Professor Rob Brownd.r.brown@hud.ac.uk | 01484 473397
I graduated from the University of Birmingham with BSc(Hons) Chemistry in 1973, and the University of Leicester with a PhD in physical chemistry in 1977. I worked in industry for two years and then held teaching posts at Illinois State University and the University of Houston. I returned to the UK in 1987 and was Senior Lecturer/Principal Lecturer at Leeds Polytechnic before joining the University of Huddersfield in 1997.
I teach in areas across physical chemistry, and on the Science Foundation Year. My research interests are in catalysis, solid acids, solid bases and porous solids, biofuels, adsorption and calorimetry.
I am the Director of the Materials and Catalysis Research Centre in the Department of Chemical and Biological Sciences. Enquiries about the activities of the Centre and opportunities in it are very welcome. I have a number of administrative responsibilities, mainly to do with research and research student training, in the Department, in the School and more widely across the University.
Our main interests are in solid acid catalysts, particularly as replacements for homogeneous acid catalysts in liquid phase processes. We have published over sixty papers and review articles in this area.
Many liquid phase processes in fine chemical synthesis currently use homogeneous catalysts. While very effective, these catalysts are often difficult to separate from the reaction products and the separation processes result in a great deal of effluent. The use of solid catalysts in these reactions reduces this waste and reduces the environmental impact of the processes. The challenge is to design solid catalysts with activities high enough to justify their use as replacements for homogeneous catalysts.
We are working on solid acid catalysts as replacements for homogeneous acid catalysts AlCl3, H2SO4 etc. in Friedel-Crafts and other acid-catalysed reactions. Our interests are in: modified clay mineral catalysts, functionalised mesoporous molecular sieve materials, supported heteropolyacids, non-rigid acid catalysts (polymer-supported acids) and others.
Our interest is in the structure/function relationship in these materials, since improved understanding will lead to improved catalyst design. Since 1997 we have given increasing emphasis to the use of calorimetric adsorption techniques for the characterisation of catalytic materials and adsorbents in ways that can be used to predict their performance and so inform further development. Techniques in which probe molecules are adsorbed from the gas phase on dry catalyst, and from the liquid phase on solvated catalysts (isothermal titration calorimetry) have been developed and are now used routinely in our labs.
Over the past five years we have added calorimetric adsorption techniques based on flow systems. These allow us to study the kinetics as well as the thermodynamics of adsorption. They also permit the study of competitive adsorption so that catalysts can be studied under realistic conditions. The levels of detail available from these techniques on both the thermodynamics and the kinetics of catalyst adsorption processes are unique in the UK. We use the techniques to study materials prepared in our own labs as well as catalysts and adsorbents prepared by others, through an increasing number of collaborative projects with academic and industrial groups.
We welcome enquiries from those interested in our work.
