砷Ⅲ的流动注射化学发光分析方法研究

Study on Arsenic Ⅲ Determination by Flow Injection Chemiluminescence Method

酸性条件下高锰酸钾氧化AsⅢ产生化学发光,六偏磷酸钠与甲醛对该体系有显著的增强作用,据此建立了流动注射化学发光法测定水中砷的新方法.在优化的实验条件下,AsⅢ浓度在0·002～0·3μg/mL范围内与发光强度呈良好的线性关系,检出限为0·001μg/mL.对0·1μg/mLAsⅢ标准溶液进行11次平行测定,相对标准偏差为2·1%.将本法应用于水样中砷的测定,结果令人满意.

A new flow injection chemiluminescence method for the determination of arsenic（Ⅲ） is described, which is based on the phenomenon that sodium hexametaphosphate and formaldehyde will enhance the weak emission produced by potassium permanganate oxidation on arsenic（Ⅲ） in acidic media. In the optimum conditions, CL（chemiluminescence） intensities are proportional to concentrations of arsenic（Ⅲ） over the range 0.002-0. 3μg/mL with a detection limit of 0. 001μg/mL.The relative standard deviation （RSD） is 2. 1%for 0. 1μg/mL As（Ⅲ）（n=11）.The method has been applied to the determination of arsenic in water samples with satisfactory results.