Developing a New Micro Cloud Point Extraction Method for Simultaneous Preconcentration and Spectrophotometric Determination of Uranium and Vanadium in Brine

Abstract

A fast, simple, and economical method was developed for simultaneous spectrophotometric determination of uranium(VI) and vanadium(V) in water samples based on micro cloud point extraction (MCPE) at room temperature. This is the first report on the simultaneous extraction and determination of U(VI) and V(V). In this method, Triton X114 was employed as a non-ionic surfactant for the cloud point procedure and 4-(2-pyridylazo) resorcinol (PAR) was used as the chelating agent for both analytes. To reach the cloud point at room temperature, the MCPE procedure was carried out in brine. The factors influencing the extraction efficiency were investigated and optimized. Under the optimized condition, the linear calibration curve was found to be in the concentration range between100 -750 and 50 -600 μg L -1 for U(VI) and V(V), respectively, with a limit of detection of 17.03 μg L -1 (U) and 5.51 μg L -1 (V). Total analysis time including microextraction was less than 5 min.

Preconcentration and Determination of Trace Vanadium(V) in Beverages by Combination of Ultrasound Assisted-cloud Point Extraction with Spectrophotometry

“…In general, the most commonly used analyti-cal techniques are flame atomic absorption spectrometry (FAAS), 10,11,12 electrothermal atomic absorption spectrometry (ET-AAS), which is also known as graphite furnace AAS (GF-AAS), 13 inductively coupled plasma mass spectrometry (ICP-MS), 14,15 neutron activation analysis (NAA), 16 inductively coupled plasma-optical emission spectrometry (ICP-OES), 17 fluorometry, 18,19 requiring sample pretreatment steps such as ion-exchange, 20 solid phase extraction (SPE), 21,22 liquid phase microextraction (LPME), 23 and cloud point extraction (CPE). [24][25][26][27][28] CPE is superior to traditional solvent extraction because of its high extraction yield and preconcentration factor, and has several advantages such as simplicity, inexpensiveness, operational safety and use of non-toxic rea gents. 29,30 Before detection, CPE is used as a separation and preconcentration method using a surfactant to cause the generation of micellar surroundings and phase separation when a nonionic surfactant solution (or its mixture with cationic or anionic surfactant) as extractant is heated above the critical temperature.…”

“…In this sense, there are some publications dealing with CPE-spectrophotometric determination of vanadium in different sample matrices with their own advantages and disadvantages. [24][25][26][27][28] Moreover, solidified floating organic drop microextraction (SFODME) 37 and on-line temperature-assisted ionic liquid based dispersive liquid liquid microextraction (on line TA-IL-DLLME) 38 in combination with spectrophotometry as further preconcentration tools prior to analysis were also used for sensitive determination of vanadium in environmental samples.…”

Determination of Zinc, Copper, and Mercury in Water Samples by Using Novel Micro Cloud Point Extraction and UV-Vis Spectrophotometry

“…In our previous work, we introduced a new variant of CPE, named new micro cloud point extraction (MCPE), for the determination of two metals (uranium and vanadium) [43] and some organic dyes [44,45] in water samples in water samples. MCPE is a green and fast extraction method based on miniaturization of CPE.…”

Application of Dispersive Liquid-Liquid Microextraction in Narrow-Bore Tube for Preconcentration and Spectrophotometric Determination of Cadmium in Aqueous Samples

“…Therefore, for determination of traces of metals and achievement of low detection limits, a preconcentration and/or isolation step is necessary before introduction of samples to UV-visible spectrophotometry. Many methods have been proposed for preconcentration and separation of metals such as liquid-liquid extraction [14][15][16], cloud point extraction [12,17], coprecipitation [18][19][20][21], ion exchange [22,23], and membrane techniques [24][25][26]. The traditional liquid-liquid extraction method and other conventional separation methods are generally time-consuming and labor-intensive, and usually consume large amount of toxic organic solvents (with high purity), which after extraction procedures, have to be disposed of properly.…”