Preconcentration Of Vanadium Research Articles

Determination of vanadium, manganese, silver and lead by graphite furnace atomic absorption spectrometry after preconcentration on silica-gel modified with 3-aminopropyltriethoxysilane

3-aminopropyltriethoxysilane modified silica-gel was used for the separation and preconcentration of vanadium, silver, manganese, and lead prior to their determination by graphite furnace atomic absorption spectrometry. Surface characteristics and surface area of the silica-gel before and after chemical modification were determined by elemental and surface area analysis. The retention and recovery of the analyte elements were studied by applying batch and column techniques. The experimental parameters, such as the effect of pH of the sample, shaking time in batch technique, flow rate of the eluent and the amount of silica, on retention and elution have been investigated. Vanadium, manganese, silver and lead were quantitatively (≥90%) recovered in the batch technique with R.S.D. values of 2.2, 1.9, 3.8 and 1.4%, respectively. The same recoveries were obtained in the column technique except for manganese, for which it was only 70%. Detection limits of the method for vanadium, manganese, silver and lead are 0.006, 0.002 0.0004 and 0.004 μg, respectively.

On-line pre-concentration system for vanadium determination in drinking water using flow injection-inductively coupled plasma atomic emission spectrometry

An on-line vanadium preconcentration and determination system implemented with inductively coupled plasma atomic emission spectrometry (ICP-AES) associated to flow injection (FI) was studied. For the retention of vanadium, 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and Amberlite XAD-7 were used, at pH 3.7. The vanadium was removed from the microcolumn in countercurrent with nitric acid. An enrichment factor (EF) of 75 was obtained. The detection limit value for the preconcentration of 50 ml of aqueous solution of vanadium was 0.04 μg l −1. The precision for 10 replicate determinations at the 5 μg l −1 vanadium levels was 2.5% relative standard deviation (R.S.D.), calculated with the peak heights obtained. The calibration graph using the preconcentration system for vanadium was linear with a correlation coefficient of 0.9996 at levels near the detection limits up to at least 50 μg l −1. The accuracy of the method was demonstrated by analysing a standard reference material NIST SRM 1640 trace elements in natural water. The method was successfully applied to the determination of vanadium in drinking water samples.

Determination of vanadium (V) in drinking water by flow injection and pre-concentration in a knotted reactor by inductively coupled plasma optical emission spectrometry with ultrasonic nebulization

An on-line vanadium pre-concentration and determination system implemented with inductively coupled plasma optical emission spectrometry (ICP-OES) associated with a flow injection (FI) method with ultrasonic nebulization (USN) system was studied. The vanadium was retained as vanadium-2-(5-bromo-2-pyridylazo)-5-diethylaminophenol V(V)-(5-Br-PADAP) complex, at pH 3.2. The vanadium complex was removed from the knotted reactor (KR) with 30% v/v nitric acid. A sensitivity enhancement factor of 180 was obtained with respect to ICP-OES using pneumatic nebulization (15 for USN and 12 for KR). The value of detection limit for the pre-concentration of 10 ml of aqueous solution was 19 ng l −1. The precision for 10 replicate determinations at the 5 μg l −1 V(V) level was 2.6% relative standard deviation (R.S.D.), calculated with the peak heights obtained. The calibration graph using the pre-concentration system for vanadium was linear with a correlation coefficient of 0.9995 at levels near the detection limits up to at least 100 μg l −1. The method was successfully applied to the determination of vanadium in drinking water samples.

Speciation of vanadium (IV) and vanadium (V) with Eriochrome Cyanine R in natural waters by solid phase spectrophotometry

The separation and preconcentration of vanadium (IV) and vanadium (V) using Sephadex DEAE A-25 with Eriochrome Cyanine R has been studied, based on the preconcentration of vanadium (IV) in the first step and V(V) after reduction with ascorbic acid in the second step. Factors affecting the optimum fixation of the complex were investigated. The absorbance of the solid phase is measured directly at 563 nm for V(IV), at 585 nm for V(V) and at 750 nm for both. The proposed method provides a simple and specific procedure for the separation of vanadium in natural waters. The calibration graph is linear up to 150 ng/mL, with RSD of 4.7% for V(IV) and 4.0% for V(V). The detection limits are 1.6 and 1.4 ng/mL for V(IV) and V(V), respectively.

