A Green Approach for Micro Determination of Silver(I) in Water and Soil Samples Using Vitamin C

A cloud point extraction/solvation method (CPE-SM) based on the use of vitamin C as a chelating agent was developed for the separation and determination of silver in environmental samples. TritonX-۱۰۰ was used to extract silver ions in aqueous solutions after forming solvation species with vitamin C in the presence of salting-out (۰.۵ mol L-۱ KNO۳) at ۹۰ ̊C for ۱۰ minutes. This study evaluated the main parameters affecting the CPE-SM method, such as the kind and concentration of the salting-out, organic reagents, silver ion, temperature, heating time, and volume of surfactant. Under the optimized experimental factors, the calibration curve was linear in the range (۰.۱ -۱۰ μg/L). The relative standard deviation (RSD) was ۱.۱-۲.۹% for n:۵ at ۱,۴,۹ μg L-۱, a low limit of detection (LOD), and a limit of quantification (LOQ) of ۰.۰۳۵, ۰.۱۱۶ μg L-۱ respectively. The accuracy of the method was evaluated by two independent techniques (flame atomic absorption spectrometry – FAAS, and spectrophotometry - using dithizone as a complexing agent). The CPE-SM technique was used to preconcentrate and determine the silver ions in river water, tap water, and soil samples, and the results were favorable and good.

Keywords:

Cloud point extraction , Silver , Solvation method , Solvent extraction , Vitamin C