Reaction Engineering and Catalytic Technology (REaCT)
REaCT’s research, involving chemistry and materials science as well as chemical engineering, aims to conceive, design, model, characterise, control and optimise catalysts, reactors and processes for chemical and fuel synthesis, energy conversion and for treating effluents, wastes and spent catalysts. Current activities include:
Catalyst technology
The overall performance of an industrial catalyst depends not only on the activity of the catalytic component, but also on the micro and macro structure of the porous carrier, in which the active component is immobilised. Computational methods and rapid prototyping techniques are being developed for rational design of porous catalyst supports, so the full potential of a catalyst can be realised, by optimising its mass and heat transfer characteristics.
Combined reaction and separation
Combining reaction and separation in a single unit operation has advantages for achieving enhanced conversions and yields in catalysed reversible reactions. Selective absorption, adsorption and permeation, with reaction are all being investigated, as are imposed thermal effects (endothermic-exothermic coupling). Current projects involve pressure swing reactors, rapid pressure swing reactor operation (RPSR), temperature - cycled adsorptive reactor (TCAR), and liquid multiphase reactor systems.
Electrochemical engineering
Electrochemical engineering involves the conception, design, construction, characterisation, modelling, control and optimisation of electrochemical processes, to convert electrical into chemical energy (electrolysis - Cl2 + NaOH, adiponitrile, Al, Zn, etc.), and vice versa (batteries and fuel cells). Electrode reactions enable oxidations and reductions to be carried out under mild conditions, enable reagent recycling and, when well designed, produce no wastes or effluents. Hence, novel electrochemical reactors and processes, utilising both oxidations and reductions, are being developed, e.g. for recovering heavy metals from aqueous effluents, wastes, such as end-of-life electrical and electronic equipment (WEEE), and from spent precious metal-containing catalysts.
Environmental catalysis
Catalytic processes are being developed for treatment of industrial effluents, abatement of NOx emissions from diesel and lean burn engines, and for utilising carbon dioxide, both as solvent and reactant.
Fine chemical synthesis
In liquid multiphase catalysis, the catalyst is dissolved in one of several immiscible liquid phases, while the reactants and products are in the remaining phases. The most common configuration is biphasic, using two immiscible liquids, usually a water - soluble catalyst in an aqueous phase, in contact with an organic phase. Liquid multiphase catalysis offers the advantages of homogeneous catalysis, namely atom efficiency and good control of selectivity, with the ease of catalyst separation and recycle associated with heterogeneous catalysts. This approach is being applied to several processes of importance in the fine chemicals industry. Other projects involve immobilised homogeneous catalysts, and catalytic processes for selective hydrogenation.
Fuel Cells
Intermediate temperature (500 - 700 C) solid oxide fuel cells (SOFCs) are the subject of research projects and are being developed commercially by a College spin-out company (Ceres Power Ltd. ). Autothermal, internal reforming of natural gas is also being studied for application in SOFCs.
Modelling of catalytic processes
The synthesis of highly selective novel catalysts and the design of efficient catalytic processes require modelling of hydrodynamic, thermodynamic and kinetic factors of both catalyst and reactor design. Computational tools, integrating molecular aspects of catalyst surface chemistry, transport processes and reactor hydrodynamics, are being developed for simulating catalytic processes. The application of such tools has led to the design of new three - way automotive catalysts and selective hydrocarbon hydrogenation catalysts.
Refinery and synthesis gas processes
In improved understanding of catalyst deact ivation and stripping in fluid bed catalytic cracking of hydrocarbons, is being sought to provide the basis for predictive models. Catalytic hydrotreating, especially deep hydrodesulfurisation, is being studied for production of clean diesel fuels. The syntheses of methanol, oxygenates, fuels and other hydrocarbons from synthesis gas, are being developed for remote natural gas conversion and carbon dioxide utilisation; e.g. the synthesis of dimethyl ether, which combines a reversible reaction (methanol synthesis) with an irreversible reaction (methanol dehydration), in a single reactor.
Structured reactors
Structured catalytic reactors, such as catalytic monoliths in gas - liquid - solid reactors and membrane reactors, are being developed for liquid phase hydrogenation, selective oxidation, and for small scale hydrogen peroxide production. Membrane reactors are being developed, especially for methane and natural gas conversion processes
Dr Klaus Hellgardt
Co-ordinator