Mutual separation and preconcentration of vanadium(V) and vanadium(IV) in natural waters with chelating functional group immobilized silica gels followed by determination of vanadium by inductively coupled plasma atomic emission spectrometry

The mutual separation and preconcentration of VV and VIV using chelating functional group immobilized silica gels (CISs) has been studied, based on inductively coupled plasma atomic emission spectrometric detection. Ethylenediamine-bonded (ED–CIS) and ethylenediaminetriacetate-bonded (ED3A-CIS) silica gels were used. A two-column system consisting of a first column of ED–CIS and a second column of ED3A-CIS was developed for on-line separation and preconcentration of VV and VIV. In the pH range 2.5–3.0, ED–CIS retains VV and separates it completely from VIV, whereas ED3A-CIS collects both VV and VIV. The second column can be used to preconcentrate VIV in the breakthrough solution from the first column. Separation is achieved with recoveries of 91–105%. The recovery of both ions is 98% or better. An enrichment factor of 40 is obtained, with which the detection limit of V with inductively coupled plasma atomic emission spectrometry is improved down to 60 pg ml–1. The method was applied successfully to V speciation in natural waters.

Oxidation product of ammonium pyrrolidin-1-yldithioformate as a coprecipitator for the preconcentration of vanadium, cobalt, zinc, arsenic, iron, cadmium, selenium and mercury from aqueous solution

The use of ammonium pyrrolidin-1-yldithioformate [ammonium pyrrolidinedithiocarbamate (APDC)] as a complexing agent for V, Co, Fe, Cu, Zn, As, Cd, Se and Hg, and its oxidation product as a collector, for the preconcentration of these elements from aqueous solutions, has been studied. All these elements are simultaneously concentrated 1600-fold in a single precipitate of the collector. The coprecipitation depends on the concentration of APDC in aqueous solution and the pH. The recoveries are generally greater than 93% although some exceptions are noted. The method can be recommended for the preconcentration of the elements in the analysis of natural waters and for the purification of MnCl2 solution in the presence of Co, Fe, Cu, Cd, Hg and other transition elements. In this instance, the recovery yields are greater than 92%.

Flow injection flame atomic absorption spectrometry system for the pre-concentration of vanadium(V) and characterisation of vanadium(IV) and -(V) species

Download options Please wait... Article information DOI https://doi.org/10.1039/JA9890400195 Article type Paper Download Citation J. Anal. At. Spectrom., 1989,4, 195-198 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Flow injection flame atomic absorption spectrometry system for the pre-concentration of vanadium(V) and characterisation of vanadium(IV) and -(V) species B. Patel, S. J. Haswell and R. Grzeskowiak, J. Anal. At. Spectrom., 1989, 4, 195 DOI: 10.1039/JA9890400195 To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Bharti Patel Stephen J. Haswell Roman Grzeskowiak

Microdetermination of vanadium in water samples.

The proposed method incorporates preconcentration of vanadium in water samples by its coprecipitation on ferric hydroxide at pH 8.0-9.6 which is redissolved in sulphuric acid; this is followed by extraction with N-phenylbenzohydroxamic acid (PBHA). The precision and accuracy of the newly developed method was ascertained by analysing EPA (Environmental Protection Agency, U.S.A.) standard water samples.

The determination of vanadium in sea and surface waters

A simple and sensitive method for the determination of vanadium in sea and surface water is presented. The method is based on preconcentration of vanadium on active charcoal at a pH 3.6±0.2, followed by instrumental neutron activation analysis of the charcoal adsorbers and measurement of52V (T=3.71 m). The limit of the determination, which is set by the blank value of the charcoal, is 0.01 μg V·1−1. Data are given for Dutch sea and surface water.