Abuhabaya, A., Fieldhouse, J. and Brown, D. (2013) ‘Influence of production variables for biodiesel synthesis on yields and fuel properties, and optimization of production conditions’ Fuel , 103, pp. 963-969. ISSN 0016-2361
Brown, D. and Andrijanto , E. (2012) ‘New Microporous Polystyrene Sulfonic Acid Catalyst for Free Fatty Acid Esterification’. In: IEX 2012 The International Ion Exchange Conference, 19-21 September 2012, Queens' College, Cambridge
Ikhlaq, A., Brown, D. and Kasprzyk-Hordern, B. (2012) ‘Mechanisms of catalytic ozonation on alumina and zeolites in water: formation of hydroxyl radicals’ Applied Catalysis B: Environmental , 123/4, pp. 94-106. ISSN 09263373
Ikhlaq, A., Brown, D. and Kasprzyk-Hordern, B. (2012) ‘Mechanisms of catalytic ozonation: An investigation into superoxide ion radical and hydrogen peroxide formation during catalytic ozonation on alumina and zeolites in water’ Applied Catalysis B: Environmental , 123-4, pp. 94-106. ISSN 0926-3373
Cross, H., Parkes, G. and Brown, D. (2012) ‘Microwave calcination of Cu/Mg/Al hydrotalcite catalyst precursor’ Applied Catalysis A: General , 429/30, pp. 24-30. ISSN 0926860X
Nair, G., Adrijanto, E., Alsalme, A., Kozhevnikov, I., Cooke, D., Brown, D. and Shiju, N. (2012) ‘Glycerol utilization: solvent-free acetalisation over niobia catalysts’ Catalysis Science & Technology , 2 (6), pp. 1173-1179. ISSN 2044-4753
Andrijanto, E., Dawson, E. and Brown, D. (2012) ‘Hypercrosslinked polystyrene sulphonic acid catalysts for the esterification of free fatty acids in biodiesel synthesis’ Applied Catalysis B: Environmental , 115-6, pp. 261-268. ISSN 09263373
Shiju, N., Alberts, A., Khalid, S., Brown, D. and Rothenberg, G. (2011) ‘Mesoporous Silica with Site-Isolated Amine and Phosphotungstic Acid Groups: A Solid Catalyst with Tunable Antagonistic Functions for One-Pot Tandem Reactions’ Angewandte Chemie International Edition , 50 (41), pp. 9615-9619. ISSN 14337851
Shiju, N., Alberts, A., Khalid, S., Brown, D. and Rothenberg, G. (2011) ‘Mesoporous Silica with Site-Isolated Amine and Phosphotungstic Acid Groups: A Solid Catalyst with Tunable Antagonistic Functions for One-Pot Tandem Reactions’ Angewandte Chemie , 123 (41), pp. 9789-9793. ISSN 00448249
Abuhabaya, A., Fieldhouse, J. and Brown, D. (2011) ‘The Effects of Using Bio-diesel as Fuel on Compression Ignition (CI) Engine and Its Production from Vegetable Oils’. In: Proceedings of 2011 International Conference on Environmental, Biomedical and Biotechnology (IPCBEE). Singapore: International Association of Computer Science and Information Technoloyg (IACSIT). pp. 41-46. ISBN 978-981-08-9168-8
Raveendran Shiju, N., Yoshida, K., Boyes, E., Brown, D. and Gai, P. (2011) ‘Dynamic atomic scale in situ electron microscopy in the development of an efficient heterogeneous catalytic process for pharmaceutical NSAIDS’ Catalysis Science & Technology , 1 (3), pp. 413-425. ISSN 2044-4753
Abuhabaya, A., Fieldhouse, J. and Brown, D. (2010) ‘Evaluation of Properties and use of waste vegetable oil (WVO), pure vegetable oils and standard diesel as used in a compression ignition engine’. In: Future Technologies in Computing and Engineering Annual Researchers' Conference (CEARC'10). University of Huddersfield, Computing and Engineering Annual Researchers’ Conference 2010: The University of Huddersfield . pp. 71-76. ISBN 9781862180932
Cross, H. and Brown, D. (2010) ‘Entrained Sodium in Mixed Metal Oxide Catalysts Derived from Layered Double Hydroxides’ Catalysis Communications , 12 (3), pp. 243-245. ISSN 1566-7367
