基于酸性条件下硅酸盐与钼酸铵反应生成硅钼黄而后被还原成硅钼蓝的原理,利用流动注射分析技术,建立了快速测定海水中活性硅酸盐的分析方法.在优化的条件下,方法检测限为0.5μMOl·l-1,线性范围为2.5~110.0μMOl·l-1,实际海水的加标回收率为103.6%~109.3%,同一水样连续测3次仅需4.5MIn.测定硅浓度11.7μMOl·l-1的南海海水样,相对标准偏差(rSd)为1.6%(n=12).该方法具有简单、快速、水样消耗少、盐度高于14即不干扰测定等优点,成功地用于厦门西港海水中活性硅酸盐浓度的测定.A new flow injection analysis method for rapid determination of soluble reactive silicate in seawater is established based on the reaction of silicate with ammonium molybdate to form a yellow silicomolybdate complex,and further reduction to silicomolybdenum blue by ascorbic acid.Under the optimum conditions,the detection limit was 0.5 μmol · L-1;the linear and recovery ranges for real seawater samples were 2.5--110.0 μmol · L-1 and 103.6%--109.3%,respectively.Only 4.5 min was needed to analyze one sample in triplicate.The relative standard deviation(RSD) was 1.6%(n=12) for seawater samples obtained from the South China Sea with a silicate concentration of 11.7 mol · L-1.The proposed method is simple,fast,requires little sample,and showed no interference from salinity(>14).The method was successfully applied to measure the soluble reactive silicate in seawater samples in Xiamen's Western Harbor.国家高技术研究发展计划资助项目(No.2007AA061501)---
