Abstract
The scarcity of water is a serious global problem. Due to contamination, clean water sources are threatened on daily basis and the provision of safe and affordable water to the needs of people is becoming an impossible. Major water pollutants can be divided into pathogens and chemicals. The scarce fresh water available in South Africa is declining in quality due to destruction of river catchments and increase in pollution caused by urbanisation, energy use, damming of rivers, mining, deforestation, agriculture, wetlands destruction, industrialisation, and accidental water pollution. About 2% of totally produced dyes are released into the water systems as effluents. These dyes are capable of causing allergic dermatitis, cancer, skin irritation, and mutation. They are also teratogenic and poisonous to fish species, people, and microorganisms.
. The PVDF/GO(Cu-tpa) composite membranes of different MOF concentration and wt% were prepared via phase inversion and characterised with FTIR, AFM, and SEM including surface morphology, cross sectional view, EDS and elemental mapping and their performance were tested on WCA, water uptake, pure water flux and decolourisation of dye at different concentrations. The synthesis of GO was achieved by modified Hammer’s method and the GO was used with Cu-tpa to synthesise the composite. PVDF was used as the base polymer, PVP as a pore forming agent, and NMP as a solvent in preparation of membranes containing different fillers. The functional groups within the membrane were analysed by FTIR, AFM was used for topography and roughness, WCA was used to investigate the hydrophilicity, the information about the adsorption capacity of membranes was achieved via water uptake experiments, and membrane flux was utilised to obtain the information about the permeation of the membrane towards pure water. SEM was used for for the analyses of cross sectional area, surface morphology, EDS and EDS elemental analysis. Two membranes out of six were found to have morphological defects due to systematic and random errors. In WCA, pure water flux, and water uptake, the PVDF membrane was found to be hydrophobic and PVDF/[GO(Cu-tpa)0.1]0.25 membrane was found to be hydrophilic, and for decolourisation of the dye, hydrophobic membranes performed better than hydrophilic membranes.
M.Sc. (Nanoscience)