酸雨及大气颗粒物中可溶性SO_4^(2-)的流动注射—比浊法测定

Determination of Water—Soluble Sulfate in Acid Rain and Atmospheric particles by Flow Injection—Turbidimetry

本文研究了在一定酸度下,以BaCl_2为沉淀剂,OP(聚乙二醇辛基苯基醚)为保护剂的比浊法测定酸雨及大气颗粒物中SO_4^(2-)含量的分析条件,选择的最佳体系为:BaCl_2·2H_2O(2％)—OP(5％)。SO_4^(2-)含量在0.6—7.2μg1ml范围内呈线性关系,回收率为95～105％,相对平均标准偏差小于2.6％。在此基础上与流动注射仪联用,提高了分析速度,改善了精密度。

Under the condition of using BaCl_2 as precipitant and OP as protective agent at pH 1.3—1.7, the exeprimental conditions for determining the concentration of SO_4^(2-) in acid rain and atmospheric particles by flow injection-turbidimetry were investigated. The optimum condition was found to be BaCl_2-2H_2O(2％)-OP(5％). Beer's Law is obeyed over the range of 0.6-7.2μg/ml for SO_4^(2-). The recovery results of sulfate in acid rain and atmospheric particle samples were between 95-105％, the relative standard deviation was less than 2.6％. This analytic method is successfully applied to detemination of SO_4^(2-) in acid rain and atmospheric particles.