Abstract
M.Sc. (Chemistry)
Titania (TiO2) has been seen as one of the best semiconductor photocatalysts capable to photodegrade organic pollutants from water. This presents a method that textile industries can use to remove organic dyes from their effluents before release. The photocatalytic activity of TiO2 nanoparticles was conducted to also examine the influence of electron acceptors on the removal of dyes from water. The interaction between TiO2 nanoparticles and industrial dyes is inevitable because of the possible application of TiO2 in the removal of dyes in textile effluents.
Therefore, the possible application of TiO2 in the removal of dyes compels understanding the stability of TiO2 as influenced by industrial dyes and different abiotic factors. This is important for risk assessment purposes. The stability of TiO2 nanoparticles in the presence of disperse dye-stuff was conducted as influenced by pH, ionic strength and type of electrolyte. These parameters also influenced the physicochemical properties of the nanoparticles.
Understanding fate and behaviour of engineered nanomaterials (ENMs) in wastewater treatment plants (WWTPs) is important for the environmental risk assessment of ENMs. This is due to the appearance of ENMs in WWTPs that results from the wide spread application in consumer products and industrial applications. TiO2 has been reported as one of them. Thus, before environmental risk assessment can be conducted, studies at the points at which ENMs appear in high concentrations is important and WWTPs is one of them. Due to the in availability of nanoparticle test protocols, the Organisations of Economic Co-operation and Development (OECD) guidelines for testing of chemicals (303A) have been used by several researchers to study fate and behaviour of nanoparticles of interest. Therefore, the fate and behaviour of TiO2 nanoparticles was conducted following the OECD 303A. The findings of this study are summarised as follows:..