Institut für Chemie und Bioanalytik
Dauerhafte URI für die Sammlunghttps://irf.fhnw.ch/handle/11654/24
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Ergebnisse nach Hochschule und Institut
Publikation Liquid–liquid equilibria for trioctylamine/1-dodecanol/citric acid/water system at 303.1 and 308.1 K: Experimental data and prediction(American Chemical Society, 2020) Murcia-Montalvo, Laura; Pérez, Alan; Fontalvo, JavierThe present work experimentally tests the liquid–liquid equilibria (LLE) of aqueous citric acid (CA) solutions with trioctylamine (TOA) in 1-dodecanol at 303.2 and 308.2 K. A predictive model has been developed based on the experimental data. This model considers the physical dissolution of CA and complexation with TOA. At low CA concentrations, the stoichiometric ratio of acid/amine is (1:1). However, the acid/amine ratios of (1:1), (1:2), and (2:1) are present at high CA concentrations. The equilibrium constants for the different complexes were determined and compared to previous studies, which employed other organic solvents. The equilibrium constants obtained in this study are comparatively higher, making 1-dodecanol an attractive solvation medium. Also, the literature presents LLE experiments with contact times from minutes to hours. Because of this lack of consensus, this work displays experimental evidence to suggest contact and settling times required for experimental evaluation of the equilibria in liquid–liquid systems based on the standard deviation.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Influence of pulping conditions on the pulp yield and fiber properties for pulping of spruce chips by deep eutectic solvent(Springer, 2023) Pérez, Alan; Roy, Yagnaseni; Rip, Constantijn; Kersten, Sascha R. A.; Schuur, BoeloThe chemical pulping of wood chips using deep eutectic solvents (DES-pulping) has emerged as an alternative technology to conventional pulping in the paper industry, allowing the production of pulp in combination with the recovery of lignin and sugars for valorization. A challenge in the development of this technology is the understanding of how the operating conditions influence the crucial pulp manufacturing parameters such as delignification percentage, pulp yield, and fiber quality. This work is focused on investigating the effect of operating conditions such as cooking temperature, cooking time, liquor-to-wood ratio, initial water content on DES, type of mixing, the addition of a pre-treatment step (pre-impregnation of DES into the wood chips) to cooking process, and DES composition (lactic acid:choline chloride, lactic acid:sodium chloride, and lactic acid:sodium bromide) on the cooking of wood chips by DES. A shortcut quality evaluation parameter (Q), defined as the product of the fiber length and the degree of delignification quantified the quality of the pulping process in a single value, shows values similar to a reference unbleached kraft pulp for cooking at 130 °C in a range of cooking times from 3 to 4.5 h at a L/W of 10:1 by using lactic acid:choline chloride DES. More elaborate property analysis on the fibers showed that several of the the quality-indicating properties of the fibers (coarseness, shape factor, fibril area, and crill index) are comparable with typical sulfite pulping fibers.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Liquid extraction with immobilized liquids for product recovery from fermentation broths(Elsevier, 2022) Pérez, Alan; Gössi, Angelo; Riedl, Wolfgang; Schuur, Boelo; Fontalvo, Javier; Thatoi, Hrudayanath; Mohapatra, Sonali; Das, Swagat KumarNowadays, many fermentation chemicals are produced at an industrial scale. Numerous technological improvements have been developed and implemented to achieve high quality and quantity of fermentation products. However, several drawbacks in fermentation processes still limit their application at an industrial level. In situ product removal (ISPR) is a potential alternative to overcome the conventional drawbacks of the fermentative processes, increasing the fermentation's productivity and reducing the separation steps for recovery and purification. Currently, liquid extraction has emerged as a promising separation technology for ISPR, with immobilized liquids such as membrane-assisted extraction and microchannel liquid membrane, due to the high mass transfer rates, scalability, easy integration, and efficiency. This chapter will discuss these technologies regarding their integration into fermentative processes.04A - Beitrag SammelbandPublikation Die Chemie Pilotanlage der FHNW Muttenz(25.04.2023) Zogg, Andreas; Asprion, JonasDer Verein Miniplant 4.0 entwickelt im Process Technology Center an der FHNW neuartige Chemie-Pilotanlagen im Miniplant-Massstab. Der zentrale Scale-Down-Reaktor dient der präzisen Prozessentwicklung im Rührkessel. Insbesondere werden darin die lokalen thermischen Verhältnisse des Produktionsreaktors durch den Einsatz eines speziell designten Wärmetauschers exakt nachgebildet. Damit wird den Studenten und lokalen Unternehmen ein neuartiges Entwicklungswerkzeug zur Verfügung gestellt, welches einen schnelleren und präziseren Scale-Up von Produktionsverfahren direkt aus dem Labormassstab in den Produktionsreaktor erlaubt. Herr Prof. Dr. Andreas Zogg von der FHNW in Muttenz zeigt Ihnen den aktuellen Status der Anlage und die vielseitigen Schulungs- und Forschungsmöglichkeiten. Unterstützt wird er durch Herrn Dr. Jonas Asprion von der Firma Tool-Temp AG, welche die Kommerzialisierung der Temperierlösungen für