Method for the determination of priority pollutant metals by HPLC and UV-VIS spectrophotometry

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:7003870

Shofstahl, J H

Complexation of the priority pollutant metals with dibenzyldithiocarbamate, in conjunction with reverse phase liquid chromatography/ultraviolet-visible spectrophotometry, can be used to quantify ten of the thirteen metals designated a priority pollutants by the United States Environmental Protection Agency. Eight of these ten metals, referred to as the acid extractable complexes (Sb, Cd, Cr, Cu, Pb, Hg, Ni, and Se), are determined in one sample while the concentrations of the remaining two metals, (Zn and Tl) and one potential interference (Mn), designated the base extractable complexes, are determined from a second sample. Of the remaining three metals, Ag and Ar do not form extractable complexes with dibenzyldithiocarbamate, while Be was excluded due to its extremely low solubility in natural waters. Separation of each mixture is accomplished using a quaternary solvent system. The detection limits for the complexes range from 0.1 ppb (ng/ml) for selenium to 1.8 ppb for thallium using a 250 ml sample. The corresponding linear ranges extend to 150 ppm ({mu}g/ml) for selenium to 350 ppm for thallium. Dibenzyldithiocarbamic acid exhibits the ability to speciate between the two forms of Cr capable of existing in aqueous environments, since only Cr (VI) forms a complex with the compound. Detection of the Cr(VI)-DBDC complex by visible spectrophotometry at 498.8 nm provides detection limits of less than 1 ppb and a linear range to 500 ppm. The total Cr concentration and subsequently the concentration of Cr(III) present can be determined by oxidation of the Cr(III) to Cr(VI) using Ce(IV) and then using the procedure for the determination of Cr(VI).

• Research Organization: Akron Univ., OH (USA)
• OSTI ID: 7003870
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102* -- Chemical & Spectral Procedures
54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (1990-)
ACCURACY
ACETATES
ACETONITRILE
ALCOHOLS
ALKALINE EARTH METALS
ANTIMONY
ARSENIC
BERYLLIUM
CADMIUM
CARBOXYLIC ACID SALTS
CHEMICAL ANALYSIS
CHROMATOGRAPHY
CHROMIUM
COBALT
COMPLEXES
COPPER
DETECTION
ELEMENTS
EXTRACTION
FURANS
GROUND WATER
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
LEAD
LIMITING VALUES
LIQUID COLUMN CHROMATOGRAPHY
MANGANESE
MERCURY
METALS
METHANOL
NATIONAL ORGANIZATIONS
NICKEL
NITRILES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SOLVENTS
OXYGEN COMPOUNDS
PHOTOMETRY
POLLUTANTS
QUANTITATIVE CHEMICAL ANALYSIS
SELENIUM
SEMIMETALS
SEPARATION PROCESSES
SILVER
SOLUBILITY
SOLVENTS
SPECTRA
SPECTROSCOPY
SURFACE WATERS
TETRAHYDROFURAN
THALLIUM
TRANSITION ELEMENTS
ULTRAVIOLET SPECTRA
US EPA
US ORGANIZATIONS
VISIBLE SPECTRA
WATER
ZINC