated condensation and the use of biomass with high ash content demand a careful approach for establishing balances. Not all kind of balances are both meaningful and comparable to other results from the literature. Different balancing methods are presented, and the information that can be derived from them is discussed.

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.