Porous composite CMC–KCuFC–PEG spheres for efficient cesium removal from wastewater

Abstract

In this work, a highly stable porous composite CMC–KCuFC–PEG was prepared via the cross-linking reaction of biodegradable carboxymethyl cellulose sodium (CMC) and potassium copper ferrocyanide (KCuFC) using polyethylene glycol 6000 (PEG6000) as a porogen for ¹³⁷Cs removal from wastewater. The adsorption conditions including pH value, adsorbent dosage, contact time, initial Cs⁺ concentration, temperature and competitive ions were systematically investigated, and the results demonstrated that this CMC–KCuFC–PEG was effective and stable in wastewater with a wide pH range (2–10) or NH₄⁺. The maximum adsorption capacity of Cs⁺ was up to 149.8 mg g⁻¹. Moreover, adsorption kinetic and adsorption isotherm studies showed that the adsorption process of CMC–KCuFC–PEG was well-fitted by the linear pseudo-second-order kinetic and Freundlich models, respectively. All the results suggest that CMC–KCuFC–PEG exhibits potential application for cesium removal from wastewater.