茚三酮比色法测定水中微量氨含量

Determination of Trace Ammonia Content in Water by Ninhydrin Colorimetry

在一定酸度和温度条件下,氨能与茚三酮和还原性茚三酮反应生成蓝紫色化合物。依据此原理,通过系列条件试验,确定了显色剂、还原剂、缓冲液的加入量和显色时间,建立了不使用剧毒试剂(氯化高汞)测定水中微量氨含量的比色分析法。通过标准曲线试验、精密度试验、回收率试验和对比试验,验证了该测定方法准确、可靠。

Under fixed acidity and temperature conditions, ammonia can react with ninhydrin and reductive ninhydrin to give a bluish violet compound. Based on this principle and through a series of conditional tests, the developer, reducer, buffering solution additions and development time are ascertained, and the colorimetric analytical process is established to determine the trace ammonia content in water without the use of highly toxic reagent （mercuric chloride）. The determination method is verified to be accurate and reliable by the use of the standard curve, precision, percent recovery and contrast tests.