Functionalised mesoporous biosorbents for efficient removal of hazardous pollutants from water environment

Abstract

Wastewater from industrial complexes contains a significant amount of non-biodegradable azo dyes that present a hazard to animals, plant life and humans. The sorbents from biomass are showing a promising potential for the removal of azo dyes through biosorption. Hence, this research presents the capability of using pomegranate peel (Punica granatum) as a novel biosorbent for the uptake of azo dye Eriochrome Black T (EBT) from an aqueous solution. The effective removal of EBT was monitored by adjusting sorption parameters including pH value, mass of the biosorbent, EBT concentration and consecutively studying the sorption kinetics. The samples of biomass were analysed by various instrumental techniques and physio-chemical methods. After sorption experiments concentration of Eriochrome Black T was analysed by UV–Vis spectrophotometer. The removal of EBT was found to be optimal at the pH value of 3 with 100 mg of biosorbent by EBT concentration of 150 mg/L during a contact time of 90 min at room temperature. Under these conditions, the adsorption capacity was determined as 46.10 mg/g. By examining the adsorption kinetics, it was found that biosorption takes place through a combination of different mechanisms from which the pseudo-second-order model (r2 = 0.99), takes up the major role. The values of the correlation coefficients for the investigated models of isotherms show the best agreement with Langmuir's (r2 = 0.97) and Temkin's (r2 = 0.92) models. The novel data of cost evaluation classifies pomegranate peel as a low-cost adsorbent with promising potential for the removal of investigated azo dye, while the adsorption process is economically feasible (0.034$ for the uptake of 1 g dye molecule) paving the way for new biotechnological advances in wastewater decontamination.