工业次氯酸钠溶液中氯酸钠含量的测定

Determination of sodium chlorate content in industrial sodium hypochlorite solution

利用次氯酸钠和氯酸钠的氧化能力不同,以双氧水消解次氯酸钠的影响,以硫酸中和次氯酸钠溶液中的氢氧化钠,以硫酸亚铁作还原剂,将试样中的氯酸钠还原,再用重铬酸钾标准溶液氧化过量的硫酸亚铁,从而测定工业次氯酸钠溶液中氯酸钠的准确浓度。方法简单可靠,测得的回收率高,检测极限(质量浓度)可达0.05g/L以下。

Sodium chlorate concentration in industrial sodium hypochlorite solution was determined correctly. The determination method comprised adding hydrogen peroxide solution to eliminate the influence of sodium hypochlorite on the basis of different oxidizing ability between sodium hypochlorite and sodium chlorate, neutralizing the sodium hydroxide contained in sodium hypochlorite solution with sulfuric acid, reducing the sodium chlorate contained in the sample with ferrous sulfate as reducing agent, and oxidizing the excessive ferrous sulfate with potassium dichromate standard solution. The method was simple and reliable, and the recovery rate was high. The determination limit could be as low as less than 0.05 g/L.