1. Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
2. College of Science, Engineering and Technology, Nanotechnology & Water Sustainability Research Unit, University of South Africa, Pretoria, South Africa
3. School of Industrial Engineering, Faculty of Engineering, North-West University, Potchefstroom, South Africa
4. Focus Area for Pure and Applied Analytics, Faculty of Natural And Agricultural Sciences, North-West University, Potchefstroom, South Africa