A Study On Cloud Point Extraction For Determination Of Trace Chromium In Environment By Spectrophotometry And The Recovery Method Of The Extraction Agent

A new cloud point extraction (CPE) technique was developed for the separation and enrichment of trace chromium in samples by no poisonous and no evaporable extracting agent and determination by small examine instrument with spectrophotometry. The method is based on the property of no-ion surfactant Triton X-114 that is when heating it to the cloud point, it will become to two phases. the hydrophobic colored chelate complex formed by Cr(Ⅵ) and diphenylcarbazide moved into the surfactant rich phase, thus the separation and enrichment of the Cr(Ⅵ) was realized. Then the spectrophotometry can be used to determine the content of Cr(Ⅵ). The study on the condition of separation and enrichment was performed detailedly, the regression equation of it was established, the detection limit of Cr(Ⅵ) ion is 1.5μg/L with RSD of 2.40%. For surface water, sewage and soil samples, the chromium recovery of standard addition of the method was 95.57%-102.33%, this method can meet the environment detection requirement and is suitable for accurate determation of Cr(Ⅲ). The recircle method for Triton X-114 reuse was generated...