Adsorption of cesium(I) using potassium zinc hexacyanoferrate and its application in simulated oilfield waterAuthor(s): Dandan Gao, Yaping Dong, Wu Li, Yahong Li
Potassium zinc hexacyanoferrate with the formula K2Zn3[Fe(CN)6]2 (KZnFc) was synthesized by a sol-gel method and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The adsorption performances of KZnFc to Cs+ in aqueous solution and simulated oilfield water were investigated. The effects of the various parameters like contact time, temperature, initial pH value of the solution, initial concentration of the cesium ion and other coexisting cations in the solution on the adsorption efficiencies of KZnFc have been studied systematically by batch experiments. Adsorption isotherm of KZnFc was studied and the fitted results indicated that the Langmuir model could well represent the adsorption process. Different thermodynamic parameters like Gibbs free energy, enthalpy and entropy of the adsorption process are also evaluated. The maximum adsorption capacity of Cs+ onto KZnFc was found to be 4.049 mmol g-1. About 96.13% of cesium in the simulated oilfield water could be absorbed by the synthesized KZnFc. This study will be helpful for understanding the adsorption mechanisms of cesium ion, and suggests that KZnFc could be used as potential adsorbent for adsorbing Cs+ from oil field water of Nanyishan.