Biosorption of acid brown 14 dye to mandarin‑CO‑TETA derived from mandarin peels

Abstract

Several agronomic waste-materials are presently being widely used as bio-adsorbents for the treatment of toxic wastes such as dyes and heavy metals from industrial activities, which has resulted in critical global environmental issues. Therefore, there is a need to continue searching for more effective means of mitigating these industrial effluents. Synthetic aromatic dyes such as Acid Brown (AB14) dye are one such industrial effluent that is causing a serious global issue owing to the huge amount of these unsafe effluents released into the ecosystem daily as contaminants. Consequently, their confiscation from the environment is critical. Hence, in this study, Mandarin-CO-TETA (MCT) derived from mandarin peels was utilized for the removal of AB14 dyes. The synthesized biosorbent was subsequently characterized employing FTIR, TGA, BET, and SEM coupled with an EDX. The biosorption of this dye was observed to be pH-dependent, with the optimum removal of this dye being noticed at pH 1.5 and was ascribed to the electrostatic interaction between the positively charged sites on the biosorbent and the anionic AB14 dye. The biosorption process of AB14 dye was ideally described by employing the pseudo-second-order (PSO) and the Langmuir (LNR) models. The ideal biosorption capacity was calculated to be 416.67 mg/g and the biosorption process was indicative of monolayer sorption of AB14 dye to MCT biosorbent. Thus, the studied biosorbent can be employed as a low-cost activated biomass-based biosorbent for the treatment of AB14 dyes from industrial activities before they are further released into the environment, thus mitigating environmental contamination.