Institut für Chemie und Bioanalytik
Dauerhafte URI für die Sammlunghttps://irf.fhnw.ch/handle/11654/24
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Publikation Continuous in situ lactic acid extraction from sweet whey fermentation broth using a tubular membrane contactor(2022) Demmelmayer, Paul; Pérez, Alan; Riedl, Wolfgang; Kienberger, MarleneBackground Whey, as the major dairy by-product, has become a severe problem for the dairy industry because its demand has decreased, while its production has increased in the past years. Since the high demand for dairy products tends to further increase, suitable routes for whey valorization are required. Whey contains valuables like lactate, but due its composition matrix, processing is challenging. The high sugar content in whey makes it a potential feedstock to produce lactic acid (LA) via microbial fermentation. Still, the known drawbacks of biotechnological LA production, such as growth inhibition by the product, the use of neutralizers, low productivity, and high overall costs of the process must be overcome. In situ LA recovering using a suitable separation technology is a potential strategy to overcome the mentioned drawbacks. In this work, the in situ LA extraction from a whey fermentation broth was evaluated. Sweet whey was used as feedstock for lactic acid production via microbial fermentation, while LA was recovered by reactive liquid-liquid extraction using a tubular membrane contactor. Method The feed material used in this work is a fermentation broth from sweet whey, which was filtered prior to extraction experiments using microfiltration. In a first series of experiments, two-phase extraction experiments were conducted in temperature controlled separation funnels, to investigate different solvent phase combinations for the lactic acid extraction. Special attention was paid to replace commonly applied fossil-based solvents with green alternatives, such as deep eutectic solvents (DES). After extraction, the extract was treated in a back-extraction step to recover LA from the solvent phase. Here, an anti-solvent, e.g. heptane or p-cymene, was used to transfer LA to the receiving phase, which was water. Afterwards the performance of reactive liquid-liquid extraction of LA using a PTFE membrane contactor was evaluated by using two potential solvent phases, namely tri-n-octyl amine (TOA) with n-decanol and a DES formed from thymol and menthol. From the experimental results the overall mass transfer coefficient was calculated based on a rigorous mass transfer model to predict the LA concentration in both phases. Finally, performance of the in situ LA recovery from sweet whey by using membrane contactor was investigated from both, experimentally and theoretically points of view. Results & Conclusion In the two-phase extraction experiments, the reactive extractants Aliquat336, TOA, trioctylphosphinoxid (TOPO), and the mixture Aliquat336/TOA were found to be most efficient with the diluents 1-decanol, limonene, and a deep eutectic solvent consisting of thymol and menthol. Especially, the DES and limonene are promising as they can be produced from renewable resources. With respect to back-extraction, heptane and p-cymene showed the highest efficiencies for transferring lactic acid into the receiving phase water. In the next step, the selected solvents were used to perform LA recovery in the tubular membrane contactor from a model aqueous solution of LA and a fermentation broth of sweet whey. The proposed technology for valorizing dairy waste through LA biotechnological production shows the feasibility to scaling it up.06 - PräsentationPublikation Using membrane-supported liquid–liquid extraction for the measurement of extraction kinetics(Swiss Chemical Society, 2011) Riedl, Wolfgang; Mollet, Daniel; Grundler, GerhardMembrane-supported liquid–liquid extraction uses artificial membranes for the generation of a phase interface between the two liquid phases involved in extraction. Additional equipment for the generation of droplets as well as phase separation afterwards is no longer necessary. Since the membranes used for this special type of extraction are quite well described concerning thickness, porosity, tortuosity and material it is possible to generate information about the diffusion coefficient of the component to be extracted within the preferred solvent from extraction trails easily. This article describes an experimental set-up for both the proof of principle of membrane-supported liquid–liquid extraction and, using a dedicated computer-aided data treatment, how to calculate the overall mass transfer coefficient as well as the diffusion coefficient for a given system within moderate testing duration.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Energy-related chemical research at the universities of applied sciences(Swiss Chemical Society, 2013) Riedl, Wolfgang; Fischer, Fabian; Marti, Roger; Brühwiler, DominikAn overview of current activities in the field of energy-related chemical research at the Swiss Universities of Applied Sciences is presented.