1. Department of Chemical Engineering, School of Engineering, College of Science, Engineering, and Technology (CSET), University of South Africa, Florida Campus, Johannesburg 1709, South Africa
2. Department of Civil, Architecture and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125 Naples, Italy
3. Department of Chemical Engineering, Faculty of Engineering and the Built Environment, Durban University of Technology, Steve Biko Campus, Musgrave Durban 4001, South Africa