To remove main disturbing ion, chlorine ion in the COD potassium dichromate reflux method, silver sulfate replaces mercury sulfate as a screening agent.
对cod重铬酸钾回流法中的主要干扰离子，氯化物的消除，选择了用硫酸银代替硫酸汞做掩蔽剂。
2
The method shows the advantages of simple operation, less pollution, high analytical speed, better accuracy and precision over the traditional potassium dichromate oxidation method.
与重铬酸钾氧化法的结果相比，微波消化法具有操作简单、污染小、快速准确的优点。
3
In view of the detrimental effect of mercury and chromium in determination of iron by means of dichromate titration, a new method was proposed containing no mercury and chromium.