UJ Applied Chemistry professor talks nanotechnology for detection and removal of pollutants

Date: Oct 28, 2013 | News

Professorial Inauguration of Professor Catherine Ngila

Professor Catherine Ngila will deliver her inaugural address, titled “Metals everywhere, the good and the bad”, at the Council Chambers, Madibeng Building, Auckland Park Kingsway Campus on Tuesday, 29 October 2013 at 17:30.

​​Prof Ngila is currently the head of Applied Chemistry Department at the University of Johannesburg (UJ). Her analytical/environmental research work focuses on water pollution monitoring, developing analytical methodologies for detecting metal pollutants and other chemical substances including their speciation analysis, in water. She is currently investigating nanocomposite electrospun fiber sorbents and nanocomposite membranes for removal of pollutants in contaminated drinking water and wastewater effluents.

She received her bachelor of education in science, BEd(Sci) and MSc in Chemistry from Kenyatta University, Kenya in 1986 and 1992 respectively. She obtained her PhD from University of New South Wales, Sydney, Australia. Her teaching and research career began in 1989 when she was employed as a tutorial fellow at Kenyatta University and later promoted to lecturer in 1996 after obtaining her PhD degree. She has also worked at the University of Botswana as lecturer/senior lecturer (1998-2006), and at the University of KwaZulu Natal as senior lecturer (2006-2011) before joining UJ as a Professor of Analytical/Environmental Chemistry in April 2011.

Prof Ngila is a member of various chemical societies including American Chemical society Royal Society of Chemistry and South Africa Chemical Institute among other societies. She received awards from German Academic Exchange Service (DAAD) towards her MSc degree (1987-1989) and Equity and Merit Scholarship Scheme- Australian International Development Assistance Bureau for her PhD (1991-1995). She also received Kenyatta University Vice Chancellor research award (October 1997), University of Botswana Researcher award (2005); National Research Foundation (NRF) high resolution scanning electron microscopy equipment (2010), Water Research Commission (2012) among other awards.

Prof Ngila has authored and co-authored over 80 peer-reviewed research articles, review articles and book chapters, and has presented over 90 conference papers in different countries including the USA, UK, Switzerland, Australia, Turkey, South Africa, Swaziland, Botswana, Namibia, Tanzania, Kenya, Lesotho, Ghana, Senegal, among other countries. She has supervised over 50 Honours, MSc and PhD students including training of postdoctoral fellows. Currently, she has a research group of about 20 postgraduate students and postdoctoral fellows.

Abstract of the inaugural address by Catherine Ngila

Metals are prevalent in the environment. They are derived from both natural and anthropogenic sources. Certain metals are essential for plant growth and for animal and human health. However, if present in excessive concentrations they become toxic. Metals undergo an array of biogeochemical processes at reactive natural surfaces, including surfaces of clay minerals, metal oxides and oxyhydroxides, humic substances, plant roots, and microbes. These processes control the solubility, mobility, bioavailability, and toxicity of metals in the environment. The uses of metals vary widely from community to community. For instance metallic aluminium is used in the manufacturing of cookware. In form of sulphates, aluminium has been used for water treatment to remove colour and turbidity.

In addition to metals being essential for life, drinking water may contain metals which cause chronic or acute poisoning.

Interests in trace metals in water has grown markedly over the last decade particularly in the in search for highly sensitive methods of detecting the metals at trace levels. Equally important are the strategies to remove these metals from drinking water supplies at trace levels. Arsenic and chromium are two of the most toxic pollutants, introduced into natural waters from a variety of sources and causing various adverse effects on living bodies. In addition to metals as water pollutants, there are also organic and microbes.

With the introduction of nanotechnology in the last few years, scientists are frantically busy trying to come up with innovative ways of water purification which include metal nanoparticles for degrading organic substances as well as killing of microorganisms. One key approach to harness the application of nanotechnology lies in the development of analytical techniques to ‘see’ the pollutants in water and the environment, as well as strategies to remove them.​​​