海水中臭氧总残留氧化物三种检测方法的比较研究

A comparative study of three methods for detecting total residual oxidants in seawater

对臭氧总残留氧化物（TRO）常用3种检测方法（碘化钾-N,N-二乙基-1,4-苯二胺（KI-DPD）分光光度法、硼酸碘化钾（H3BO3-KI）比色法、靛蓝二磺酸钠（IDS）分光光度法）进行了比较研究。结果表明：在0～0.5 mg/L的TRO浓度范围内,KI-DPD分光光度法和H3BO3-KI比色法线性关系良好,检出限分别为0.040 mg/L和0.034 mg/L,并且这两种测定方法的准确性和重复性较佳,相对标准偏差（RSD）均小于5.0%,低于传统碘量法;而IDS分光光度法只有在高浓度臭氧海水样品（0.6～1.2 mg/L）检测时,RSD才小于5.0%,且测定浓度明显低于另外两种方法。故对于海水养殖水体中的TRO检测,KI-DPD分光光度法和H3BO3-KI比色法均准确有效,并且H3BO3-KI比色法在检测操作上更为简便快捷。

In this study, three relevant methods to detect total residual oxidants（TRO） in seawater were compared; the potassium iodide-N, N-diethyl-p-phenylene diamine（KI-DPD）spectrophotometric method, the boric acid potassium iodide（H3BO3-KI） colorimetry method, and the indigo disulfonic acid sodium（IDS）spectrophotometric method. The results showed that when TRO were in the range of 0~0.5mg/L, KI-DPD and H3BO3-KI presented good linear relationships and their detection limits were 0.040 mg/L and 0.034 mg/L, respectively. The relative standard deviation（RSD）of these two methods was 5.0%, which was less than the traditional iodine quantity method. However, the RSD of IDS was 5.0% only when the TRO concentration was in the rangeof 0.6--1.2mg/L. Furthermore, the corresponding IDS concentration was significantly lower thanthat in the other two methods. Therefore, for TRO detection in seawater, KI-DPD and H3BO3-KI are suggested. Moreover, H3BO3-KI is easier to operate.