便携式分光光度计法快速测定水中砷方法研究

Research on Rapid Determination of Arsenic in Water Samples by Using Portable Spectrophotometers

通过研究各仪器性能指标以及测定实际水质样品，对3种便携式分光光度计快速测定水中砷的方法进行了优化和比对研究。结果表明，ZZW－Ⅱ测试仪快速测定水中砷的方法检出限（0．2 mg／L）高于 JH 916检测仪和 PORS －15 V 光谱仪的方法检出限（0．008和0．009 mg／L），在突发性环境污染事故应急监测中，JH 916检测仪和 PORS －15 V 光谱仪具有相对较高的灵敏度。ZZW－Ⅱ测试仪和 JH 916检测仪快速测定水中砷的方法精密度相近，其测定结果相对标准偏差均未超过5．7％（n＝6），PORS －15 V 光谱仪快速测定水中砷的方法精密度稍差，其相对标准偏差最大值为17％。测定实际样品时，加标回收率分别为110％～126％（ZZW－Ⅱ测试仪），63％～108％（PORS －15 V 光谱仪），78％～101％（JH 916检测仪）。3种便携式分光光度计与实验室分析方法相比，测定结果精密度均存在显著性差异，测定结果相对偏差亦较大，相对偏差最大值分别为－19．0％（ZZW－Ⅱ测试仪），17．0％（PORS －15 V 光谱仪），－15．0％（JH 916检测仪）。

Methods of rapid determination of arsenic in water samples by using three kinds of portable spectrophotometer were opti-mized and the contrast research on these methods was carried out in this paper.By testing the performance indexes of different instru-mental methods and determining the arsenic in actual water samples,the advantages of different portable spectrophotometers were com-pared.The research result would be able to provide a reference for choosing the suitable monitoring instruments used in sudden envi-ronmental pollution accident.The experimental results showed：the detection limit of ZZW-Ⅱportable spectrophotometer （0.2 mg/L） was higher than that of JH 916 portable spectrophotometer （0.008mg/L）and PORS-15 V portable spectrophotometer （0.009 mg/L）, it meant that the PORS-15 V portable spectrophotometer and JH 916 portable spectrophotometer had higher sensitivity in monitoring sudden environmental pollution accident than ZZW-Ⅱportable spectrophotometer.The method precision of JH 916 portable spectropho-tometer and ZZW-Ⅱportable spectrophotometer were similar and the RSDs（relative standard deviation）were all below 5.7% （n=6）. The method precision of PORS-15 V portable spectrophotometer was not better than the other two spectrophotometers,the maximal RSD was 17%.The recoveries were 1 10%～126%（ZZW-Ⅱportable spectrophotometer）,63%～108%（PORS-15 V portable spectrophotom-eter）,78%～101%（JH 916 portable spectrophotometer）for the actual water samples.There was significant difference between the pre-cision of standard method in lab and the precision of the three kinds of portable spectrophotometer,the maximal relative deviations were-19.0%（ZZW-Ⅱportable spectrophotometer）,17.0%（PORS-15 V portable spectrophotometer）,-15.0%（JH 916 portable spectroph-otometer）.