用于水体中COD检测的氯离子试纸的研制

Study on Chloride Test Paper for COD Measurement of Water

在重铬酸钾法测定水中化学需氧量(COD)过程中,对氯离子浓度的粗判至关重要。常规的滴定法和现有的氯离子试纸存在一定的缺陷,因此急需开发一种服务于COD检测的高效、简便、廉价的氯离子试纸。基于此研制了一种基于铬酸银的半定量氯离子试纸。该试纸对三个浓度梯度的氯离子溶液测定的相对标准偏差为1.9%~4.6%。该试纸制备廉价易行,使用简便可靠,2 min即可得到结果,适用于澄清透明、中性或酸性(pH=2~8)的水样中氯离子浓度的粗判。

During the measurement of chemical oxygen demand(COD)by dichromate method,it is of vital importance assessing the concentration of chloride iron.As both titration method and commercial Cl-test paper have certain defects,it is crucial developing an efficient,convenient and low-cost Cl-test paper for COD measurement.A novel kind of semiquantitative Cl-test paper based on silver chromate was developed.Its RSD during measurement of water samples of three concentration was evaluated as 1.9%~4.6%.The test paper was proved to be low-cost,simple,handy,efficient,and suitable for rough evaluation of chloride within 2 min for clear water samples at the range of pH=2~8.