【摘要】 建立了电位滴定法快速测定磷肥中水溶性磷含量的方法。用蒸馏水溶解磷肥中的水溶性磷,通过硝酸钡和阳离子交换树脂除去干扰离子,用六次甲基四胺-硝酸缓冲溶液控制试液的酸度(pH=5.4),在乙醇体系中,用一定浓度的硝酸铅标准溶液进行电位滴定,用二阶微分法确定硝酸铅标准溶液的滴定终点体积。方法的RSD为0.66％～0.97％,回收率为100.00％～100.10％。更多还原

【Abstract】 The determination method of the water-soluble phosphorus in the phosphatic fertilizers is set up by potentiometric titration. The water-soluble phosphorus in the phosphatic fertilizers is dissolved with the distilled water. The interference ion is eliminated through the ion-exchange resin and barium nitrate. The reagent acidity (pH = 5.4) is controlled by hexamine-nitric acid. The potentimetric titration is carried out with lead nitrate standard solution. The end point of titration is determined with the second order differential titration. RSD of the method is 0.66% - 0.97% and the recovery is 100.00% - 100. 10% .更多还原