Chitosan anchored nZVI bionanocomposites for treatment of textile wastewater: Optimization, mechanism, and phytotoxic assessment

Nisha Kumari; Sarita Arya; Monalisha Behera; Chandra Shekhar Seth; Ritu Singh

doi:10.1016/j.envres.2023.118041

Chitosan anchored nZVI bionanocomposites for treatment of textile wastewater: Optimization, mechanism, and phytotoxic assessment

Environ Res. 2024 Mar 15:245:118041. doi: 10.1016/j.envres.2023.118041. Epub 2023 Dec 30.

Authors

Nisha Kumari¹, Sarita Arya¹, Monalisha Behera¹, Chandra Shekhar Seth², Ritu Singh³

Affiliations

¹ Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Ajmer-305817, Rajasthan, India.
² Department of Botany, University of Delhi, Delhi 110007, India.
³ Department of Environmental Science, School of Earth Sciences, Central University of Rajasthan, Ajmer-305817, Rajasthan, India. Electronic address: ritu_ens@curaj.ac.in.

PMID: 38160973
DOI: 10.1016/j.envres.2023.118041

Abstract

In recent years, there has been a growing focus on treating textile wastewater due to its escalating threat to aquatic ecosystems and exposed communities. The present study investigates the adsorption efficacy of biopolymer functionalized nanoscale zero-valent iron (CS@nZVI) composite for the treatment of textile wastewater using the RSM-CCD model. The structure and morphology of CS@nZVI were characterized using XRD, FTIR, FESEM, and EDX. CS@nZVI was then evaluated for its adsorption potential in removing COD, color, and other physico-chemical parameters from textile wastewater. The results showed the high efficacy of CS@nZVI for COD and color removal from textile wastewater. Under optimal conditions (pH 6, contact time 60 min, and 1.84 g CS@nZVI), COD removal reached a maximum of 85.53%, and decolorization efficiency was found to be 89.73%. The coefficient of determination R² (0.98) and AIC (269.75) values suggested quadratic model as the best-fitted model for optimizing the process parameters for COD removal. Additionally, the physico-chemical parameters were found to be within permissible limits after treatment with CS@nZVI. The influence of coexisting ions on COD removal followed the order PO₄^3- > SO₄^2- > Cl^- >Na⁺ > Ca²⁺. The kinetics data fitted well with the pseudo-first-order reaction, indicating physisorption as the primary mechanism. The thermodynamic study revealed the endothermic nature of the removal process. Reusability tests demonstrated that great regeneration capacity of spent CS@nZVIafter five consecutive cycles. Furthermore, toxicological studies showed reduced toxicity in treated samples, leading to improved growth of Vigna radiata L. These findings suggest that CS@nZVI bionanocomposites could serve as an efficient, cost-effective, and eco-friendly remediation agent for the treatment of textile effluents, presenting significant prospects for commercial applications.

Keywords: Adsorption; Nanoscale zerovalent iron (nZVI); RSM-CCD; Reusability; Textile wastewater.

MeSH terms

Adsorption
Chitosan* / chemistry
Ecosystem
Textiles
Wastewater / toxicity
Water Pollutants, Chemical* / analysis

Substances

Wastewater
Chitosan
Water Pollutants, Chemical