Determination of C, H, N, S, and X in inorganic materials by the generalized method.

Generalized method for determination of nonmetallic elements in inorganic materials. II.

Abstract

The generalized method for determination of C, H, N, S and X presented in the preceding report was applied for many inorganic compounds and their mixtures, and satisfactory results were obtained except for several alkaline earth sulfates.
Based on the further investigations on the conditions for decomposition and determination, the authors recommended a method as follows : For the determination of C, H, S and X, the sample (3050 mg) was heated at 1000°C (or at 1300°C provided that the sample contained alkaline earth sulfate) with an addition of 500 mg WO₃ in the current of oxygen, and the C, H, S, and X were converted into CO₂, H₂O, SO₃, and X₂, respectively, by use of a platinum catalyst, and each of them was determined by gravimetry. The N in sample was converted into N₂ in the presence of CuO-Cu under CO₂ current, and determined directly by gas volumetric method.
The error in the proposed method for each element was within±0.5%, and the lower limit of determination was around 1%.