氢化物发生–原子荧光光谱法同时测定锌锭中砷和锑

建立用氢化物发生–原子荧光光度计同时测定锌锭样品中砷和锑含量的方法。采用硝酸一次溶样,加入酒石酸防止锑水解。加入硫脲–抗坏血酸混合溶液作为还原剂和掩蔽剂,消除干扰元素的影响,对实验条件进行了优化。砷和锑的负高压分别为220,200 V,灯电流分别为80,60 mA,还原剂为1%硼氢化钾溶液(含0.5%KOH),载流为10%盐酸溶液,还原时间为30 min。测定砷的线性范围为0~80 ng/mL,相关系数r=0.999 8,检出限为0.35μg/L,测定结果的相对标准偏差为3.18%(n=11);测定锑的线性范围为0~80 ng/mL,相关系数r=0.999 6,检出限为0.42μg/L,测定结果的相对标准偏差为4.32%(n=11),砷和锑的加标回收率在97.46%~100.30%之间。用该方法对标准样品进行测定,测定结果与标准值相符。该方法基体干扰少,灵敏度高,适合于锌锭中砷和锑的日常测定。

Simultaneous Determination of Arsenic and Antimony in Zinc Ingot by Hydride-Atomic Fluorescence Spectrophotometry

The method for the simultaneous determination of arsenic and antimony in zinc ingot sample by hydride atomicfluorescence spectrophotometry was established. Nitric acid digestion was used, tartaric acid was added to prevent hydrolysis. Thiourea-ascorbic acid was usedas reducing agent and masking agent to eliminate interference effects. Experimental conditions were optimized,arsenic and antimony negative high voltage were 220, 200 V, respectively, lamp current were 80, 60 mA, respectively, reducing agent was 1% potassium borohydride solution (include 0.5% KOH),current carrying was 10% hydrochloric acid solution,and the reduction time was 30 min. The linear range of arsenic was 0-80 ng/mL with the correlation coefficient (r) of 0.9998,the detection limit was 0.35μg/L,and the relative standard deviation was 3.18%(n=11). The linear range of antimony was 0-80 ng/mL with the correlation coefficient (r)of 0.9996,the detection limit was 0.42μg/L, and the relative standard deviation was 4.32%(n=11). The standard addition recoveries of arsenic and antimony werein the range of 97.46%-100.30%. The method was used to determine the standard sample, the detection result was consistent with the standard value. This method has high sensitivity, less matrix interference, it is suitable for the routine determination of arsenic and antimony in zinc ingot sample.