Slurry-injection atomic absorption spectrometry for analysis of whole coal

A method is described which permits the determination of a wide variety of major-, minor-, and trace-level elements directly in powdered whole coal by aspiration of aqueous slurries into a conventional atomic absorption spectrophotometer. Relative precisions and accuracles are in the range of +- 1 to 5% and 5 to 25%, respectively. The relative atomization efficiencies of almost every element studied are remarkably constant; an element in a coal matrix will produce an absorption signal 20 +- 6% that of a purely aqueous solution of equivalent concentration. The details of sample preparation, the most critical aspect of the entire procedure, and which must be carefully and reproducibly performed, are given. Considerable savings in operator and turnaround times over normal ashing-acid-dissolution procedures can be achieved. 6 figures, 7 tables.