Analytical Sciences


Abstract − Analytical Sciences, 22(3), 461 (2006).

Investigation of the Drying Conditions for Amidosulfuric Acid
Toshiaki ASAKAI,* Ryota MINEGISHI,** Norie INABA,* Yutaka ISHIMURA,* Mariko MURAYAMA,* and Tatsuhiko TANAKA**
*National Institute of Technology and Evaluation, 2-49-10, Nishihara, Shibuya-ku, Tokyo 151-0066, Japan
**Faculty of Engineering, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
The drying conditions for primary standards of volumetric analysis have a significant effect on the titration results due to changes in the purity, stability and homogeneity. Amidosulfuric acid, a strong acid used as a reference material for volumetric analysis in Japan, was dried in a vacuum desiccator or heated at different temperatures, and then measured by Karl-Fischer titration, thermogravimetry/mass spectroscopy (TG-MS), ion chromatography and coulometric titration. The optimum drying conditions were at 50°C for 24 h with crushing.