DECHEMA

About: DECHEMA is a nonprofit organization based out in Frankfurt am Main, Germany. It is known for research contribution in the topics: Corrosion & Oxide. The organization has 756 authors who have published 1307 publications receiving 25693 citations.

Theoretical considerations on phase boundary reactions and mass transfer during the oxidation of iron

Abstract: The layered system Fe/FeO/Fe3O4/Fe2O3/O2 is formed during the oxidation of iron in air or oxygen at temperatures above 580°C. Phase transformations as well as transfer of ions, electrons, and vacancies occur at the phase boundaries; these phenomena have not been fully described in the literature. Equations are given in this paper which allow a complete estimation of the rates of all partial reactions. Fe3O4 is formed by phase transformation of Fe2O3. The formation of Fe2O3 is described theoretically, but a decision from which of several reactions Fe2O3 is really formed is not possible because of experimental difficulties.

Direct synthesis of hydrogen peroxide over supported Pd catalysts: Turning to dense CO2 as an alternative solvent

Abstract: An approach for the direct synthesis of hydrogen peroxide with CO2 as solvent has been explored. Both batch and continuous experiments have been performed. The activity of self-prepared Pd-supported catalysts has been verified leading to high productivity of up to 132 g H 2 O 2 g Pd − 1 h − 1 in batch with selectivities of up to 70%. However, the use of dense CO2 in batch set back catalyst activity leading to the formation of H2O as the only product. For the continuous process in dense CO2 increased performance in terms of productivity with up to 26 g H 2 O 2 g Pd − 1 h − 1 with low selectivity were achieved.

Inhomogeneous distribution of fixed enzymes inside carriers

Abstract: Waterinsoluble catalysts with high activity and homogeneous enzyme distribution show low efficiency when using low substrate concentrations, high molecular weight substrates of unbuffered systems. This paper presents an optimised.catalyst design by introducing inhomogeneous enzyme distribution throught the matrix which leads to higher efficiencies.