Characterization and deployment of surface-engineered chitosan-triethylenetetramine nanocomposite hybrid nano-adsorbent for divalent cations decontamination

Abstract

The latency of toxic cations in the ecosystem poses serious ecological problems due to its bioaccumulation potential and toxicity to living organisms. The effective removal of these wastewater cations releasing from multi-industries is a bottleneck issue. Therefore, an attempt has been made to design a suitable sorbent for cations sorption from the aqueous environment. The chitosan biopolymer was modified with triethylenetetramine to incorporate active sites in the polymeric sequence to boost up its cations sorption capacity. Triethylenetetramine molecule anchoring chitosan (CH-TET) was authenticated through elemental assay, Fourier-transform infrared spectroscopy and 13C NMR in solid-state, scanning electron microscopy and thermal analysis. The sorption of lead (1.94 mmol g−1), copper (2.79 mmol g−1) and nickel (1.53 mmol g−1) was carried out using the functionalized chitosan from aqueous solution, which showed higher sorption capacity for lead and copper than the pristine chitosan in terms of Langmuir sorption isotherm. To scrutinize the mechanism of sorption and energy of interaction between sorbent and sorbate, Langmuir, Temkin, and Freundlich isotherm models were used for sorption study. The Langmuir model showed the best fitting to the results based on lower error function values and a higher correlation coefficient (R2). It can be concluded that the triethylenetetramine-modified chitosan might be considered as an effective sorbent for cations removal from industrial wastewater.