腐植酸钠中钠含量的电位法测定研究

Potentiometric Determination of Sodium Content in Sodium Humate

为了方便准确测定腐植酸钠中的钠含量,采用Na+选择电极为工作电极的电位法对Na+进行测定。以pH为9的0.06 mol/L的盐酸三乙醇胺缓冲溶液为底液,通过标准曲线法测得该测定方法标准曲线的线性回归方程为E=53.1780lgc+83.8768,线性范围为1.0×10-3~23 mg/mL,测量适宜pH范围为8~10。平均加标回收率为100%,相对标准偏差0.077%。该测定方法线性范围宽,重现性好,准确度高,检测成本低,易于应用,是测定腐植酸钠盐中钠含量的有效方法。

To determine sodium content in sodium humate conveniently and accurately,sodium ion was determined by potentiometry using sodium ion selective electrode as working electrode,with 0.06 mol/L triethanolamine hydrochloride buffer solution(pH=9)as the base solution.The linear regression equation of the standard curve measured by standard curve method was E=53.1780 lgc+83.8768,and the linear range was 1.0×10-3~23 mg/mL,the suitable pH range was 8~10,the average recovery was 100%and the relative standard deviation was 0.077%.The method was effective for the determination of sodium in humate because of its wide linear range,good reproducibility,high accuracy,low detection cost and easy application.