3-甲氧基-甲亚胺H分光光度法测定饮用天然矿泉水中硼酸

Determination of Boric Acid in Natural Mineral Water for Dinking by 1-(2-hydroxy-3-methoxybenzylidence-amino)-8-hydroxynaphalene-3-6-disulfonic Acid Spectrophotometry

研究了在 p H6 .5乙酸铵介质中 ,硼酸与 3-甲氧基 -甲亚胺 H(C1 8H1 5O9NS2 )显色反应条件。该配合物的 λmax=42 0 nm,硼酸浓度在 0 .4～ 6 .0 mg/ L范围呈良好的线性关系 ,检出限为 0 .0 8mg/ L ,表观摩尔吸光系数 (ε)为 4.6× 10 4L / (mol· cm )。在 EDTA存在下 ,方法有很好的选择性 。

The conditions of color reaction of boric acid with 1 (2 hydroxy 3 methoxybenzylidence amino) 8 hydroxynaphalene 3 6 disulfonic acid in buffer medium of ethamine at pH 6 5 were studied in the assy The maximum absorption wavelength of this coordination compound was 420 nm The coordination reaction showed a good linear relationship at the concentrations of boric acid of 0 4~0 6 mg/L The detection limit and molar absorptivity (ε) was 0 08 mg/L and 4 6×10 4 L/(mol·cm) respectively. This method presented perfect selectivity under the existence of EDTA solution,had been successfully applied in the determination of boric acid in natural mineral water for drinking