Shiju, N., Brown, D., Wilson, K. and Rothenberg, G. (2010) ‘Glycerol Valorization: Dehydration to Acrolein Over Silica-Supported Niobia Catalysts’ Topics in Catalysis , 53 (15-18), pp. 1217-1223. ISSN 1022-5528
Dacquin, J., Cross, H., Brown, D., Duren, T., Williams, J., Lee, A. and Wilson, K. (2010) ‘Interdependent lateral interactions, hydrophobicity and acid strength and their influence on the catalytic activity of nanoporous sulfonic acid silicas ’ Green Chemistry , 12 (8), pp. 1383-1391. ISSN 1463-9262
Abuhabaya, A., Fieldhouse, J. and Brown, D. (2010) ‘Variation of Engineering Performance and Emissions using Biodiesel Fuels’. In: 2nd International Conference on Nuclear and Renewable Energy Sources, 4th-7th July 2010, Ankara, Turkey , pp. 580-585
Montero, J., Brown, D., Gai, P., Lee, A. and Wilson, K. (2010) ‘In situ studies of structure–reactivity relations in biodiesel synthesis over nanocrystalline MgO’ Chemical Engineering Journal , 161 (3), pp. 332-339. ISSN 1385-8947
Bandyopadhyay, M., Shiju, N. and Brown, D. (2010) ‘MCM-48 as a support for sulfonic acid catalysts’ Catalysis Communications , 11 (7), pp. 660-664. ISSN 1566-7367
Yoshida, K., Shiju, N., Brown, D., Boyes, E. and Gai, P. (2010) ‘Double aberration-corrected TEM/STEM of tungstated zirconia nanocatalysts for the synthesis of paracetamol’ Journal of Physics: Conference Series , 241 (1), p. 012035. ISSN 1742-6596
Shiju, N., Williams, H. and Brown, D. (2009) ‘Cs exchanged phosphotungstic acid as an efficient catalyst for liquid-phase Beckmann rearrangement of oximes’ Applied Catalysis B: Environmental , 90 (3-4), pp. 451-457. ISSN 0926-3373
Siril, P., Shiju, N., Brown, D. and Wilson, K. (2009) ‘Optimising Catalytic Properties of Supported Sulfonic Acid Catalysts’ Applied Catalysis A General , 364 (1-2), pp. 95-100. ISSN 0926-860X
Pesaresi, L., Brown, D., Lee, A., Montero, J., Williams, H. and Wilson, K. (2009) ‘Cs-doped H4SiW12O40 catalysts for biodiesel applications’ Applied Catalysis A General , 360 (1), pp. 50-58. ISSN 0926-860X
Shiju, N., AnilKumar, M., Hoelderich, W. and Brown, D. (2009) ‘Tungstated Zirconia Catalysts for Liquid-Phase Beckmann Rearrangement of Cyclohexanone Oxime: Structure-Activity Relationship’ The Journal of Physical Chemistry C , 113 (18), pp. 7735-7742. ISSN 19327447
Brown, D. and Siril, P. (2008) ‘Enhanced Acidic and Catalytic Properties of Modified Polystyrene Sulfonic Acid Resins’. In: IEX 2008 Conference, 6-11 July 2008, Cambridge, UK , pp. 435-442
Kooli, F., Liu, Y., Alshahateet, S., Siril, P. and Brown, D. (2008) ‘Effect of pillared clays on the hydroisomerization of n-heptane ’ Catalysis Today , 131 (1-4), pp. 244-249. ISSN 0920-5861
Siril, P., Cross, H. and Brown, D. (2008) ‘New polystyrene sulfonic acid resin catalysts with enhanced acidic and catalytic properties ’ Journal of Molecular Catalysis A: Chemical , 279 (1), pp. 63-68. ISSN 1381-1169
Siril, P., Davison, A., Randhawa, J. and Brown, D. (2007) ‘Acid strengths and catalytic activities of sulfonic acid on polymeric and silica supports ’ Journal of Molecular Catalysis A: Chemical , 267 (1-2), pp. 72-78. ISSN 1381-1169
Narasimharao, K., Brown, D., Lee, A., Newman, A., Siril, P., Tavener, S. and Wilson, K. (2007) ‘Structure–activity relations in Cs-doped heteropolyacid catalysts for biodiesel production’ Journal of Catalysis , 248 (2), pp. 226-234. ISSN 00219517
Siril, P. and Brown, D. (2006) ‘Acid site accessibility in sulfonated polystyrene acid catalysts: Calorimetric study of NH3 adsorption from flowing gas stream ’ Journal of Molecular Catalysis A: Chemical , 252 (1-2), pp. 125-131. ISSN 1381-1169
