Nanotechnology – a revolutionary water treatment solution
Nanotechnology is among the most revolutionary technologies in human history. For example, nanotechnology-driven capabilities have dramatically revolutionised the way doctors treat their patients, the way clean energy is generated, how contaminated environmental ecosystems can be remediated, and how very clean water will likely be provided in the most remote rural and semi-urban human settings. “These applications, among others, have great relevance to South Africa, particularly in terms of addressing some of the Government’s Grand Challenges such as poverty alleviation, rural development, health and sanitation, etc.” says Dr Ndeke Musee, CSIR.
A common problem in developing countries is drinking water that is contaminated with bacteria and viruses, which are the main cause of water-borne diseases. Through scientific research a need for the development of technologies for water disinfection and microbial control has emerged. According to Dr Marelize Botes, University of Stellenbosch, the reliability of chemical disinfectants and membrane-based water filtration systems employed to control microbial pathogens is still under question. “The formation of harmful disinfection by-products and biofouling of water filtration membranes are major problems” says Dr Botes. Another concern is the poor maintenance of water distribution networks that decreases drinking water quality. Therefore an urgent need exists for decentralised and point-of-use water treatment and reuse systems.
The use of nanofibres, such as those fabricated by electrospinning, offers one potential solution for the present obstacles to reliable water treatment. The small pore size, high specific surface area and high porosity of electrospun nanofibre webs can be utilised to separate solid impurities from the liquid phase through filtration, ensuring good quality drinking water. According to Dr Botes the electrospun nanofibres could play an important role in resolving or ameliorating many of the problems involved in water purification and treated water quality.
The published literature indicates that there are risks associated with nanomaterials as they are sometimes toxic to humans and the wider environment because of their inherent physicochemical properties. However, the same properties render them novel for a wide range of applications. “As for now, the social, economic and environmental benefits of nanotechnology are beyond debate, therefore, the technology’s potential risks and merits need to be managed effectively to protect both humans and environment” says Dr Ndeke. The understanding of risks at the infancy stage and the proactive approach towards managing such risks becomes critical.
The water sector can apply nanotechnology to develop more cost-effective and high-performance water treatment systems, as well as instant and continuous ways to monitor water quality, among others. Nanotechnology is a multi-disciplinary research and development area, bringing together chemists, physicists, biotechnologists and engineers to work towards improving water quality.
South Africa has taken a leading role within the Southern African Development Community with the development of the two Nanotechnology Innovation Centres (NICs) that were launched at the CSIR and Mintek in 2006/07. The Water and Health Research Group at the University of Johannesburg has been investigating nanotechnology for water treatment since 2002. The South African Government also developed the National Nanotechnology Strategy, which was launched in April 2006, following the explosive interest shown by the international community in this water treatment technology.
Nanotechnology shows much potential to solve water quality challenges within the water sector and research efforts in this field could serve to ameliorate many of South Africa’s water problems.
For more information please see the presentations made during the WRC's nanotechnology media breakfast workshop:
Nanotechnology:understanding potential risks and the adoption of proactive paradigm
The applications of nanofibers in water treatment
The application of of nanotechnology in drinking water treatment
For further information contact:
Dr Jo Burgess
Tel: 012 330 9039
job@wrc.org.za