Adsorption of Rose Bengal dye from waste water onto modified biomass

Abstract

The adsorption of rose Bengal dye (RB) from aqueous solution investigated in this work. Unmodified and modified nano orange peel has been praised for their extraordinary capacity to bind with dyes. Nano raw orange peel (OP) underwent carbonization to obtain nano orange peel activated carbon (AC). Nano activated carbon coated with nano chitosan (Cs) to obtain nano chitosan/activated carbon (AC/Cs) which decorated with carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) via polymer crosslinking method to create unique featured and the most effective composite (OP/AC/Cs/MWCNTs). These materials tested using FTIR, XRD, SEM and TEM. Herein, for nano raw orange peel and nano composite, batch experiments studied the effect of the RB dye initial concentration, pH of the medium, temperature. Furthermore, sorption isotherms, kinetics and thermodynamics were investigated. Additionally, thermodynamic calculations are made for parameters such as entropy (ΔS), enthalpy (ΔH), standard free energy (ΔG), sticking probability (S*) and activation energy (Ea). For the acquired data, Langmuir isotherm and pseudo-second order models were the preferred fitting. Also, the adsorption of rose Bengal dye is exothermic and spontaneous.