Advanced Materials and Porous Solids
Advances in chemical engineering and the need to improve process rates and efficiency are stimulating the need to produce and characterise novel materials, and the Department is making important contributions in a number of areas.
We are particularly prominent in the development of special carbon structures and porous oxides and structured adsorbents, which are used for:
- Hydrogen storage and oxidation in fuel cells
- Catalyst supports in reaction engineering
- Gas separations in aggressive environments
- Novel membranes for electrochemical and environmental separation processes.
The need to achieve a high reaction surface area and high catalytic activity has stimulated the Department's novel work on the engineering of surfaces, not just on a microscopic scale but also on a molecular one.
As an example, nanostructures of carbon can be produced in tubular form and are being considered as hydrogen storage media. Gas can be stored in central cavities of the tubes and in the interstitial spaces between tube arrays.
Modelling studies show optimum configurations of tubes for maximum hydrogen adsorption and work is underway to test how far practical structures can approach these optimum predictions.
A variety of novel membrane materials are being made and characterised within the Department.
We put particular emphasis on understanding the relationship between membrane properties (shape, porosity, area and mass transport) and their separation efficiency, and a number of promising avenues are being explored.
Annular hollow fibre membranes containing immobilised enzymes are being studied for glucose fermentation. Solid oxide membranes are used for methane coupling reactions and combined electric and pressure fields are being modelled for the separation of carbon dioxide and hydrogen sulphide gases.
Dissolved oxygen is being removed from ultra pure water for applications in the semiconductor industry.
Microporous solids are used in catalysis, gas separation, soil remediation, water management, hydrothermal vents, oil recovery and the removal of metal and organic contaminants from process streams.
We are making and testing novel monolithic structures for environmental control where their pressure drop characteristics outperform more traditional materials. We have developed the world's fastest thermal swing adsorption process. We are correlating fundamental structure and transport in porous solids with their performance.
We are using a combination of traditional techniques (gas sorption, porosimetry and electron microscopy imaging) with methods such as magnetic resonance imaging (MRI), and nuclear magnetic resonance spectroscopy (NMR). This will contribute towards improvements in catalysts, which will be designed to have more uniform reaction distribution and be more resistant to deactivation.
A further example is in the area of enhanced oil recovery, where a better characterisation of the internal void space of porous oil-bearing rocks leads to improvements in the amount of oil recovered. High throughput experimentation is being developed for rapid screening of heterogeneous catalysts.