Separation and preconcentration of Cr(VI) as ion associate using solid phase extraction

OTRUBA, Vítězslav, Jan PIVNIČKA and Viktor KANICKÝ. Separation and preconcentration of Cr(VI) as ion associate using solid phase extraction. Collection of Czechoslovak Chemical Communications. Prague: IOCB, 2000, vol. 65, No 12, p. 1865-1874. ISSN 0010-0765.

Basic information

• Original name: Separation and preconcentration of Cr(VI) as ion associate using solid phase extraction
• Authors: OTRUBA, Vítězslav (203 Czech Republic), Jan PIVNIČKA (203 Czech Republic) and Viktor KANICKÝ (203 Czech Republic, guarantor).
• Edition: Collection of Czechoslovak Chemical Communications, Prague, IOCB, 2000, 0010-0765.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10406 Analytical chemistry
• Country of publisher: Czech Republic
• Confidentiality degree: is not subject to a state or trade secret
• Impact factor: Impact factor: 0.960
• RIV identification code: RIV/00216224:14310/00:00002852
• Organization unit: Faculty of Science
• UT WoS: 000167546600004
• Keywords in English: Hexavalent chromium; solid phase extraction; ion associate; flame emission spectrometry
• Tags: flame emission spectrometry, Hexavalent chromium, Ion associate, Solid Phase Extraction
• Tags: Reviewed

Abstract

Cr(VI) was preconcentrated as ion associate of chromate with quaternary onium salts on C18 modified silicagel.After elution with ethanol, Cr was determined by flame emission spectrometry.

Abstract (in Czech)

A method of separation and preconcentration of Cr(VI) was developed based on sorption on modified silica gel (C18) of an ion associate of Cr(VI) anion with a quaternary base. The study was performed with the following quaternary onium salts: [1-(ethoxycarbonyl)-pentadecyl]trimethylammonium bromide, 1-hexadecylpyridinium chloride, benzyl(dodecyl)dimethylammonium bromide, butyl(triphenyl)phosphonium bromide and tetraphenylarsonium chloride. Benzyl(dodecyl)dimethylammonium bromide was found the optimum ion-pairing reagent. Sample containing Cr(III) and Cr(VI) in the presence of 0.005 mol/l of benzyl(dodecyl)dimethylammonium bromide was pumped with a peristaltic pump through the column containing the sorbent. The optimum pH range 4-5 was maintained with 0.05 mol/l phosphate buffer. Elution was accomplished using 95 vol.% ethanol and the recovery of Cr(VI) was (96 +/- 6)% in the concentration range 0.005-1 mg/l of Cr(VI); even in a tenfold excess of Cr(III) the recovery of Cr(VI) was 99.8% with the relative standard deviation of repeatability about 2.4% Cr in the eluate was determined by emission flame spectrometry (Cr I 425.435 nm) in an air-acetylene or N2O-acetylene flame with the limits of detection 10 or 2 ng/ml, respectively. Hence, with a typical preconcentration factor of 200, the limits of detection in natural aqueous samples were 50 and 10 pg/ml, respectively. Calibrations were linear at least up to 10 mg/l.

Links

• VS97020, research and development project: Name: Laboratoř plazmových zdrojů pro chemickou analýzu

Investor: Ministry of Education, Youth and Sports of the CR, Laboratory of plasma sources for chemical analysis