Time: September 19th, 2017, 14:00-15:00
Venue: Conference Room on First Floor in No.1 Energy Building
Lecturer: Professor Stuart Taylor
Abstract:
Heterogeneous catalysts are used widely in many applications, from protection of the environment for emission control to manufacture of many important chemicals and intermediates. Around 80% of all manufactured goods will have employed a catalyst somewhere in one of the steps of their production, and they are employed for over 95% of chemical production. Hence catalysts and their use contribute significantly to the world’s economy and society. There are a number of methods available for catalyst preparation, and the method used will have an important influence on the catalyst composition, structure and morphology. These factors are crucial in determining the performance of a catalyst, and hence the method of catalyst preparation will have a direct influence on its effectiveness. For the preparation of mixed metal oxide catalysts, methods such as mechanochemical, sol-gel or hydrothermal synthesis can all be used, but one of the most commonly used is coprecipitation. Coprecipitation is a relatively simple process to operate, and can be used to prepare catalyst precursors with well-mixed composition, and it is employed industrially. However, coprecipitation results in large volumes of aqueous effluent that contains metal ions, nitrates and carbonates, and this has to be treated.
We have pioneered an alternative catalyst preparation method that is supercritical anti-solvent (SAS) precipitation. SAS employs supercritical carbon dioxide as an anti-solvent. The precursors for the catalyst are dissolved in an organic solvent and then mixed with supercritical carbon dioxide. The fast diffusion of supercritical carbon dioxide into the solvent rapidly causes precipitation. The SAS process is able to produce materials with structures and morphologies that cannot be made readily using other methods, providing a powerful tool to aid in the discovery of new heterogeneous catalysts. We have successfully applied the SAS process to prepare a range of novel catalysts, including catalyst supports; and single and mixed metal oxide catalysts. A number of examples will be presented and discussed. In particular our latest work has focused on preparation of copper zinc oxide catalysts, which are important industrially for methanol synthesis and low temperature water gas shift reactions. Supercritical preparation is able to make a rare georgeite phase, which has not been previously studied. A catalyst produced from the georgeite phase is exceptionally active and the story of this catalyst will be presented.
Introduction:
Professor Stuart Taylor obtained his BSc Hons in Chemistry from Brunel University in 1991, and during this time he also completed 18 months of industrial placements with ExxonMobil, ICI and Shell. In 1991 he moved to the University of Liverpool to study for his PhD at the Leverhulme Centre for Innovative Catalysis, focussing on the direct selective oxidation of methane to methanol, funded by the Gas Research Institute, Chicago. After obtaining his PhD he remained in Liverpool, first as a postdoc and later as a Principal Scientist funded by BNFL. He was appointed to Cardiff University as a Lecturer in October 1997, promoted to Senior Lecturer in 2007, Reader in 2010and Professor in 2013.
He has an internationally recognised research profile, and his research is based around heterogeneous catalysis, with a focus on oxidation, both for environmental applications and chemical production. He collaborates widely, both nationally and internationally with a number of research groups and research institutes. He also interacts extensively with industry; some examples of recent and current partners are ExxonMobil, Dow, Johnson Matthey, Jaguar Land Rover, Invista, General Motors, Sabic, Henkel and Sasol. He has published over 250 papers and patents in the field of heterogeneous catalysis. He is the Head of the Catalysis and Interfacial Science Section at Cardiff School of Chemistry, Deputy Director of the Cardiff Catalysis Institute, Deputy head of School and Director of Research.
Contact: ZHAO Xiaochen, 1502 Group
Phone: 84379416