【摘要】 二苯胺磺酸钠在酸性溶液中遇到NaNO2时,氧化为二苯联苯胺磺酸紫。由于该氧化物不稳定,分解产物再与NO-2发生重氮化反应,加入吲哚后偶合成红色化合物。该化合物最大吸收波长为525nm;摩尔吸光系数为0.57×104L·mol-1·cm-1;线性范围0.053～24mg/L。该化合物至少稳定1h,焦化废水中存在的其它物质不干扰吲哚测定,样品的回收率为98.8%～102%。更多还原

【Abstract】 A novel spectrophtometric method for the determination of indole in coal coking wastewater has been proposed. In the sensitive and simple method, the sodium diphenylamine sulfonate was oxided to purple diphenylbenzidine sulfonic acid with the reaction of NaNO₂ in HCI medium, then the unstable oxidation product was further reacted with NaNO₂ to form a diazotized product , and that a red color was developed for the product on coupling to indole that was stable for at least 1 h. The absorption maximum was observed at 525 nm and the apparent molar absorptivity was 0.57×10 4 L·mol -1 ·cm -1 . Beer′s law was obeyed over the range of 0.053²4 mg/L. Other materials in coal xoking wastewater were free of interference on the determination of indole, and the recoveries were 98.8% ¹02%.更多还原