Synthesis and characterization of nanocomposites containing Buchholzia coriacea pod decorated with multi-walled carbon nanotubes for remediation of rhodamine B dye from aqueous solution

Abstract

AbstractA novel nanocomposite (WKM) was synthesized by crosslinking Buchholzia coriacea pod (WK) and f-MWCNTs for the efficient adsorption of rhodamine B (RhB) from wastewater. The uptake of RhB onto WK and WKM was influenced by initial pH, adsorbent dose, the temperature of the adsorptive system, contact time and initial RhB concentration. Optimum experimental conditions of 100 min agitation time, 0.05 g dosage, solution pH 3.0 and 100 mg dm−3 initial concentration were obtained. The uptake of RhB onto WK and WKM was well expressed by Freundlich isotherm and a monolayer maximum uptake capacity of 67.82 mg g−1 and 87.58 mg g−1 was determined for WK and WKM, respectively. The adsorption of RhB onto WKM and WK followed the Elovich and pseudo-first-order kinetic models, respectively. Thermodynamic parameters such as ∆G°, ∆H° and ∆S° reveal that the uptake of RhB onto WK and WKM was spontaneous and endothermic. Meanwhile, WKM demonstrated excellent reusability. Hence, this study presents a nanocomposite (WKM) with robust potential for RhB removal.