论文部分内容阅读
目的探讨用银离于交换树脂去除食盐溶液中高浓度Cl干扰及用离子色谱法测定食盐中的微量F-和SO42-的适宜条件。方法用硝酸银溶液和阳离子树脂制备银离子交换树脂,将食盐溶液与银离子交换树脂混合,充分搅拌10 min后过滤,离子色谱法测定溶液中微量F-和SO42-。结果 F-和SO42-的标准曲线的相关系数(r)均大于0.999 0,食盐中F-和SO4 2-的最低检出浓度分别为0.66、3.3 mg/kg(取样量为5.0 g),相对标准偏差均小于1.0%,实际样品的加标回收率为90.8%～102.1%。结论该法灵敏度高,精密度好,回收率高,适合食盐中微量F-和SO4 2-的测定。
OBJECTIVE To investigate the optimum conditions for the determination of trace F- and SO42- in table salt by ion exchange chromatography with silver ion exchange resin to remove high concentration Cl from salt solution. Methods Silver ion exchange resin was prepared from silver nitrate solution and cationic resin. The salt solution was mixed with silver ion exchange resin, stirred for 10 min and then filtered. Trace F- and SO42- in solution were determined by ion chromatography. Results The correlation coefficients (r) of the standard curves of F- and SO42- were both greater than 0.999 0. The lowest detectable concentrations of F- and SO42 2- in the salt were 0.66 and 3.3 mg / kg respectively (the sample volume was 5.0 g) The standard deviations were less than 1.0%. The spiked recoveries of real samples ranged from 90.8% to 102.1%. Conclusion The method has high sensitivity, good precision and high recovery, which is suitable for the determination of trace F- and SO42- in salt.