流动注射法和气相色谱法检测生活饮用水中氰化物的比较  

Comparison of flow injection and gas chromatography in the determination of cyanide in drinking water

作　　者：张晶[1] 赵永信[1] 王军淋[1] 张念华[1] 冯靓[1] 方跃强[1] ZHANG Jing;ZHAO Yong-xin;WANG Jun-lin;ZHANG Nian-hua;FENG Liang;FANG Yue-qiang(Zhejiang Provincial Center for Disease Control and Prevention,Hangzhou,Zhejiang 310051,China)

机构地区：[1]浙江省疾病预防控制中心,浙江杭州310051

出　　处：《中国卫生检验杂志》2022年第23期2832-2835,共4页Chinese Journal of Health Laboratory Technology

摘　　要：目的 利用全自动流动注射分光光度法(异烟酸-巴比妥酸法)和顶空-气相色谱法分别测定水中总氰化物,并对2种方法进行分析比较。方法 流动注射法中,样品液在酸性介质中经高温紫外消解,氰化物以氰化氢的形式蒸馏出来后,被碱性溶液吸收,在弱酸性条件下与氯胺-T反应生成氯化氰,再与异烟酸反应,经水解生成的戊烯二醛与巴比妥酸缩合成蓝紫色燃料,600 nm处比色检测;顶空-气相色谱法中,酸性条件下,氯胺-T与水中总氰化物发生衍生反应生成氯化氰,顶空进样,气相色谱电子捕获检测器检测,外标法定量。结果 全自动流动注射法和顶空-气相色谱法,在一定浓度范围内,总氰化物浓度与峰面积的线性关系良好;流动注射法中,当添加浓度在4.0μg/L~20.0μg/L时,加标回收率为91.9%~93.9%,标准变异系数(RSD)<2.31%;顶空-气相色谱法中,在0.5μg/L~10.0μg/L的标准添加浓度内,加标回收率最低为89.5%,最高为94.9%。结论 2种方法测定水中总氰化物的灵敏度、精密度、准确度均符合国家《生活饮用水卫生标准》的检测要求。流动注射法适合大批量样品检测,分析速度更快,但试剂配制繁琐,费液产生较多。顶空-气相色谱法的检测灵敏度更高,所用试剂少,操作简单,环境污染小。Objective Total cyanide in water was determined by automatic flow injection spectrophotometry(isonicotinic acid-barbituric acid method) and headspace gas chromatography. The two methods were analyzed and compared. Methods In flow injection, sample solution was digested by high temperature ultraviolet in acid medium. Cyanide was distilled out in the form of hydrogen cyanide, absorbed by alkaline solution, and reacted with chloramine-T under weak acidic conditions to form cyanogen chloride. The reaction product of cyanogen chloride and isonicotinic acid was hydrolyzed to produce glutacondialdehyde, and then condensed with barbituric acid to form blue purple fuel. The colorimetric detection was carried out at 600 nm. In headspace gas chromatography, chloramine-T and total cyanide in water reacted with each other under acidic conditions to generate cyanogen chloride. After headspace injection, the samples were detected by gas chromatography with electron capture detector and quantified by external standard method. Results The linear relationships between total cyanide concentration and peak area in automatic flow injection and headspace gas chromatography were good in a certain concentration range. The range of spiked recoveries were 91.9%-93.9%, and the standard coefficient of variation(RSD) was less than 2.31% in the flow injection method when the added concentration was 4.0 μg/L-20.0 μg/L. The lowest recovery rate was 89.5% and the highest was 94.9% within the addition range from 0.5 μg/L to 10.0 μg/L in the headspace gas chromatography. Conclusion The sensitivity, precision and accuracy of the two methods for the determination of total cyanide in water meeted the detection requirements of the national sanitary standard for drinking water. The flow injection method was suitable for the detection of large quantities of samples, and the analysis speed was faster, but the reagent preparation was cumbersome, and there was more waste of liquid. Headspace gas chromatography had higher detection sensitivity, less rea

关 键 词：总氰化物检测 全自动流动注射分光光度法 顶空-气相色谱法 方法比较 

分 类 号：O657[理学—分析化学]