Newman, A., Brown, D., Siril, P., Lee, A. and Wilson, K. (2006) ‘Structural studies of high dispersion H3PW12O40/SiO2 solid acid catalysts ’ Physical Chemistry Chemical Physics , 8, pp. 2893-2902. ISSN 1463-9076
Lapkin, A., Savill-Jowitt, C., Brown, D. and Edler, K. (2006) ‘Microcalorimetric Study of Ammonia Chemisorption on H3PW12O40 Supported onto Mesoporous Synthetic Carbons and SBA-15’ Langmuir , 22 (18), pp. 7664-7671. ISSN 0743-7463
Koujout, S. and Brown, D. (2005) ‘Calorimetric base adsorption and neutralisation studies of supported sulfonic acids’ Thermochimica Acta , 434 (1-2), pp. 158-164. ISSN 0040-6031
Felix, S., Savill-Jowitt, C. and Brown, D. (2005) ‘Base adsorption calorimetry for characterising surface acidity: a comparison between pulse flow and conventional “static” techniques ’ Thermochimica Acta , 433 (1-2), pp. 59-65. ISSN 0040-6031
Koujout, S. and Brown, D. (2004) ‘The influence of solvent on the acidity and activity of supported sulfonic acid catalysts ’ Catalysis Letters , 98 (4), pp. 195-202. ISSN 1572-879X
Hart, M. and Brown, D. (2004) ‘Surface acidities and catalytic activities of acid-activated clays’ Journal of Molecular Catalysis A Chemical , 212 (1-2), pp. 315-322. ISSN 13811169
Fesenko, E., Barnes, P., Parkes, G., Brown, D. and Naderi, M. (2003) ‘Application of SCTA to the study of the reactivity of acid-base catalysts’ Journal of Thermal Analysis and Calorimetry , 72 (3), pp. 1103-1105. ISSN 14182874
Fraile, J., Garcia, J., Mayoral, J., Salvatella, L., Vispe, E., Brown, D. and Fuller, G. (2003) ‘Experimental and theoretical studies on structure-reactivity relationships of titanium-modified silicas in the hydrogen peroxide-promoted oxidation of cyclohexene’ The Journal of Physical Chemistry B , 107 (2), pp. 519-526. ISSN 15206106
Koujout, S. and Brown, D. (2003) ‘Supported sulfonic acid catalysts in aqueous reactions’. In: Catalysis in Application. London, UK: Royal Society of Chemistry. pp. 178-185. ISBN 978-0-85404-608-9
Koujout, S., Kiernan, B., Brown, D., Edwards, H., Dale, J. and Plant, S. (2003) ‘The nature of the internal acid solutions in sulfonated poly(styrene-co-divinylbenzene) resins ’ Catalysis Letters , 85 (1-2), pp. 33-40. ISSN 1572-879X
Pickett, J., Naderi, M., Chinn, M. and Brown, D. (2002) ‘The adsorption and decomposition of cyanogen chloride by modified inorganic molecular sieves’ Separation Science and Technology , 37 (5), pp. 1079-1093. ISSN 0149-6395
Naderi, M., Pickett, J., Chinn, M. and Brown, D. (2002) ‘Modified mesoporous silicates for the adsorption and decomposition of toxic gases ’ Journal of Materials Chemistry , 12 (4), pp. 1086-1089. ISSN 1364-5501
Naderi, M., Dale, J., Parkes, G. and Brown, D. (2002) ‘Solvation of exchangeable cations in sulfonated polystyrene ion-exchange resins: an ESR study’ Reactive and Functional Polymers , 51 (1), p. 25. ISSN 1381-5148
Hart, M., Fuller, G., Brown, D., Dale, J. and Plant, S. (2001) ‘Sulfonated poly(styrene-co-divinylbenzene) ion-exchange resins: acidities and catalytic activities in aqueous reactions’ Journal of Molecular Catalysis A Chemical , 182-183 (1-2), pp. 439-445. ISSN 1381-1169
Edwards, H., Brown, D., Dale, J. and Plant, S. (2001) ‘Raman spectroscopic studies of acid dissociation in sulfonated polystyrene resins’ Journal of Molecular Structure , 595 (1-3), pp. 111-118. ISSN 00222860
