Abstract
A simple and effective method is presented for extractive preconcentration of uranium(VI) in water, in which the ionic liquid, 1-octyl-3-methylimidazolium hexafluorophosphate, abbreviated as [C8mim][PF6], was used as novel medium for liquid/liquid extraction of uranium(VI) and new reagent, dimethylphenylazosalicylfluorone, abbreviated as DMPASF, was employed to form neutral uranium(VI)-DMPASF complex. DMPASF reacted with uranium(VI) rapidly to form a stable red complex, the complex was then extracted into [C8mim][PF6] phase, and the uranium(VI) in [C8mim][PF6] was back-extracted into aqueous phase again with 3.0 mol L−1 hydrochloric acid. The extraction efficiency, back-extraction efficiency and preconcentration factor were 98.9%, 96.5% and 200 times for 100 µg of standard uranium(VI) in 1000 mL of water samples, respectively. The preconcentration coupled with spectrophotometry with chlorophosphonazo III, abbreviated as CPAIII, was developed for determination of ultra trace uranium(VI) in natural water. The apparent molar absorptivity of the uranium(VI)-CPAIII complex and the detection limit which was calculated using three times the standard error of estimate of the calibration graph was found to be 3.17 × 106 l mol−1 cm−1 and 0.22 ng mL−1 of uranium(VI), respectively. The absorbance of the uranium(VI)-CPAIII complex at 670 nm increase linearly with the concentration of uranium(VI) up to 45 µg of uranium(VI) in 1000 mL of aqueous solution. The interference study show that the determination of uranium(VI) is free from interferences of almost all positive and negative ions found in water samples. The relative standard deviation (N = 10) was 1.3% for uranium for 10 replicate determinations in the solution containing 1.0 µg L−1 of uranium(VI). The proposed method has been successively applied to determination of ultra traces of uranium(VI) in seawater samples.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Environmental Analytical Chemistry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
