Cross-linked chitosan coated biodegradable porous electrospun membranes for the removal of synthetic dyes

Abstract

Abstract Chitosan crosslinked with 3-aminopropyltriethoxysilane was coated on porous poly (L-lactic acid) nanofibrous membrane to remove dyes from wastewater in the present study. The adsorption capacity of the composite membrane for the removal of methylene blue and rhodamine B was comprehensively studied. Large porous framework provided a high surface area to effectively immobilize the cross-linked chitosan on nanofibrous membranes. Batch trials were performed to evaluate the adsorption behaviour of membranes with variable crosslinking ratio, pH, initial concentration, temperature and time. Moreover, the adsorbent membranes before and after adsorption were characterized using scanning electron microscopy, x-ray energy dispersive analysis, and Fourier transform infrared spectrophotometer. Under optimum parameters, the adsorbent showed the removal capacity of 86.43 and 82.37\xa0mg/g for rhodamine B and methylene blue, respectively. Isothermal and kinetic experiments showed that Langmuir isotherm and pseudo second order kinetics correlated best with adsorption data. Finally, the mechanism of adsorption and reusability of membrane for five cycles was studied.