クリスタルバイオレットと2,3-ナフタレンジオールによるホウ素の溶媒抽出-吸光光度定量
1980 年 29 巻 10 号 p. 729-731
詳細
1980 年 29 巻 10 号 p. 729-731
A highly sensitive and selective method for the spectrophotometric determination of boron was developed. Boron reacted with 2, 3-naphthalenediol to form a complex anion extractable into chlorobenzene in the presence of Crystal Violet. Boron can therefore be indirectly determined by measuring the absorbance of the Crystal Violet in the extract at 595 nm. The calibration curve was linear in the range of (1.6 × 10-68 × 10-6) M boron and the apparent molar absorptivity was 1 × 105 l mol-1 cm-1 at 595 nm. The following ions did not interfere even at 400-fold molar ratio to boron; Mg(II), Ca(II), Co(II), Cd(II), Zn(II), Cl-, Br-, I-, NO3- and SO42-. But 400-fold amounts of perchlorate or thiocyanate gave a slightly negative error. Metal ions such as Al(III) and Fe(III) interfered when present in amounts 50-fold that of boron. However, these ions could be tolerated up to about 400-fold molar amounts by adding EDTA to the sample solution at a concentration of 2.0 × 10-2 M.
