Thermodynamic and Isothermal Studies of Congo RedAdsorption onto Modified Bentonite

Abstract

− Adsorption of Congo Red (CR) from dye-containing effluents using modified bentonite (MB) has been investigated here. Isothermal studies were conducted to ascertain maximum adsorption capacity of the adsorbent. MB exhibited superior adsorption capacity compared to other low-cost adsorbents. Experimental data fitted the Langmuir isotherm better, indicating monolayer coverage of CR on MB. The feasibility of the process was measured in terms of separation factor R L . The values of Gibbs free energy, entropy and enthalpy were calculated from the thermodynamics of the process. Adsorption was feasible and spontaneous, being endothermic. Analytical techniques including SEM, EDS, FTIR and XRD were applied to characterize MB and also to provide conclusive proof of the accumulation of CR on to MB.

Integrating rod‐shaped nickel molybdate@polypyrrole matrix for sustainable adsorptive removal of organic dye: Kinetics, isotherm, and thermodynamics study

“…The utilization of the adsorption technique for removing organic dyes from water sources is highly cost‐effective, and the reusability of the composite for multiple cycles makes it a better, economical, and environmentally friendly candidate for removing pollutants from water sources. The synthesized PPy/NiMoO 4 has higher adsorptive capacity toward MB dye than other composites like PPy macro nanoparticles, 28 activated carbon, 29 silica nanosheets, 30 and graphene oxide/chitosan, 31 reported for the removal of MB dye from the water bodies. The efficacy of the synthesized composite makes it a better adsorbent for the water remediation process.…”