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Sustainable Chemistry at the Universities of Applied Sciences(Swiss Chemical Society, 2012) Sanglard, Pauline; Rogano, Frank; Naef, Olivier; Riedl, Wolfgang; Crelier, Simon; Fischer, Fabian; Morganti, Franziska; Hinderling, ChristianAn overview of activities in the field of sustainable or 'green' chemistry at the Universities of Applied Sciences in Switzerland is presented.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Prozessoptimierung von 4 Stufen zur Herstellung eines Pharma-Zwischenprodukts(Hochschule für Life Sciences FHNW, 2024) Güner, Merve; Zogg, Andreas11 - Studentische ArbeitPublikation Development of a tool for the automated visualization of batch recipes(Hochschule für Life Sciences FHNW, 2024) Gentner, Jannick; Zogg, Andreas; Bachem AG11 - Studentische ArbeitPublikation Scaling down the heat transfer in multipurpose plants(26.06.2024) Zogg, Andreas04B - Beitrag KonferenzschriftPublikation Kontinuierliche Ethoxylierung(25.04.2024) Zogg, Andreas; Zahnd, This; Brönnimann, BenediktModellbasiertes Sicherheitskonzept für die Entwicklung einer kontinuierlichen Ethoxylierung. Modellvalidierung mittels kontinuierlichem Kalorimeter innerhalb einer Glove-Box.06 - PräsentationPublikation Enzymes for consumer products to achieve climate neutrality(Oxford University Press, 2023) Molina-Espeja, Patricia; Sanz-Aparicio, Julia; Golyshin, Peter N.; Robles-Martín, Ana; Guallar, Víctor; Beltrametti, Fabrizio; Müller, Markus; Yakimov, Michail M.; Modregger, Jan; van Logchem, Moniec; Corvini, Philippe; Shahgaldian, Patrick; Degering, Christian; Wieland, Susanne; Timm, Anne; de Carvalho, Carla C. C. R.; Re, Ilaria; Daniotti, Sara; Thies, Stephan; Jaeger, Karl-Erich; Chow, Jennifer; Streit, Wolfgang R.; Lottenbach, Roland; Rösch, Rainer; Ansari, Nazanin; Ferrer, ManuelToday, the chemosphere’s and biosphere’s compositions of the planet are changing faster than experienced during the past thousand years. CO2 emissions from fossil fuel combustion are rising dramatically, including those from processing, manufacturing and consuming everyday products; this rate of greenhouse gas emission (36.2 gigatons accumulated in 2022) is raising global temperatures and destabilizing the climate, which is one of the most influential forces on our planet. As our world warms up, our climate will enter a period of constant turbulence, affecting more than 85% of our ecosystems, including the delicate web of life on these systems, and impacting socioeconomic networks. How do we deal with the green transition to minimize climate change and its impacts while we are facing these new realities? One of the solutions is to use renewable natural resources. Indeed, nature itself, through the working parts of its living systems, the enzymes, can significantly contribute to achieve climate neutrality and good ecological/biodiversity status. Annually they can help decreasing CO2 emissions by 1–2.5 billion-tons, carbon demand by about 200 million-tons, and chemical demand by about 90 million-tons. With current climate change goals, we review the consequences of climate change at multiple scales and how enzymes can counteract or mitigate them. We then focus on how they mobilize sustainable and greener innovations in consumer products that have a high contribution to global carbon emissions. Finally, key innovations and challenges to be solved at the enzyme and product levels are discussed.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Modeling-based approach towards quality by design for a telescoped process(Schweizerische Chemische Gesellschaft, 2024) Zahnd, This; Kandziora, Maja; Levis, Michael K.; Zogg, AndreasA telescoped, two-step synthesis was investigated by applying Quality by Design principles. A kinetic model consisting of 12 individual reactions was successfully established to describe the synthesis and side reactions. The resulting model predicts the effects of changes in process parameters on total yield and quality. Contour plots were created by varying process parameters and displaying the model predicted process response. The areas in which the process response fulfils predetermined quality requirements are called design spaces. New ranges for process parameters were explored within these design spaces. New conditions were found that increased the robustness of the process and allowed for a considerable reduction of the used amounts of a reagent. Further optimizations, based on the newly generated knowledge, are expected. Improvements can either be direct process improvements or enhancements to control strategies. The developed strategies can also be applied to other processes, enhancing upcoming and preexisting research and development efforts.01A - Beitrag in wissenschaftlicher Zeitschrift