Rhodamine B dye sequestration using Gmelina aborea leaf powder

Abstract

Chemically prepared activated carbon derived from Gmelina aborea leaves (GALAC) were used as adsorbent for the removal of Rhodamine B (Rh-B) dye from aqueous solutions. The adsorptive characteristics of activated carbon (AC) prepared from Gmelina aborea leaves (GAL) were studied using SEM, FTIR, pH point of zero charge (pH pzc) and Boehm Titration (BT) techniques respectively. The effects of pH, contact time, initial dye concentration and solution temperature were also examined. Experimental data were analyzed using four different isotherm models: Langmuir, Freundlich, Temkin and Dubinin-Radushkevich. Four adsorption kinetic models: Pseudo-first-order (PFO), Pseudo-second-order (PSO), Elovich and Intraparticle diffusion models to establish the kinetics of adsorption process. The RhB dye adsorption on GALAC was best described by Langmuir isotherm model with maximum monolayer coverage of 1000 mg g À1 and R 2 value of 0. 9999. The EDX analysis revealed that GALAC contained 82.81% by weight and 91.2% by atom of carbon contents which are requisites for high adsorption capacity. Adsorption kinetic data best fitted the PSO kinetic model. Thermodynamic parameters obtained for GALAC are (ΔG o ranged from-22.71 to-18.19 kJmol-1 ; ΔH o : 1.51 kJmol-1 ; and ΔS o : 0.39 kJmol-1 K À1 respectively) indicating that the RhB dye removal from aqueous solutions by GALAC was spontaneous and endothermic in nature. The cost analysis established that GALAC is approximately eleven times cheaper than CAC thereby providing a saving of 351.41USD/kg. Chemically treated GAL was found to be an effective absorbent for the removal of RhB dye from aqueous solution.

Economical and Eco-Friendly Adsorbent Derived from Coffee Waste for Efficient Adsorption of Methylene Blue: Characterization, Evaluation and Optimization Studies

“…In this study, the changes in the morphologies before and after adsorption process of MB dye by modified coffee ground wastes has been 5, which indicated the of adsorption process. Similar observation have also reported by the literatures [39,43,46,47].…”

“…Thus, the results of FTIR analysis indicated that the mechanism of MB dye bonding by the coffee waste powder was done. Similar observation was reported for green adsorbent derived from gmelina aborea leaf for sequestration of rhodamine B from aqueous solution [43]. However, the main active groups showed on the surface of adsorbent before and after adsorption process of methylene blue is presented in Table 2.…”

Bottom-up approach synthesis of core-shell nanoscale zerovalent iron (CS-nZVI): Physicochemical and spectroscopic characterization with Cu(II) ions adsorption application

“…The regression coefficient ( R 2 ) in pseudo second-order parameters are very close to unity and in some cases, it is exactly unity while in pseudo first-order, the R 2 values were very low across the concentrations. Previous studies carried out showed that the better the agreement between the q e , exp and q e , cal, the lower the values of these statistical tools, the better the model [7] , [40] . From the analysis of the statistical validity model, the low values of SSE, χ 2 and ∆q ( Table 6 ) further supported that pseudo second-order model best described the kinetic and mechanism of the adsorption process.…”

Two–three parameters isotherm modeling, kinetics with statistical validity, desorption and thermodynamic studies of adsorption of Cu(II) ions onto zerovalent iron nanoparticles

“…A typical batch adsorption study was carried out following procedure reported in our previous study 19 , 20 . 1000 ppm Cu 2+ stock solution was prepared by dissolving 2.5 g of CuSO 4 .5H 2 O in 1000 mL of distilled-deionized water.…”