Determination of Fluorine in Silicon Carbide Powder by Combustion Ion Chromatography

MINAMI Hideaki, YAMANASHI Masaki, SHIOMI Shohei, MARUOKA Tomoki

doi:10.2116/bunsekikagaku.68.265

<p>An analysis method for fluorine in silicon carbide by combustion ion chromatography was optimized. We examined the quantitative values of fluorine, the change of mass and the crystal structure of silicon carbide for each combustion condition, such as the combustion temperature, combustion time and carrier gases (air, mixed air, argon and nitrogen) with a humid or dry condition. As a result, the quantitative values of fluorine in two certified standard silicon carbides (α-phase, 8001a; and β-phase, 8002a) for fine ceramics under the combustion conditions of all carrier gases with humid conditions, in 1200°C combustion temperature and 30 minutes combustion time, were within each reference value ± expanded uncertainty of certified standards. In both 8001a and 8002a, the quantitative values of fluorine under the condition of air and mixed air flow were lower than those of argon and nitrogen flow by about 30 mg kg⁻¹. This seemed to involve the influence by oxygen during combustion. On the other hand, under dry conditions, the quantitative values of fluorine in both 8001a and 8002a, were within the reference values ± an expanded uncertainty in air and mixed air flow conditions. In argon and nitrogen flow, however, the quantitative values of fluorine were about half of the reference value. It was suggested that the existence of oxygen or moisture contained in the carrier gas was important for the extraction of fluorine. Further investigation is required concerning the influence of the oxygen and moisture contained in the carrier gas and of the dissolved oxygen concentration in water used at the humidifying unit. The mass in both 8001a and 8002a samples had increased after combustion, and the behavior of the mass change greatly differed depending on the crystal structure difference. There was no correlation between the pairs involving the quantitative value of fluorine, between the quantitative value of fluorine and the mass change, between the quantitative value of fluorine and crystal structure change.</p>

Determination of Fluorine in Silicon Carbide Powder by Combustion Ion Chromatography

Bibliographic Information

Search this article

Abstract

Journal

Keywords

Details 詳細情報について

Export

Report a problem