Removal of Congo Red from Aqueous Solution by Anion Exchange Membrane (EBTAC): Adsorption Kinetics and Themodynamics

Abstract

The adsorption behavior of anionic dye congo red (CR) from aqueous solutions using an anion exchange membrane (EBTAC) has been investigated at room temperature. The effect of several factors including contact time, membrane dosage, ionic strength and temperature were studied. Kinetic models, namely pseudo-first-order and pseudo-second-order, liquid film diffusion and Elovich models as well as Bangham and modified freundlich Equations, were employed to evaluate the experimental results. Parameters such as adsorption capacities, rate constant and related correlation coefficients for every model were calculated and discussed. The adsorption of CR on anion exchange membranes followed pseudo-second-order Kinetics. Thermodynamic parameters, namely changes in Gibbs free energy (∆G°), enthalpy (∆H°) and entropy (∆S°) were calculated for the adsorption of congo red, indicating an exothermic process.

Adsorption of Congo Red Dye from Aqueous Solutions by Montmorillonite as a Low-cost Adsorbent

“…Because of its high surface area and its high uptake capacity, activated carbon has been commonly used as an adsorbent for the removal of organic pollutants, but it is expensive and difficult to regenerate (Chen and Zhao 2009;Omidi-Khaniabadi et al 2015). In addition to activated carbon, some non-conventional adsorbents such as Aloe Vera leaves (Omidi-Khaniabadi et al 2016a), montmorillonite (Nourmoradi, Zabihollahi, and Pourzamani 2016a;Wang and Wang 2007), rice husk (Han et al 2008), bentonite (Bulut, Zacar, and Engil 2008), rice hull ash (Chou, Tsai, and Lo 2001), Azadirachta indica leaf (Bhattacharrya and Sharma 2004), Jujuba seeds (Reddy, Sivaramakrishna, and Reddy 2012), red mud (Tor and Cengeloglu 2006), polypyrrole-polyaniline nanofibres (Bhaumik, McCrindle, and Maity 2013), anion exchange membrane (Khan et al 2015), and ball-milled sugarcane bagasse (Zhang et al 2011) have been employed for the sorption of CR dye from aqueous media. Nowadays, there is an increasing interest for the use of low-cost sorbents for the removal of pollutants from wastewaters.…”

Development of cobalt-doped alumina hybrids for adsorption of textile effluents

“…It created more active site to cater more dye molecules on the surface. Doped alumina hybrid showed strong interaction towards Congo red (Khan et al, 2015) than methyl and basic fuchsine due to alteration of surface charge. It is observed that adsorption takes place through cation-cation exchange to replace with protonated amine, methyl and sodium ion Congo red >Basic Fuchsine > Methyl orange…”

“…The surface of adsorbents (alumina hybrids) without dopant is negatively charged due to presence of oxygen. It showed interaction with basic fuchsine (cationic nature) through cation-anion exchange (Khan et al, 2015;Santos and Boaventura, 2016) with the high adsorption removal while it showed weak interaction towards Congo red (anionic nature) Basic Fuchsine > Methyl orange > Congo red When dopant (cobalt) is doped onto alumina hybrids, nature of adsorbent surface is changed. It created more active site to cater more dye molecules on the surface.…”

Kinetics and Thermodynamics of Methyl Orange Uptake from Model Effluent by Watermelon Shells and Neem Leaves

“…It is a monoazo dye with the structure shown in Figure 1. A stock solution containing 1000 mg/L of the dye was prepared by accurately weighing 1.0 g of the dye solute into 1000-mL volumetric flask and dissolution to the graduated mark with de-ionized water [17]. All desired concentrations of calibrations and working standards were prepared by serial dilution for subsequent experiments.…”