Evaluation of Commercial Energy Dispersion X-Ray Analyzers for Water Pollution

Abstract

Seven typical commercial energy dispersion x-ray analyzers were evaluated for application to the measurement of elemental concentration in polluted water. Sensitivity and detection limits were measured on single- (or dual-) element standards. Results for 400-sec counting intervals indicate that the better energy dispersive analyzers have limits of detection between 10 and a few hundred µg/cm². Many pollutants in natural water are present at >10 ppb, which means that adequate material can be obtained from 100 to 1000 ml samples; some elements of interest such as Cd and Sn are generally present at <1 ppb, which makes practical detection marginal for the energy dispersion method. When x-ray calibration curves were prepared from individual-element gravimetric standards and used to analyze multiple-element samples (also prepared gravimetrically), the agreement between x-ray and gravimetric results showed an average relative deviation of 16%.

Keywords

Energy dispersion X-ray analysis Water pollution

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References

Birks

L. S.

Gilfrich

J. V.

, and Burkhalter

P.G.

Development of X-Ray Fluorescence Spectroscopy for Elemental Analysis of Particulate Matter in the Atmosphere and in Source Emissions, Environmental Protection Agency Report R2-72-063 (Oct. 1972).

Birks

L. S.

and Gilfrich

J. V.

, Development of X-Ray Fluorescence Spectroscopy for Elemental Analysis of Particulate Matter in the Atmosphere and in Source Emisions. Phase II: Evaluation of Commercial Multiple Crystal Spectrometer Instruments, Environmental Protection Agency Report EPA-650/2-73-006 (June 1973), also Naval Research Laboratory Report 7616 (June 1973).

Birks

L. S.

and Gilfrich

J. V.

, Low Cost Compact X-Ray Fluorescence Analyzer for On-Site Measurements of Trace Elements in Source Emissions, Environmental Protection Agency Report EPA 600/4-75-002 (July 1975), also Naval Research Laboratory Report 7926 (Aug. 1975).

Burkhalter

P. G.

, Trace Metal Water Pollutants Determined by X-Ray Fluorescence, Naval Research Laboratory Report 7637 (Aug. 1973).

International Union of Pure and Applied Chemistry, Nomenclature, Symbols, Units and Their Usage in Spectrochemical Analysis —II. Data Interpretation, Pure Appl. Chem. 45, 99 (1976).