Wet ashing of coal with perchloric acid mixed with periodic acid for the determination of sulphur and certain other constituents

A method is described for the determination of sulphur and some other inorganic constituents of coal. Organic matter is destroyed by wet combustion with perchloric acid and periodic acid. The method is rapid and efficient. Silica and sulphur are determined gravimetrically, iron, aluminium, vanadium, titanium, phosphorus, and arsenic spectrophotometrically, and calcium and magnesium volumetrically. No loss occurred by volatilisation. The complete analysis scheme devised was applied to a bituminous coal of Iowa origin.