【摘要】 阐述了一种基于碱性条件下,采用还原液将硝酸盐还原为亚硝酸盐,从而实现淡水中硝酸盐的还原液-流动注射分光光度检测方法,通过优化实验确定了最优分析条件。硝酸盐浓度在50～2000μg/L范围内与峰高呈良好的线性关系,方法检出限3.5μg/L,相对标准偏差0.90%(n=15,500μg/L)。方法应用于环境水样中硝酸盐的检测,加标回收率为95.0%～100.2%。该方法避免了镉还原柱再生处理,简化了操作,易于实现无人值守式的在线自动监测。更多还原

【Abstract】 Under alkaline conditions,nitrate is reduced to nitrite by the action of reducing agent with the catalytic action of copper ion.According to the above reaction,this paper proposes a simple,accurate,sensitive and selective reducing agent-flow injection spectrophotometric method for rapid determination of nitrate in freshwater.The optimum analytical conditions were chosen through optimizing experiments.Response to nitrate was linear in the range of 5～2000μg/L,the detection limit was 3.5μg/L,the relative standard deviation(RSD) was 0.90% for 500μg/L nitrate(n=15).The proposed method was applied to the determination of nitrate in freshwater,the analytical results were satisfactory,and the recoveries were between 95.0% and 100.2%.The method avoided the regeneration treatment of reduction column due to reducing agent instead of cadmium reduction column,the operation was simplified.It is easy to realize the unattended on-line automatic monitoring.更多还原