薄膜梯度扩散-分光光度法富集测量水中痕量Mo (VI)

建立了薄膜梯度扩散(DGT)- 硫氰酸钾(PT)分光光度法(DGT-PT法)富集测量水中痕量Mo (VI) 的分析方法。本研究先以聚季铵盐(PQAS)溶液为结合相的DGT技术 (PQAS DGT) 原位分离富集水中Mo (VI),再以PT分光光度法测定DGT结合相中Mo (VI)的含量,最后依据DGT方程计算水中Mo (VI)的浓度。DGT-PT法测得配制水中Mo ( VI) 的回收率为96.3% ~ 101.3%,相对标准偏差(RSD)为1.3% ~4.0%；测得工业废水中Mo (VI) 的浓度为27.13 ~ 121.79mg/L,加标回收率为96.0% ~ 101.6%。当采样时间为48h,PQAS DGT对水中Mo (VI) 富集近18倍,可显著降低分析方法的检测限,实现水中痕量Mo (VI) 的定量检测。

Determination of Mo (VI) in water by the diffusive gradients in thin-films techniquecombined with potassium thiocyanate spectrophotometry

Mo (VI) in water was pre-concentrated by the diffusive gradients in thin-films (DGT) technique with Poly (quaternary ammonium salt) (PQAS) as binding phase (PQAS DGT) and measured by potassium thiocyanate (PT) spectrophotometry. The recoveries of Mo (VI) in the synthetic solutions measured by the DGT-PT method were 96.3% ~ 101.3% with relative standard deviation (RSD) 1.3% ~ 4.0%. The concentration of Mo (VI) in industrial wastewaters measured by the DGT-PT method was 27.13 ~ 121.79 mg/L with recoveries of 96.0% ~ 101.5%. The enrichment factor of Mo (VI) pre-concentrated by PQAS DGT was 18 (deployment time 48h). Therefore, the DGT-PT method can be used to measure trace Mo (VI) in water.