Graphene oxide-nanobentonite composite sieves for enhanced desalination and dye removal

Recent research has focused on the synthesis and application of filtration sieves which facilitate fast solute separation during processes of desalination and wastewater treatment. This study reports a simple method for fabrication of Graphene oxide (GO)- nanobentonite (NB) filtration sieves with polyethylene glycol (PEG) interlinkage for efficient removal of mixed cationic dyes and electrolytes from their aqueous solutions. The GO-PEG-NB sieves were characterized for morphology, structural stability and vacuum filtration performance. Insertion of PEG linked NB particles between GO sheets was found to increase capillary size of the former and resist intercalation effects of cations present in effluent. Vacuum filtration processes carried out at moderate pressure (0.7 kg cm(-2)) had resulted in simultaneous removal of similar to 99% of 30 mg L-1 of ternary dyes and 40 g L-1 of mixed electrolytes with an optimum flux of 5.74 +/- 0.62 L-1 m(-2) h(-1). The GO-PEG-NB sieves offered good stability and efficient cation removal and therefore exhibited immense potential for treatment of wide scale real-time wastewaters.