1. Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
2. School of Materials Energy Water and Environmental Sciences, Nelson Mandela African Institution of Science and Technology, P.O. Box 447, Arusha, Tanzania
3. Department of Mechanical and Industrial Engineering, University of Dar es Salaam, P.O. Box 35131, Dar es Salaam, Tanzania
4. Faculty of Engineering and the Built Environment, Tshwane University of Technology, Private Bag X680, Pretoria 0001, South Africa