Liquid chromatographic separation of aqueous species of Cr(VI) and Cr(III)

Collins, Carol H.; Pezzin, Sérgio Henrique; Rivera, José Francisco Lugo; Bonato, Pierina Sueli; Windmöller, Cláudia Carvalhinho; Archundia, C.; Collins, Kenneth E.

doi:10.1016/s0021-9673(97)00676-6

Cited by 33 publications

(18 citation statements)

References 79 publications

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“…For oxidation-ion exchange treatment of synthetic, alkaline, plating wastewater, 2.7 g CuCl 2 и 2H 2 O and 3.1 g NaCN were dissolved in water to convert copper to the Cu(CN) 3 2Ϫ complex and leave some free excessive cyanide in solution. This solution was treated with 85 mL of 2 M hypochlorite solution (containing 37.25 g NaOCl per 250 mL solution) and left overnight.…”

Section: Methodsmentioning

confidence: 99%

Recovery of Copper (Ii) and Chromium (Iii,vi) From Electroplating-Industry Wastewater by Ion Exchange

Yalçın

Apak

Hızal

et al. 2001

Separation Science and Technology

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Two laboratory-scale separation processes have been developed for the recovery of copper (II) from acidic and cyanide-containing alkaline wastewater of electroplating industries. Acidic bath wastes were treated with Dowex 50X8, a strongly acidic cation-exchange resin, and the retained copper was eluted with H 2 SO 4 . The cyanide-containing alkaline bath waste was first oxidized with excessive hypochlorite, then neutralized, and recovered by the use of Amberlite IRC-718 chelating resin. Copper was eluted with H 2 SO 4 .The two different valencies of chromium have been recovered from electroplating-industry wastewater by different separation processes: The predominant valency, Cr(VI), was retained on a strongly basic Dowex 1X8 resin and eluted with a NaCl and ORDER REPRINTS NaOH solution. Alternatively, Cr(III), either existing originally in electroplating-industry waste-rinse mixtures or converted from Cr(VI) by reduction with Na 2 SO 3 , could be recovered by a weakly acidic Amberlite IRC-50 resin and eluted with a solution containing H 2 O 2 and NaOH. Where plating industry wastes contain high levels of organic contamination, Cr(VI) would be naturally reduced to Cr(III) upon acidification, and it may be more economical to recover all chromium as Cr(III).

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Section: Methodsmentioning

confidence: 99%

Recovery of Copper (Ii) and Chromium (Iii,vi) From Electroplating-Industry Wastewater by Ion Exchange

Yalçın

Apak

Hızal

et al. 2001

Separation Science and Technology

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“…Our results show that it is not possible to explain the adsorption behaviour of complexes plainly by surface charges of sorbents. Although since the early 1980s there have been research papers pointing out the high percentage of organically bounded Cr(III) (ca 60% in seawater) and Cr(III) complexes, chromium speciation methods depending on ion-exchange mechanism have been appearing in the literature (Nakayama et al, 1981;Collins et al, 1997;Stasinakis et al, 2003;Srivastava et al, 1998). Separation of chromium species via ion exchange would fail due to simultaneous retention of Cr(VI) and negatively charged complexes of Cr(III).…”

Section: Adsorption Behavior Of Cr (Iii) Complexesmentioning

confidence: 99%

Effect of organic Cr(III) complexes on chromium speciation

Uluçinar¹,

Onar²

2005

Chemical Speciation & Bioavailability

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Chromium speciation in the presence of organic chromium(III) complexes was investigated using solid-phase extraction. The adsorptions of Cr(VI) and Cr(III) on alumina and pumice powder were studied. Maximum sorption of Cr(VI) was obtained by alumina (90.22%), while Cr(III) was highly adsorbed onto pumice powder (86.65%). This result shows that pumice may be a new and promising adsorbent for Cr(III). The experimental equilibrium data for Cr(VI) adsorption onto alumina and Cr(III) sorption onto pumice were analysed using Langmuir and Freundlich isotherms. The separation and adsorption of Cr(VI), Cr(III) and five organic chromium(III) complexes onto pumice and alumina at different pH values were evaluated. Ethylenediaminetetraacetate (EDTA), oxalate, citrate, glycine, alanine and 8-hydroxyqinoline were used as ligands. Sorption of alanine and ethylenediaminetetraacetate complexes was higher onto alumina than pumice at pH43. The enhancement of adsorption of chromium(III) complexes onto pumice was achieved by surface modification of pumice using a surfactant, namely hexadecyltrimethylammoniumbromˇr (HDTMA). The presence of surfactant enhanced the adsorption of Cr(III) citrate, oxalate, glycine and 8-hydroxyquinoline complexes onto pumice. However, the adsorption of EDTA and alanine complexes decreased, with ratio of 13.40% and 4.00% respectively. Here we demonstrate that chromium speciation methods depending on adsorption onto various adsorbents including alumina may lead erroneous results. Analytical measurements were performed by flame AAS, data were obtained by standard addition method.

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“…This means that it is important and necessary for us to distinguish Cr 3+ from Cr 6+ in water. An extensive literature search indicates that reported methods for measuring Cr include the following: UV-VIS spectrophotometry, 11,12 high-performance liquid chromatography, 13 high performance liquid chromatography-ultraviolet spectrophotometry, 14 atomic absorption spectrometry (AAS), [15][16][17] flow injection-solid phase spectrophotometry 18 and atomic emission spectrometry, [19][20][21][22] capillary electrophoresis, 23 catalytic cathodic stripping voltammetry, 24 and mass spectrometry. 25 However, the rapidly selective quantification of Cr 3+ and Cr 6+ still appears to be a hot point of study since they normally coexist in water.…”

Section: Introductionmentioning

confidence: 99%

Estimation of Cr(III) in Water with the Presence of Cr(VI) by Chlorophosphonazo I Color Reaction Spectrophotometry

Zhang

2018

ANAL. SCI.

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Liquid chromatographic separation of aqueous species of Cr(VI) and Cr(III)

Cited by 33 publications

References 79 publications

Recovery of Copper (Ii) and Chromium (Iii,vi) From Electroplating-Industry Wastewater by Ion Exchange

Recovery of Copper (Ii) and Chromium (Iii,vi) From Electroplating-Industry Wastewater by Ion Exchange

Effect of organic Cr(III) complexes on chromium speciation

Estimation of Cr(III) in Water with the Presence of Cr(VI) by Chlorophosphonazo I Color Reaction Spectrophotometry

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