Investigation of chromium preconcentration conditions by solid phase extraction method using activated carbon based ion-imprinted sorbent

Abstract

ABSTRACT In this study, chromium ion-imprinted (Cr-IAC) and nonimprinted activated carbon (Cr-NIAC) solid phases were synthesised using the surface ion imprinting method and used for the preconcentration of chromium ions. The characterisation processes of solid phases were performed by scanning electron microscopy/energy diffusion X-ray (SEM/EDX), Fourier transform infrared spectroscopy (FTIR), thermogravimetric (TG) analyses, and optimum preconcentration conditions were determined. For this purpose, the effects of parameters such as pH, type and concentration of the recovery solution, solution volume, flow rate on the chromium ion recovery efficiency were investigated and the capacity and selectivity properties of solid phases were determined. Metal ions were determined by a flame atomic absorption spectrophotometer. The adsorption isotherm was well fitted to the Langmuir isotherm model and the maximum adsorption capacity of the Cr-IAC and Cr-NIAC solid phases were found as 588.2 and 40.0 mg g−1 under the optimal experimental conditions. Preconcentration factor, limit of detection and limit of quantification were found as 10, 0.0340 μg mL−1, 0.102 μg mL−1 and 1.9%, respectively, and the relative standard deviation (RSD) was below 5%. In order to check the accuracy of the developed method, certified standard reference material and real sample analyses were performed with water samples and quantitative results were obtained.