Fraile, J., Garcia, J., Mayoral, J., Vispe, E., Brown, D. and Naderi, M. (2001) ‘Is MCM-41 really advantageous over amorphous silica? The case of grafted titanium epoxidation catalysts’ Chemical Communications (16), pp. 1510-1511. ISSN 1364-548X
Barnes, P., Fesenko, E., Parkes, G., Brown, D. and Naderi, M. (2001) ‘A new approach to the study of the reactivity of solid-acid catalysts: the application of constant rate thermal analysis to the desorption and surface reaction of isopropylamine from NaY and HY zeolites’ Journal of Physical Chemistry B , 105, pp. 6178-6185. ISSN 1089-5647
Michalik, J., Brown, D., Yu, J., Danilczuk, M., Kim, J. and Kevan, L. (2001) ‘Conduction electron paramagnetic resonance of metal nanoparticles in AlMCM-41 aluminosilica mesoporous molecular sieves’ Physical Chemistry Chemical Physics , 3 (9), pp. 1705-1709. ISSN 14639076
Hart, M., Fuller, G., Brown, D., Park, C., Keane, M., Dale, J., Fougret, C. and Cockman, R. (2001) ‘Acidities and catalytic activities of persulfonated poly(styrene-co-divinylbenzene) ion-exchange resins’ Catalysis Letters , 72 (3/4), pp. 135-141. ISSN 1011372X
Edwards, H., Brown, D., Dale, J. and Plant, S. (2000) ‘Raman spectroscopy of sulfonated polystyrene resins’ Vibrational Spectroscopy , 24 (2), pp. 213-222. ISSN 09242031
We will use siliceous ordered mesoporous molecular sieve materials and disordered silica gels as supports for acid catalysts. We will concentrate on supported sulfonic acids. We will prepare a range of these materials, using various supports and methods of functionalisation. Catalyst acidities will be characterised by adsorption calorimetry, and activity in a range of test reactions. The objective will be to identify the structural features in these materials which control catalytic activity and can be optimised to prepare catalysts for specific reactions.
The objective will be to study a range of solid base catalysts using adsorpion calorimetry with suitable acidic probe molecules, and to link the function of these materials to their basic properties and structures. Catalytic properties will be tested in model reactions. Initially, we plan to concentrate on layered double hydroxides and the mixed oxides which arise from their calcination. There are many variables to investigate in the composition and preparation of these catalysts and we hope to develop a model relating basic and catalytic properties to structural properties and synthetic routes/compositions.
Expanding clays such as montmorllinites will be characterised as the basis for acid catalysts. Materials will be characterised by base adsorption calorimetry and other spectroscopic techniques. We are particularly interested in incorporation of lanthanide metal ions with a view to generating strong Lewis acid catalysts, and these properties will be tested in suitable reactions. The objective is to develop an understanding of the way in which clay-based catalysts can deliver Lewis acidity and Lewis acid catalysis.
A range of basic catalysts will be charaterised by adsorption calorimetry and tested in the ester hydrolysis and transesterification reactions associated with the generations of biofuels from triglycerides. We will start with hydrotalcite materials and their calcination products, and move on to other mixed and single oxides. The objective will be to link structural properties to basicity and to activity in these reactions. It is hoped that this project will lead to collaboration within the Department over the application of the same catalysts to the degradation of lignin-type compounds, reactions with potentially greated importance than those of triglycerides.
