Nanocomposite hydrogel based on layered double hydroxides (LDH)/ graphene oxide and nanocellulose whiskers for preconcentration and determination of Chromium (III) in environmental samples

Heavy metals are among the important and dangerous sources of environmental pollution [1]. The aim of this work was preparation and characterization of nanocomposite hydrogel based on layered double hydroxides (LDH)/ graphene oxide and nanocellulose whiskers and their use as an adsorbent for the preconcentration and determination of chromium(III) in water samples [2]. The synthesized hydrogel was characterized by SEM, FT-IR, XRD and EDX. A batch procedure was used to study the adsorption behavior of the synthesized hydrogel towards Cr3+ preconcentration by the solid phase extraction method.The effect of different parameters on the measurement and preconcentration efficiency of chromium (III) such as time of sonication, pH of sample, amount of adsorbent and sample volume were optimized by a central composite design (response surface) method and the effect of salt was studied by a one-at-a-time procedure. Under the optimized conditions, a recovery of % 100 a detection limit of 0.037 mg.L-1, an RSD of 2.8% (n = 6) and a preconcentration factor of 6.5 was obtained for the method. The proposed method was successfully applied to the determination of Cr(III) in real water sample.