Direct determination of trace elements in coal: Wavelength‐dispersive X‐ray spectrometry with matrix correction using compton scattered radiation

Abstract

An X-ray fluorescence method is described for the direct determination, without pretreatment, of up to 55 trace elements in coal and coal-derived materials. A single assay specimen is prepared by blending finely crushed sample with a binder and briquetting. Calibration is effected by a suite of synthetic calibration standards prepared from spectrographically pure materials blended into graphite. Variations in ash and sulphur content required matrix absorption corrections to analyte and background intensities, which were achieved by use of relationships with the measured Compton scattered radiation. Prior knowledge of or assumptions concerning the composition of the coal are not required. Accurate results are presented for three NBS coal standard reference materials. Certain elements (including T1, Hg, Te, In, Cd, Ag and most rare earths) are normally present in coal at levels below the detection capability of the described method and require quantification by alternative techniques. 0 Heyden

Modern Methods in Bituminous Coal Analysis: Trace Elements

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X‐ray fluorescence analysis of Co, Ni, Pd, Ag, and Au in the scrapped printed‐circuit‐board ash

“…It is known that printed circuit boards have various components with wide variations in concentration . Scattered X‐ray intensities are used as internal standards to correct matrix effects . Correction with scattered X‐ray intensities is based on the theory that the mass absorption coefficients of samples are inversely proportional to the intensities of scattered X‐ray, and the method is simple and reliable.…”

Combustion Behavior of Spanish Lignocellulosic Briquettes

“…This is vital for their correct use in combustion systems. The determination of these parameters by means of a quick and nondestructive technique, such as measurement of the natural activity of gamma rays of the lignocellulosic briquettes (Alvarez and Dopíco, 1991) or dispersive X-ray fluorescence (Ayala et al, 1994;Míguez et al, 2002;Mills et al, 1981) is a topic of great interest. The reactivity of waste and biomass varies widely from one type of fuel to another.…”