流动注射分光光度法测定水的总硬度

Measuring total hardness of water by flow injection spectrophotometry

以铬黑T溶液为显色剂，在碱性条件下，利用流动注射技术及分光光度法实现了对水的总硬度的自动检测。对流动注射系统的反应条件进行优化，在波长520nm，载流液流速0．8mL／min、反应管长250cm、采样环25cm、显色剂浓度0．02％时得到最大吸光值。线性范围为5-500mg／L，回收率为96．8％-104．0。

Using eriochrome black T solution as the color reagent, a method of automatic detection of the total water hardness was realized through flow injection speetrophotomery under alkaline conditions. The reaction conditions of the flow injection system were optimized. The maximum absorbanee was reached when the wave length was 520 pan, the flow velocity was 0.8 mL/min, the length of the reaction pipe was 250 em, the length of the sampling ring was 25 era, and the concentration of the color reagent was 0.02%. The linear measuring range was 5 - 500 mg/L and the recovery rate was 96.8% - 104.0%.