The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Pinky Hotwany - One of the best experts on this subject based on the ideXlab platform.
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Solid phase extraction of chromium(VI) from aqueous solutions by adsorption of its Diphenylcarbazide complex on an Amberlite XAD-4 resin column.
Journal of hazardous materials, 2007Co-Authors: N. Rajesh, Rohit Kumar Jalan, Pinky HotwanyAbstract:A method has been developed for the solid phase extraction of chromium(VI) based on the adsorption of its Diphenylcarbazide complex on an Amberlite XAD-4 resin column. The influence of acidity, stability of the column, sample volume, flow rate and interfering ions were studied in detail. The adsorbed complex could be eluted using acetone-sulfuric acid mixture and the concentration of chromium was determined using visible spectrophotometry. A detection limit of 6 microg L(-1) could be achieved. A preconcentration factor of 27 could be obtained for 400 mL sample volume. The validity of the method was checked in spiked water samples and electroplating wastewater.
Anthony D. Symons - One of the best experts on this subject based on the ideXlab platform.
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Response of chromium(V) to the Diphenylcarbazide spectrophotometric method for the determination of chromium(VI)
Analytica Chimica Acta, 1991Co-Authors: J.m. Eckert, Robert J. Judd, Peter A. Lay, Anthony D. SymonsAbstract:Abstract Two chromium(V) complexes are shown to respond to the Diphenylcarbazide spectrophotometric method for the determination of chromium(VI), but with only 60% of the efficiency of Cr(VI). Acidification to pH 1–2 in the presence of dissolved organic matter results in substantial reduction of the Cr(V) within 24 h.
Dongxing Yuan - One of the best experts on this subject based on the ideXlab platform.
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automated syringe pump based flow batch analysis for spectrophotometric determination of trace hexavalent chromium in water samples
Microchemical Journal, 2019Co-Authors: Xiangyu Zhu, Yao Deng, Dongxing YuanAbstract:Abstract In this work, we established an automated spectrophotometric method for determining hexavalent chromium in water samples using an integrated syringe pump-based environmental water analyzer (iSEA) based on the classic 1,5‑Diphenylcarbazide chemistry. The device was computer-controlled with programs written by LabVIEW. The effects of reagent concentration, sample salinity and foreign ion interferences were investigated. Standard solutions (GBW(E)081584-1) were used to test the accuracy of the method. When equipped with a 5 cm Z-shaped flow cell, the detection limit was 0.024 μM with sample throughput of >30 h−1. In order to meet the requirements for trace Cr(VI) determination, the system was modified with a 2.5 m liquid waveguide capillary cell (internal diameter of 0.55 mm). The sample consumption was
N. Rajesh - One of the best experts on this subject based on the ideXlab platform.
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SOLID PHASE EXTRACTION OF CHROMIUM (VI) FROM AQUEOUS SOLUTIONS BY ADSORPTION OF ITS Diphenylcarbazide COMPLEX ON AN ALUMINA COLUMN
The Canadian Journal of Chemical Engineering, 2008Co-Authors: N. Rajesh, Vikas Agarwal, S. AarthyAbstract:A simple method has been developed for the solid phase extraction of chromium (VI) based on the adsorption of its Diphenylcarbazide (DPC) complex on an alumina column. The effect of various parameters such as acidity, stability of the column, sample volume, and interfering ions have been studied in detail. The adsorbed complex could be easily desorbed using sulphuric acid and the concentration of chromium has been established using atomic absorption spectrophotometry and visible spectrophotometry. The calibration graph was linear in the range of 0–1 µg/mL chromium (VI) with a detection limit of 4 µg/L. A highest preconcentration factor of 125 could be obtained for 5000 mL sample volume using glass wool as support for alumina. Chromium (VI) could be effectively separated from other ions such as zinc, nickel, copper, chloride, sulphate, and nitrate and the method has been successfully applied to study the recovery of chromium in spiked well water and tap water samples. On a mis au point une methode simple pour l'extraction en phase solide du chrome (VI) basee sur l'adsorption de son complexe Diphenylcarbazide sur une colonne d'alumine. L'effet de divers parametres, tels que l'acidite, la stabilite de la colonne, le volume des echantillons, les ions d'interference, etc., a ete etudie en detail. Le complexe adsorbe a pu etre facilement desorbe a l'aide d'acide sulfurique et la concentration de chrome a ete etablie par spectrometrie a absorption atomique et par spectrophotometrie. Le graphe de calibration est lineaire dans la gamme de chrome de 0–1 µg/mL (VI) avec une limite de detection de 4 µg/L. Un facteur de preconcentration plus eleve (125) a pu etre obtenu pour un volume d'echantillon de 5000 mL en utilisant de la laine de verre comme support pour l'alumine. Le chrome (VI) a pu etre separe efficacement des autres ions tels le zinc, le nickel, le cuivre, le chlorure, le sulfate, le nitrate, etc., et la methode a ete appliquee avec succes pour etudier la recuperation de chrome dans des echantillons d'eau de puits et d'eau de robinet reconstituees.
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Solid phase extraction of chromium(VI) from aqueous solutions by adsorption of its Diphenylcarbazide complex on an Amberlite XAD-4 resin column.
Journal of hazardous materials, 2007Co-Authors: N. Rajesh, Rohit Kumar Jalan, Pinky HotwanyAbstract:A method has been developed for the solid phase extraction of chromium(VI) based on the adsorption of its Diphenylcarbazide complex on an Amberlite XAD-4 resin column. The influence of acidity, stability of the column, sample volume, flow rate and interfering ions were studied in detail. The adsorbed complex could be eluted using acetone-sulfuric acid mixture and the concentration of chromium was determined using visible spectrophotometry. A detection limit of 6 microg L(-1) could be achieved. A preconcentration factor of 27 could be obtained for 400 mL sample volume. The validity of the method was checked in spiked water samples and electroplating wastewater.
Leticia López-martínez - One of the best experts on this subject based on the ideXlab platform.
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Enhanced spectrophotometric determination of chromium (VI) with Diphenylcarbazide using internal standard and derivative spectrophotometry.
Talanta, 1997Co-Authors: Kazimierz Wrobel, P. L. López-de-alba, Leticia López-martínezAbstract:Abstract In the present work, erioglaucine A was applied as internal standard to enhanced spectrophotometric determination of chromium (VI) with Diphenylcarbazide. The following procedure was used: (1) addition of internal standard and formation of ion pairs of Cr (VI) with benzyltributylammonium bromide (BTAB) (sample volume 100 ml), (2) extraction to 10 ml of methylene chloride, (3) evaporation in nitrogen stream, and (4) redissolution in a micro-volume with addition of Diphenylcarbazide for color development (final volume 200 μl). The preconcentration factor achieved was about 400 and it was shown that, using internal standard, the analytical errors due to sample treatment were reduced. The analytical signals for chromium and internal standard were obtained at 591.30 and 653.50 nm from first derivative spectra, normalized against 1D653.50nm. The analytical characteristics evaluated were: detection limit = 0.06 μg l−1, quantification limit = 0.19 μg l−1, precision for 1 μg l−1 14.2%, and for 10 μg l−1 3.2%, correlation coefficient of linear regression was 0.9985. The proposed procedure was applied to determination of chromium (VI) in tap water. Total chromium was determined by electrothermal atomic absorption spectrometry, the recovery of hexavalent chromium added was then evaluated and compared with the results of the proposed procedure. In this experiment, good agreement was obtained between results obtained by the two methods.