Abstract
M.Sc. (Chemistry)
With the widespread use of nanoparticles, a concern has been raised to understand their behaviour in the actual environment. Monoclinic tungsten trioxide nanoparticles (m-WO3) have gained considerate interest as a photocatalyst particularly in the photodegradation of organic pollutants and oxidation of water resulting in the evolution of oxygen. As a result, the increased application will inherently lead to large amounts of m-WO3 being found in wastewater effluent. Wastewater effluent is a confluence of several chemicals; molecules such as natural organic matter, surfactants and amino acids to name a few. Natural organic matter present in wastewater include substances like humic acid and fulvic acid. Thus this study aimed to understand the fate and behaviour of m-WO3 nanoparticles in a wastewater treatment system. This research involved investigation of solution chemistry and its effects on the stability and aggregation kinetics of m-WO3. Thus, accurate characterization of the physicochemical properties was paramount as they could be extrapolated to their toxicological effects. The physicochemical properties measured included size distribution, aggregation/agglomeration, surface area, crystal structure, and surface charge...