Reaktormantel und Wärmetauscher anstrebt.06 - PräsentationPublikation New scale-up technologies for hydrogenation reactions in multipurpose pharmaceutical production plants(Schweizerische Chemische Gesellschaft, 2021) Furrer, Thierry; Müller, Benedikt; Hasler, Christoph; Berger, Bernhard; Levis, Michael Karl; Zogg, AndreasThe classical scale-up approach for hydrogenation reaction processes usually includes numerous laboratory- and pilot-scale experiments. With a novel scale-up strategy, a significant number of these experiments may be replaced by modern computational simulations in combination with scale-down experiments. With only a few laboratory-scale experiments and information about the production-scale reactor, a chemical process model is developed. This computational model can be used to simulate the production-scale process with a range of different process parameters. Those simulations are then validated by only a few experiments in an advanced scale-down reactor. The scale-down reactor has to be geometrically identical to the corresponding production-scale reactor and should show a similar mass transfer behaviour. Closest similarity in terms of heat transfer behaviour is ensured by a sophisticated 3D-printed heating/cooling finger, offering the same heat exchange area per volume and overall heat-transfer coefficient as in production-scale. The proposed scale-up strategy and the custom-designed scale-down reactor will be tested by proof of concept with model reactions. Those results will be described in a future publication. This project is an excellent example of a collaboration between academia and industry, which was funded by the Aargau Research Fund. The interest of academia is to study and understand all physical and chemical processes involved, whereas industry is interested in generating a robust and simple to use tool to improve scale-up and make reliable predictions.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation One-pot microwave synthesis of Pd modified titanium dioxide nanocrystals for 3D aerogel monoliths with efficient visible-light photocatalytic activity in a heated gas flow reactor(Royal Society of Chemistry, 01.01.2022) Kwon, Junggou; Choi, Kyoungjun; Tervoort, Elena; Niederberger, MarkusHarvesting solar energy and efficiently converting it into a chemical energy carrier like hydrogen (H2) is an important topic in photocatalysis. Here, we present a fast and simple approach for the one-pot synthesis of crystalline semiconductor nanoparticles modified with co-catalysts that can be used as nanobuilding blocks for nanoparticle-based aerogels with excellent visible-light photocatalytic activity. The microwave-assisted nonaqueous sol–gel method allows titanium dioxide (TiO2) nanoparticles to be synthesized and modified with palladium (Pd) ions and Pd metal nanoparticles in a single step. Their assembly into aerogel monoliths preserves the modified properties of the TiO2 nanobuilding blocks, resulting in morphological properties that are advantageous for the photocatalytic H2 production from methanol (CH3OH) oxidation. By controlling the amount of Pd doping and Pd nanoparticle loading, the nanoparticle-based aerogels showed significantly improved photoexcited charge generation and separation efficiency under visible light. In addition, we present a novel reactor design specifically developed for 3D aerogel monoliths that allows control of light intensity, gas flow, reactant concentration, and temperature, enabling the study of all key experimental parameters to optimize photocatalytic H2 production. The visible light absorbed by the aerogels was found to be the driving force behind the efficient photocatalytic activity. Our Pd modified TiO2 nanoparticle-based aerogels achieved H2 production rate of 117.5 mmol g−1 h−1 with good stability for 3 days under visible light thanks to the prevention of carbon monoxide (CO) poisoning. The simultaneous optimization of the material composition and the matching photoreactor form the decisive basis for getting the most out of monolithic 3D photocatalysts.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation New Scale-Up Technologies for Hydrogenation Reactions in Multipurpose Pharmaceutical Production Plants(Hochschule für Life Sciences FHNW, 2022) Zogg, Andreas; Furrer, Thierry05 - Forschungs- oder ArbeitsberichtPublikation Thermokinetic model of hydroxylamine decomposition in the catalytic oxidation of ammonia with titanium silicalite-1(Hochschule für Life Sciences FHNW, 23.10.2020) Walthert, Florian; Zogg, Andreas; Fabian Meemken LonzaHydroxylamine is a key molecule for some important chemical processes. An example is the synthesis of ε-caprolactam, which is required for the production of Nylon. Since hydroxylamine decomposes thermally, its transport and storage are problematic. It is also problematic for the synthesis of hydroxylamine from ammonia with titanium silicalite-1. The goal of this study was to investigate the exothermic decomposition reaction. The heat of the reaction was measured in multiple DSC experiments. During the decompo sition, vast quantities of gases are released. To measure the pressure rise, an explosion reactor was employed. Three reaction hypotheses have been tested. With the use of a mathematical model one hypothesis could be proven. The material in uence on the de composition reaction was examined for PEEK, stainless steel and hastelloy C22. From the DSC measurements, a descriptive model and isoconversional kinetics were obtained.11 - Studentische Arbeit