TY - CONF A1 - Radnik, Jörg T1 - Synchrotron radiation as a tool in applied catalytic research N2 - Synchrotron Radiation with its high intensity and the opportunity to tune the wavelength offers unique possibilities to investigate real catalysts, even under industry-like conditions. A good example is a XAFS study performed at supported Ni catalysts used for the dimerization of butene at elevated temperature and pressure. Another example are investigations at titania supported Pd based catalyst elucidating the role of co-components (e.g. Sb, Co, Mn and Au) which are necessary to get the desired promising performance in the gas phase acetoxylation of toluene to benzyl acetate, an environmentally benign alternative for the conventional process using chlorine. Furthermore, investigations about the redox properties of different Cu catalysts will be presented. It could be shown that the redox properties of Cu have a great impact on the performance of such catalysts, not only in some gas phase reactions, but also in photocatalytic applications, e.g. water splitting. T2 - EMIL Seminar CY - Berlin, Germany DA - 23.01.2017 KW - Catalysis KW - Synchrotron radiation KW - Nanochemistriy PY - 2017 AN - OPUS4-39026 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radnik, Jörg A1 - Dang, Thi Thuy Hanh A1 - Gatla, Suresh A1 - Ruguwanshi, A1 - Hoell, Armin T1 - Redox properties of Cu ions in molecular sieves N2 - Molecular sieves as materials with defined pores offer new opportunities in the preparation of nanostructured materials for different applications in chemistry, medicine and biology. Typical examples for such materials are zeolites, porous glass, different silicas and active carbon. Introducing transition metal ions in such materials can widen the possibilities of these materials in terms of chemical activity. Especially, the opportunity to tailor the redox properties of the transition metal ions by varying the location of the ion in the sieves is a promising way to obtain catalysts with the desired properties. For this purpose, Cu2+ ions were introduced into a SAPO-5 (silicoaluminaphosphate) by a hydrothermal method and by impregnation. As expected, the different preparation methods led to different locations of the Cu2+ ions: by the hydrothermal method the ions were incorporated in the SAPO-5 framework, by impregnation mononuclear Cu species randomly distributed in the pores of the support or CuO particles were formed depending on the Cu amount. These locations could be determined by Extended X-ray Absorption Fine Structure and Anomalous Small-Angle X-ray Scattering investigations. For investigating the redox properties of the Cu2+ ions the differently prepared sample were treated in Ar and H2 atmosphere until 550°C. X-ray Photoelectron Spectroscopy was performed to study the valence states of Cu after each of such treatment. For a definite determination of the valence states, both Cu 2p and Cu LMM spectra must be recorded. Cu2+ exhibits a clear chemical shift and a typical satellite structure in Cu2p spectra, but between mono- and zerovalent Cu a differentiation is not possible. On the other hand, these two species show a clear shift in the Auger spectra. Whereas in H2 atmosphere in any case metallic Cu was formed, the treatment in Ar showed significant differences between the samples. Cu2+ incorporated in the framework could not be reduced by this treatment. In contrast, the mononuclear Cu2+ species were reduced to stable Cu+. Likewise, the CuO nanoparticles were reduced to the monovalent Cu, but this species can be much more easily reoxidized in air. The consequences for the catalytic properties will be discussed. T2 - ECASIA 2017 CY - Montpellier, France DA - 24.09.2017 KW - Catalysis KW - X-ray photoelectron spectroscopy KW - Nanostructured materials PY - 2017 AN - OPUS4-42323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maiwald, Michael T1 - How Online NMR Spectroscopy Accelerates Chemical Process Development and Manufacturing – From Automated Spectral Analysis to Integrated NMR Micro Reactors N2 - Accelerating chemical process development and manufacturing along with quick adaption to changing customer needs means consequent transformation of former batch to continuous (modular) manufacturing processes. These are justified by an improved process control through smaller volumes, better heat transfer, and faster dynamics of the examined reaction systems. As an example, for such modular process units we present the design and validation of an integrated nuclear magnetic resonance (NMR) micro mixer tailor‐made for a desired chemical reaction based on computational modelling. The micro mixer represents an integrated modular production unit as an example for the most important class of continuous reactors. The quantitative online NMR sensor represents a smart process analytical field device providing rapid and non‐invasive chemical composition information without need for calibration. We describe the custom design through computational fluid dynamics (CFD) for the demands of the NMR sensor as well as for the given reaction conditions. The system was validated with an esterification reaction as an example for a chemical reaction process. Systems utilizing such an online NMR analyser benefits through short development and set‐up times based on “modular” spectral models. Such models can simply be built upon pure component NMR spectra within minutes to a few hours (i.e., assignment of the NMR signals to the components) instead of tedious DoE calibrations runs. We present a range of approaches for the automated spectra analysis moving from statistical approach, (i.e., Partial Least Squares Regression) to physically motivated spectral models (i.e., Indirect Hard Modelling and Quantum Mechanical calculations). The approach was validated for typical industrial reactions, such as hydrogenations or lithiations. T2 - Wissenschaftliches Kolloquium des Leibniz-Institut für Katalyse e. V. an der Universität Rostock CY - Rostock, Germany DA - 09.10.2019 KW - Process Analytical Technology KW - Reaction Monitoring KW - Online NMR Spectroscopy KW - Data Analysis KW - Digitization KW - Catalysis PY - 2019 AN - OPUS4-49238 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -