Shell Professor of Chemical Engineering
Pro-Vice-Chancellor for Research
BSc, Chemical Physics, University of Bristol, 1982
Ph.D, Physical Chemistry, University of Cambridge
1987 Beilby Medal, 1995 Miller Visiting Professor, University of California, Berkeley, 1996 Tilden Lectureship and Silver Medal of the Royal Society of Chemistry, 2000.
My group’s primary research interest is in the development of magnetic resonance techniques to study research problems of relevance to chemical engineering. Understanding multi-component adsorption, diffusion, flow and reaction processes is central to designing and optimising processes and products in chemical engineering and biotechnology. Magnetic resonance and, in particular, magnetic resonance imaging (MRI) is uniquely placed to give us new insights into complex systems because it can quantify both transport processes and chemical composition. However, translating this measurement technology to applications in non-medical environments requires further development of existing magnetic resonance methodologies. The group is made up of people with diverse research backgrounds and interests, some focusing on the development of methods whilst others are more motivated to apply MRI to solve particular applications problems. Areas of particular interest to us are:
Next-generation MR techniques: Our activities in this area are focussed on collaboration with Microsoft Research in which we are novel k-space sampling techniques, compressed sensing methods and Bayesian analysis to reduce data acquisition times. This is useful for two reasons: (i) we can image with higher time resolution, (ii) we can acquire image data at higher spatial resolution. These approaches also open up opportunities in translating measurements currently performed at high magnetic field strength across to low field technology – so-called portable devices which can be used ‘on the plant’ or ‘in the field’. We are currently using these new methods to study multi-phase flows and hydrodynamics in chemical reactors.
Catalysis: The MRRC provides us with a range of magnetic resonance techniques to study catalytic systems. These techniques include solid state NMR spectroscopy, pulsed field gradient studies of molecular diffusion, and magnetic resonance imaging of chemical composition and hydrodynamics within the reactor. Specific projects address the spatial mapping of catalyst deactivation and measurement of mass transfer limitations within a reactor. Our ultimate goal is to perform all these measurements in situ during reaction. If such measurements can be made, the integrated design of catalyst and reactor becomes possible. In addition to magnetic resonance we also used tapered element oscillatory microbalance techniques to study the dynamics of adsorption, desorption and carbon laydown. We also have an emerging interest in applying THz-TDS to characterise catalytic systems. Magnetic resonance data are also be used to aid the development of lattice-Boltzmann and Computational Fluid Dynamics (CFD) codes – this is an increasingly active area of research for us.
Terahertz: The THz region of the electromagnetic spectrum lies between the infra-red and microwave. This is a relatively new research area because easy-to-use sources and detectors of THz radiation have only been developed quite recently. Therefore, there should be some exciting research to be done exploiting this new frequency range! THz is a vibrational spectroscopy which probes low-frequency modes, typical of inter-molecular modes in liquids and solids. We are exploring possible applications in the characterisation of pharmaceutical materials, and the use of THz as a process analytics tool in this field. At a more fundamental level, we collaborate with Dr Graeme Day in the Department of Chemistry to assign modes to specific features in the THz spectrum. Research of this type is essential if we are to be able to use THz as a spectral analysis tool as opposed to using it as a tool for ‘fingerprint’ recognition of particular molecular species. A further line of research is in using Quantum Cascade Lasers (QCLs) to develop 3-D imaging protocols.
Oil Recovery: Magnetic resonance has long been used in the oil drilling sector as a method for assessing the fluid composition within oil-bearing rocks. Whilst our overall objective is to develop new measurement protocols which can be used on low-field well-logging tools, we are also very interested in the fundamental physics of fluid flows in porous media. Magnetic resonance is a particularly powerful technique for characterising the pore structure and multi-phase flows within rock strictures. Particular projects address topics such as the optimisation of treatment fluids for oil recovery applications. For example, we can use MR to explore how the treatment fluid moves and deposits within the rock so that we can optimise its properties to maximise the oil recovery from the rock, and water retention within the rock, during an extraction process.
Processing-Structure-Function Relationships in Pharmaceutical Delivery Systems: Whilst much time and energy is spent on producing and manufacturing the drug or ‘active’ for treatment of a particular condition, the actual efficacy of the drug can be influenced significantly by the delivery matrix into which it is incorporated for introduction to the patient. We use a range of magnetic resonance micro-imaging and diffusion mapping techniques to help aid the design and manufacture of these delivery systems, and also to aid the development of numerical tools to predict drug dissolution profiles.
M.H. Sankey, D.J. Holland, A.J. Sederman and L.F. Gladden, "Magnetic resonance velocity imaging of liquid and gas two-phase flow in packed beds". J. Magn. Reson. 196, 142-148, 2009.
K.L. Nguyen, T. Friscic, G.M. Day, L.F. Gladden and W. Jones, "Terahertz time-domain spectroscopy and the quantitative monitoring of mechanochemical cocrystal formation". Nature Materials 6, 206-209, 2007.
L.D. Anadon, A.J. Sederman and L.F. Gladden, "Mechanism of the trickle-to-pulse flow transition in fixed-bed reactors". AIChE Journal 52, 1522-1532, 2006.
D. Teschner, E. Vass, M. Havecker, S. Zafeiratos, P. Schnorch, H. Sauer, A. Knop-Gericke, R. Schloegl, M. Chamam, A. Wootsch, A.S. Canning, J.J. Gamman, S.D. Jackson, J. McGregor and L.F. Gladden, "Alkyne hydrogenation over Pd catalysts: A new paradigm". J. Catalysis 242, 26-37, 2006.
A.J. Sederman, M.D. Mantke, C.P. Dunckley, Z.Y. Huang and L.F. Gladden, "In situ MRI study of 1-octene isomerisation and hydrogenation within a trickle-bed reactor". Catal. Letts. 103, 1-8, 2005.
L.F. Gladden, "Magnetic Resonance: Ongoing and future role in chemical engineering research". AIChE Journal 49, 2-9, 2003.