Application of X-Ray-Fluorescence Spectrometry to the Analysis of Ta-Nb-Sn Slags and Associated By-Products

This paper describes the development of an accurate, precise, and rapid analytical procedure using x-ray-fluorescence spectrometry for the determination of Nb, Ta, Mg, Al, Si, P, K, Ca, Ti, Mn, Fe, Zr, and Sn in a wide variety of materials resulting from the processing of Ta-Nb-Sn slags to produce Ta-Nb oxides. The method involves evaporation of all the liquids to dryness, a 1:8 fusion of the solid materials with a flux consisting of Na-Li tetraborate and Na2CO3, and the addition of La oxide as a heavy absorber. With the use of a computer program, residual matrix effects are corrected for by influence-factor calculations.

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Slope-Ratio Technique for the Determination of Trace Elements by X-Ray Spectroscopy: A New Approach to Matrix Problems

Applied Spectroscopy ◽

10.1366/000370268774383147 ◽

1968 ◽

Vol 22 (4) ◽

pp. 321-324 ◽

Cited By ~ 8

Author(s):

Frank Cuttitta ◽

Harry J. Rose

Keyword(s):

Trace Elements ◽

Matrix Effects ◽

Fluorescence Analysis ◽

Slope Ratio ◽

New Approach ◽

X Ray ◽

Standard Curve ◽

Residual Matrix ◽

Matrix Problems

A new approach to solving matrix problems in x-ray fluorescence analysis of trace elements has been applied to the determination of bromine in saline waters and zinc in silicates. The method requires no prior knowledge of the chemical composition of the sample. Marked matrix effects are minimized by dilution, and the problem of variable backgrounds due to residual matrix effects is solved by using a slope-ratio technique. In this proposed technique, the slope of a standard curve prepared from pure solutions is compared with that of spiked samples. The ratio of the slopes of these two curves permits the calculation of an adjusted background which does not significantly differ from that of an absorbent impregnated with the sample matrix free of the element sought. Experimental parameters concerning the technique are presented. The excellent agreement of the zinc and bromine data with analytical results obtained by more conventional methods suggests that the technique can be used for the determination of other trace constituents in geologic materials. Application of the slope-ratio technique to other modes of instrumental analysis appears feasible.

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Simultaneous Determination of Low Parts-per-Billion Level Pb and as in Waters Using Energy-Dispersive X-Ray Fluorescence Spectrometry

Applied Spectroscopy ◽

10.1366/0003702011951920 ◽

2001 ◽

Vol 55 (3) ◽

pp. 298-306 ◽

Cited By ~ 9

Author(s):

Terrance D. Hettipathirana ◽

Lester H. Smith ◽

Keith Norrish

Keyword(s):

Simultaneous Determination ◽

Matrix Effects ◽

Certified Reference Materials ◽

Ferric Hydroxide ◽

Standard Addition ◽

Energy Dispersive ◽

Fluorescence Spectrometry ◽

Simple Method ◽

X Ray

A simple method is described for the simultaneous determination of low parts-per-billion levels of As and Pb in waters. The method is based on the preconcentration of analytes by adsorbing them onto hydrous ferric hydroxide (HFO) impregnated into the 13 mm diameter area at the center of 32 mm diameter circular disks cut from Whatman filter papers. The adsorbed analytes are determined by using thin-layer energy-dispersive X-ray fluorescence spectrometry. The X-ray intensity of As and Pb adsorbed onto HFO is linearly proportional to the concentration up to 80 μg/L. The precision of the method is ∼ 0.5–5%, and the method detection limit for Pb and As in seawater is 0.63 and 0.21 μg/L, respectively. The method was validated by analyzing the certified reference materials SLRS-3 (riverine water), CASS-4 (nearshore seawater), and NASS-5 (offshore seawater) for As. The adsorption characteristics of Pb, As(III), As(V), Se(IV), Se(VI), and Hg onto the HFO impregnated disks, the interspecies adsorption effects, and the use of the standard addition method to compensate for matrix effects are also presented.

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