Development of an Industrial Effluent Treatment Catalyst from Low Value Fleeces
This work is devoted to adding value to low value wool by the development of a solid phase oxidation catalyst supported on wool for the treatment of industrial wastewater. It is recognised that homogeneous systems have distinct disadvantages. They introduce metal cation pollutants into sewage, are not easy to replace, cannot be regenerated or used catalytically. As yet very few attempts have been made to develop a heterogeneous oxidation catalyst based on the hydrogen peroxide / Iron (III) system, and no attempts have been made using wool fibre as support. The few solid phase catalysts reported in the literature act by leaching iron (II) or (III) from the catalyst, whereupon catalysis takes place in the homogeneous phase. Immobilisation of a metal cation on wool fibre whilst still remaining catalytically active towards the decomposition of organic molecules in the absence of UV light is not trivial. It is crucially dependant on the nature of the immobilisation. Raw wool and scoured wools were investigated in their use as a wool catalyst. Modification regimes involving hydroxylamine and hydrazine combinations were evaluated. Both modified and unmodified wool samples were then impregnated with iron. Wool fibres were characterised physically and chemically for the various treatment regimes using a range of techniques including, Fibre Diameter Analysis, Tensile Strength, Scanning Electron Microscope, Energy Dispersive X-ray and Infra-red Spectroscopy. All wools treated were investigated for their catalytic activity against phenol. Static batch and dynamic studies were carried out to determine reproducibility between samples and catalyst lifetime. It was found that the Iron (III) wool catalyst in the presence of hydrogen peroxide and air was able to oxidise phenol rapidly. Catalytic activity and lifetime of the catalysts were improved with the use of an impregnation mixture of Iron with Calcium or Lithium Salts. iv Chromatographic techniques were used to determine the products formed throughout catalysis and confirm that phenol was oxidised according to the routes discussed in literature. Total Organic Carbon (TOC) studies were also conducted to investigate the reduction that could be achieved with the use of the wool catalyst. Finally, two effluents were provided containing phenolics in varying amounts and concentration by Chemtura and A H Marks. Static and dynamic evaluations were carried out to determine catalyst performance and longevity. Results were positive and showed potential in this area of effluent treatment. This was further supported by the wool catalyst’s ability to reduce TOC for both effluents.
- PhD