title: Application of banana peels nanosorbent for the removal of radioactive minerals from real mine water.
abstract: Transformation of agricultural waste such as banana peels into a valuable sorbent material has been proven effective and efficient in wastewater treatment. Further, transformation into nanosorbent to enhance the removal capacity of actinides (uranium and thorium) from synthetic and real mine water is extensively investigated in this study. The nanosorbent samples before and after adsorption were characterised by X-ray diffraction (XRD), Fourier transform infra-red (FTIR), zetasizer nanoseries and scanning electron microscopy (SEM) while the amount of radioactive substances adsorbed was determined by inductively coupled plasma optical emission spectroscopy. Results revealed that there was a crystallite size and particle size reduction from 108 to 12 nm and <65,000 nm to <25 nm respectively as a function of milling time. Furthermore, appearance and disappearance of nanofibers via milling was noticed during structural analysis. The functional groups responsible for the banana peels capability to coordinate and remove metal ions were identified at absorption bands of 1730 cm-1(carboxylic groups) and 889 cm-1(amine groups) via FTIR analysis. Equilibrium isotherm results demonstrated that the adsorption process was endothermic for both uranium and thorium. The Langmuir maximum adsorption capacity was 27.1 mg g-1, 34.13 mg g-1for uranium and 45.5 mg g-1, 10.10 mg g-1for thorium in synthetic and real mine water, respectively. The results obtained indicate that nanostructured banana peels is a potential adsorbent for the removal of radioactive substances from aqueous solution and also from real mine water. However, the choice of this sorbent material for any application depends on the composition of the effluent to be treated.
authors: Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, Pretoria, 0001, South Africa. Electronic address: atiba.opeyemi@gmail.com.
authors: Opeyemi A
authors: OA
authors: Oyewo
authors: Department of Chemical, Metallurgical and Materials Engineering, Tshwane University of Technology, Pretoria, 0001, South Africa.
authors: Maurice S
authors: MS
authors: Onyango
authors: SARChI Chair for Mine Water Management, Department of Environmental, Water, and Earth Sciences, Tshwane University of Technology, Pretoria, 0001, South Africa; Lappeenranta University of Technology, Laboratory of Green Chemistry, Sammonkatu 12, 50130, Mikkeli, Finland.
authors: Christian
authors: C
authors: Wolkersdorfer
mesh_terms: D000327:Adsorption; D008906:Mining; D028521:Musa; D013910:Thorium / Q000032:analysis; D014501:Uranium / Q000032:analysis; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D013910:Thorium; D014501:Uranium; D062065:Wastewater; D014875:Water Pollutants, Radioactive
keywords: Actinides; Adsorption; Banana peel; Mechanical milling; Nanostructure