Rapid in situ determination of ClO2 in drinking water by improved solid DPD spectrophotometry

Qianqian Zhang,Tianli Hao,Ke Zeng,Lijun Jia

doi:10.1051/e3sconf/202125202063

Abstract

This research aims to realize the rapid detection of ClO2 content in drinking water by adopting improved solid DPD. This method is fast and convenient with low cost and less waste liquid. The results show that this method has good precision and sensitivity. The linear correlation coefficients of the cubic regression equation were all greater than 0.999. The detection limit of the method was 0.002mg/L ClO2. The relative standard deviations (RSD) of seven parallel tests were between 1.37% and 8.87%, and the relative errors were small. The recovery rate was 96.67~110%. The method could be used for the direct determination of water samples with a mass concentration of 0.02mg/L~2.00mg/L in drinking water after ClO2 disinfection.

Highlights

According to the statistics of the World Health Organization(WHO), 80% of human diseases are caused by drinking unclean water [1].In China, less than 11% of people drink water satisfying China's health standards, while up to 65% drink water which is muddy, bitter, polluted by industry or infectious diseases
The safety of drinking water quality is a major livelihood issue related to thousands of households, and disinfection technology is crucial to ensure the safety of drinking water microorganism [2、3].The main disinfectants used in drinking water include chlorine dioxide (ClO2), liquid chlorine, free chlorine preparation and ozone
ClO2 disinfectant is listed as A1 safe disinfectant by WHO because of its non-carcinogenicity, non-teratogenicity and non-mutagenicity [4].At the same time, it has advantages of strong oxidation and sterilization ability, a wide range of water quality and pH application

Summary

Introduction

According to the statistics of the World Health Organization(WHO), 80% of human diseases are caused by drinking unclean water [1].In China, less than 11% of people drink water satisfying China's health standards, while up to 65% drink water which is muddy, bitter, polluted by industry or infectious diseases. The safety of drinking water quality is a major livelihood issue related to thousands of households, and disinfection technology is crucial to ensure the safety of drinking water microorganism [2、3].The main disinfectants used in drinking water include chlorine dioxide (ClO2), liquid chlorine, free chlorine preparation and ozone. ClO2 disinfectant is listed as A1 safe disinfectant by WHO because of its non-carcinogenicity, non-teratogenicity and non-mutagenicity [4].At the same time, it has advantages of strong oxidation and sterilization ability, a wide range of water quality and pH application. ClO2 disinfectant has been substituted by liquid chlorine gradually in China [5]. ClO2 does not produce halogenated disinfection by-products during the disinfecting of drinking water, it may produce chlorite, an inorganic by-product harmful to human body[ 6 ]. It is clearly stipulated that the limit of ClO2 in the factory water is 0.8mg /L in the GB5749-2006 "drinking water hygiene standards"[7].

Objectives

Methods

Results