1. Institute
for Water and Wastewater Technology, Durban University of Technology, Durban 4001, South Africa
2. Environmental
Engineering, Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India
3. Department
of Civil and Chemical Engineering, University of South Africa (UNISA), Pretoria 0002, South Africa
4. Environmental
Engineering and Science Program, Department of Biomedical, Chemical
and Environmental Engineering, University of Cincinnati, Cincinnati, Ohio 45220, United States
5. DST/CSIR
National
Centre for Nanostructured Materials, Council for Scientific and Industrial
Research, Pretoria 0001, South Africa