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This article introduces a new high-pressure process for the gentle drying, micronisation and formulation of high molecular mass gelatine. Spray drying of gelatine solutions is a well-established process for very low molecular weight gelatine, aqueous solutions containing low gelatine concentrations or gelatine solutions containing viscosity reducing additives. In the introduced process, supercritical CO2 was applied to micronised aqueous gelatine solutions and was then expanded from high pressure into a spraying chamber to remove the water content by extraction and evaporation under moderate conditions. The resulting product was analysed using common powder analysis methods. Aqueous gelatine solutions with a dry mass content of up to 50 wt.-percent with a molecular mass of 156,000 g mol-1 were pulverised and dried with this process, with only limited degradation by hydrolysis during processing.

Phase equilibria of carbon dioxide + poly ethylene glycol (PEG) of average mol weight 6000 g/mol + water mixtures has been measured by the static method at conditions of interest for the development of Particles from Gas Saturated Solutions (PGSS)-drying processes (pressure from 10 MPa to 30 MPa, temperature from 353 K to 393 K). A thermodynamic model based on the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) equation of state has been developed for correlating experimental data. The model is able to predict the composition of the liquid phase with an average deviation of 8.0%. However, the model does not calculate correctly the concentration of PEG in the gas phase. The model is also capable of predicting VLE data reported in the literature of PEG + CO2 mixtures with PEGs of molecular weights ranging from 1500 g/mol to 18500 g/mol as well as solid-fluid equilibrium of carbon dioxide + PEG mixtures at pressures below 10 MPa.

"Micronization processes using the unique properties of supercritical fluids (SCF) have reached a state, where they are entering industrial application. Results fromalmost 3 decades of basic research concerning thermodynamics and mass transfer during solidification in presence of SCF have been applied to develop a multitude of process ideas. Selected processes from the anti-solvent- and PGSS-type have been scaled up and are successfully operated. The key to success was not only to develop the technologies and to demonstrate their technical and economical feasibility but also to generate newconcepts for applications in the food area. Selected examples will be presented and the achievements and challenges still to be met are summarized."

"In spite of high prices for fossil raw materials the production of biomass-based products is rarely economically successful today. Depending on the location feedstock prices are currently so high that products from renewable resources are not marketable when produced in existing process chains. Apart from the higher feedstock costs one reason is that at present no optimized production systems exist in contrast to the chemical and petrochemical industry where these systems have been established over the last decades. If we succeed in developing production systems modelled on those of petroleum refineries where we can provide a flexible coupled production of energy, fuels, materials and chemicals chances are good to enable a lastingly successful production on the basis of renewable resources. Based on examples of fat-based and sugar-based concepts ideas for platform oriented biorefineries are outlined."

Die Gerbzeit soll unter Kohlendioxideinfluss reduziert werden. Diese Prozesszeitverkürzung hat einen geringeren Energieaufwand und zudem eine geringere Kapitalbindung durch schnellere Durchlaufzeiten der tierischen Häute in der Gerberei zur Folge.

"In diesem Beitrag wird das PGSS-Verfahren (Particles from Gas Saturated Solutions) zur Herstellung von pulverförmigen Kompositen mit vollkommen neuen Eigenschaften vorgestellt. Es können beliebig viele verflüssigbare Feststoffe in einer Lösung gemischt und zu rieselfähigem Pulver verarbeitet werden. Dabei werden überkritische Fluide als Hilfsstoffe genutzt. Diese Hilfsstoffe werden dazu verwendet, um niedrig- bis hochviskose Substanzen, wie z. B. Schokolade, Klebstoff oder Lack zu versprühen und dann erstarren zu lassen. Das PGSS-Verfahren kann sowohl kontinuierlich als auch diskontinuierlich (Batch-Betrieb) durchgeführt werden."

Einen mit Erdnussöl betriebenen Motor stellte Rudolf Diesel bereits zur Weltausstellung 1900 in Paris vor. Der Motor wurde ein Welterfolg, doch der Pflanzensprit geriet über Jahrzehnte in Vergessenheit. Heute steigt die Zahl der Kunden an den rund 1700 Biodieseltankstellen in Deutschland allmählich an, aber bis wir wirklich umweltgerecht und wirtschaftlich Biokraftstoffe tanken können und Kunststoffe auf rein pflanzlicher Basis zur Verfügung stehen, ist es noch ein weiter Weg. Mit der Bioraffinerie, die beides kann, setzen Forscher jetzt auf übergreifende Konzepte.

