工業用無水フタル酸中の無水マレイン酸とα-ナフトキノンとの同時定量

概要

論文の詳細を見る
A rapid and simple method of simultaneous determination of maleic anhydride and α-naphthoquinone in commercial phthalic anhydride by polarographic method has been investigated. It was found that these substances showed good waves in acidic medium and in well separated form. Since the waves had enough room to add that of the fourth substance, simultaneous determination was possible from an only series of polarogram including the wave of lead as an internal standard. In the determination, a mixture of an aqueous solution of phthalic anhydride and a solution of lead nitrate in 0.1 <I>N</I> nitric acid was made. A straight calibration line for the mixture of pure substances was obtained with a precision of 0.01% to total amount of sample.