1. Eskom Power Plant Engineering Institute (EPPEI) Specialization Centre for Emission Control, School of Chemical and Minerals Engineering, Centre of Excellence in Carbon-based Fuels, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa
2. Department of Chemical and Metallurgical Engineering, Vaal University of Technology, Vanderbijlpark Campus, Private Bag X021, Vanderbijlpark 1900, South Africa