Phase equilibria in the binary polymer-gas systems polyethyleneglycol (PEG)-propane, PEG-nitrogen and PEG-carbon dioxide have been investigated. The experiments were performed for PEG with molecular weights of 200, 1500, 4000 and 8000 g/mol in a temperature range of 50 to 120°C and a pressure range from 5 to 300 bar using a static-analytical method. It was found that carbon dioxide dissolves much better in PEG than does propane or nitrogen. With rising temperature the PEG-carbon dioxide miscibility gap increases, whereas the miscibility gaps of the PEG-propane and the PEG-nitrogen systems decrease. The influence of the polymer molecular weight on the gas solubility is almost negligible for PEG 1500 to PEG 8000. The behaviour of the small PEG 200 deviates significantly due to strong endgroup influence. The gas solubilities in the polymers are correlated with the SAFT equation of state. The influence of temperature and of PEG molecular weight is represented satisfactorily.

Microsporidian spores of Trachipleistophora hominis Hollister, isolated from a human, readily infected larval stages of both Anopheles quadrimaculatus Say sensu lato and Culex quinque-fasciatus Say. Mosquito infections with T. hominis were located, primarily, in abdominal muscles in segment numbers 4 through 6; other spores were found in the hemocoel and proboscis. Nearly 50% of the infected mosquito larvae survived to the adult stage. Spores recovered from adult mosquitoes were inoculated into mice and resulted in significant muscle infection at the site of injection. Preliminary observations also showed that T. hominis spores can be passively transferred from infected mosquitoes to a sugar water substrate.

Phase equilibria (solid-liquid-gas) for polyethyleneglycol (with molar masses 1500, 4000, 8000 and 35 000 g mol -1) and carbon dioxide mixtures were determined. It was found that the S-L-V lines in P-T projection for all polyethyleneglycols studied show a temperature minimum and a temperature maximum. These phenomena have not been reported previously in the literature. If a reduced temperature (obtained by dividing the temperature of the solid-liquid transition under pressure by the melting point of PEG at 1 bar) is introduced, the S-L transition of all binary systems are represented by one line. The solubility of CO2 in liquid polyethyleneglycols is influenced by pressure and temperature, and is almost independent of the molecular mass of polyethyleneglycol. In a P-T projection, the vapour-liquid equilibrium is represented by a straight line if isopleths are plotted as a function of the reduced temperature. By combining the P-Tred projections of the S-L and L-V transitions, one master diagram can obtained which is valid for all binary mixtures of polyethyleneglycol and CO2 in the pressure and temperature range investigated.

The polar filaments within microsporidian spores discharges as tubes with subsecond velocity. Populations of discharging tubes of Glugea hertwigi spores pulse-labeled with latex particles for 1-3 s were consistently devoid of label at the distal ends; discharging tubes were completely labeled after 30- to 60-s exposure to latex. This experiment indicates that discharge tubes grow at the tip. Completely assembled discharge tubes consisted of single, empty cylinders; however, incompletely discharged tubes had a cylinder-within-a-cylinder profile at the distal ends. This observation indicates that the discharge tube material emerges at the distal end by an eversion process. Finally, studies with cinematic Nomarski interference optics of spore tubes extruding across a water-air interphase indicate that all the material emerging from the growing tip of the tube is incorporated into the wall of the discharge tube. Evidence indicates that the polar filament of undischarged spores is a homogeneous coil of polar tube protein equivalent to the polar tube protein in discharged tubes.

Energy systems are evolving rapidly around the world, driven mainly by CO2-e reduction targets. This has led to opportunities for integrated low carbon electricity-and-fuel systems founded on large scale “Power-to-Hydrogen, Hydrogen-to-X” (PtH-HtX). Power-to-Hydrogen (PtH) refers to large scale electrolysis. Hydrogen-to-X (HtX) refers to a range of high value products and services. If these pathways start with low-carbon electricity, then the fuel consumed at the downstream end also low-carbon. Use of intermittently low valued power lowers all production costs. This paper specifically identifies the main pathways and interconnections in a way that overcomes the ambiguities inherent in the term “Power-to-Gas”. In turn, this provides solid and easier to understand foundations for building legal and regulatory frameworks for new business opportunities along the lengths of the numerous pathways from supply to consumption.

Research carried out within the framework of Task 38 of the Hydrogen Implementing Agreement of the International Energy Agency. The task is coordinated by the Institute for techno-economics of energy systems (I-tésé) of the CEA, supported by the ADEME. The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. With the expansion of renewable energy’s contribution to the energy mix, balancing the electricity grid is becoming increasingly challenging. Alongside other solutions, Power-to-Hydrogen concepts are gaining significant interest. In this paper, the “Task 38”, initiated by the Hydrogen Implementing Agreement of the International EnergyAgency, presents the first of a two-step literature review regarding Power-to-Hydrogen and Hydrogen-to-X concepts with a focus on prospective market and economic potential. The study reveals a large scope of literature that shows a considerable variety ofsuggested implementation schemes. The transportation sector is identified as the most promising consumer market. Hydrogen-to-Gas pathways will require subsidies in order to be profitable. Hydrogen-to-Power becomes an economically promising option in the context of systems with high shares of renewables and a need for longer-term storages. Additionally, key enablers for Power-to-Hydrogen concepts are identified; namely support policies, concurrently with ongoing progress on the development and implementation of industry standard.