[1] Univ Free State, Dept Chem, POB 339, ZA-9300 Bloemfontein, South Africa
[2] Univ Maroua, Fac Sci, Dept Phys, POB 46, Maroua, Cameroon
[3] Univ Johannesburg, Dept Chem Sci, ZA-2028 Doornfontein, South Africa
[4] Nnamdi Azikiwe Univ, Dept Chem Engn, PMB 5025, Awka, Nigeria
[5] Kansas State Univ, Dept Chem Engn, Manhattan, KS USA
[6] North West Univ, Unit Environm Sci & Management, Water Res Grp, 11 Hoffman St, ZA-2520 Potchefstroom, South Africa
[7] Walter Sisulu Univ, Fac Sci Engn & Technol, Dept Appl Sci, Old King William Town Rd, Potsdam Site, ZA-5200 East London, South Africa
[8] Univ South Africa, Coll Sci Engn & Technol CSET, Florida Campus, ZA-1710 Johannesburg, South Africa
[9] Univ Nigeria, Dept Pure & Ind Chem, Nsukka, Nigeria
[10] Univ Nigeria, Fac Biol Sci, Dept Biochem, Nsukka, Enugu State, Nigeria
[11] Univ Nigeria, Sch Gen Studies, Nat Sci Unit, Nsukka, Enugu State, Nigeria
[12] Jiangsu Univ, Inst Environm Hlth & Ecol Secur, Sch Environm & Safety Engn, Zhenjiang 212013, Peoples R China
[13] Nelson Mandela Univ, Inst Coastal & Marine Res CMR, POB 77000, ZA-6031 Gqeberha, South Africa
[14] Masaryk Univ, Fac Sci, Res Ctr Tox Cpds Environm RECETOX, Kamenice 753-5, Brno 62500, Czech Republic