Determination of Drinking Water Total Hardness Using Automatic Potentiometric Titration in Two Modes / 环境与健康杂志

Objective To establish a method for determination of total hardness in drinking water by using automatic potentiometric titrator.Methods Dynamic equivalence point titration(DET)and monotonic equivalence point titration(MET)mode was used to determine the high total hardness and low total hardness of drinking water samples respectively.Results Used DET mode to determine the high total hardness,the relative standard deviation(RSD)was 0.69%～1.72% and the recovery rate was 101.5%～102.2%.Used MET mode to determine the low total hardness,RSD was 3.49%～4.00% and the recovery rate was 95.8%- 103.6%.Conclusion This method is rapid,simple,accurate,precise and applicable to the determination of total hardness in drinking water in low and high levels.