Abstract
The quality of drinking water sources in a rural settlement within the Chief Albert
Luthuli Local Municipality in Mpumalanga, South Africa was studied over a period of
8 months (from June 2014 – February 2015). Specifically the community that was
used as a case study in this project is Lochiel, which has approximately 5000
residents. The community has no supply of purified water. It relies on open wells and
boreholes as direct sources of drinking water and water for domestic purposes. At
the inception of the study, no existing information could be found on the quality of
these drinking water sources. The quality of these water sources was studied by
determining the levels of toxic metals, organics, and bacteria using a range of
analytical methods. The results obtained showed that the quality of the drinking
water was generally acceptable and differed for each source and with change in
seasons of the year. However, the study revealed that the concentrations of Co, Pb,
Mn, Fe, chlorophenols, nitrophenols, E. coli and total coliforms were higher than the
acceptable limits in some of the sources.
In an attempt to develop materials to remove the detected pollutants in the water
sources, antibacterial nanofibres based on chitosan (CS) and β-cyclodextrins (β-
CDs) were synthesized for use in a point-of-use (POU) system. The CS and -CDs
polymer powders were chosen due to their remarkable properties such as
biodegradability, biocompatibility, low toxicity, gratifying design flexibility and cost
effectiveness. The polymer powders were fabricated in the form of nanofibres using
an electrospinning technique. Their ability to be electrospun was enhanced by the
addition of other polymers prior to the preparation of the electrospinning solutions.
Polyacrylamide (PAA), polyethylene glycol (PEG) and polyisoprene (PIP) were
blended with CS to prevent its stream break-up, reduce its surface tension, improve
its entanglement during electrospinning (polymers with high molecular weight assist
in formation and entanglement of the jet, thereby resulting in fibre formation) and to
reduce the swelling capacity of the synthesized nanofibres. Uniform non-beaded CS
based nanofibres were obtained by electrospinning a CS polymer solution containing
CS:PAA = 3.5:1, 5% PEG and 80% PIP relative to the CS. The optimum
electrospinning conditions for the CS based nanofibres were: injection flow rate of
0.7 mL·h-1, a distance of 22 cm between the tip of the needle and the collector and a...
M.Sc. (Chemistry)