Development of an automated on-line electrochemical chlorite ion sensor

Abstract

A sensor system for the automatic, in-line, determination of chlorite ion is reported. Electroanalytical measurements were performed in electrolyte-free liquids by using an electrochemical probe (EC), which enables in-line detection in high-resistance media such as disinfected water. Cyclic voltammetry scan rate studies suggest that the current arising from the oxidation of chlorite ion at an EC probe is mass-transfer limited. By coupling FIA with an EC probe amperometric cell, automated analysis was achieved. This sensor is intended to fulfill the daily monitoring requirements of the EPA DBP regulations for chlorite ion. Detection limits of 0.02-0.13 mg/L were attained, which is about one order of magnitude below the MRDL. The sensor showed no faradaic signal for perchlorate, chlorate, or nitrate. The lifetime and stability of the sensor were investigated by measuring calibration curves over time under constant-flow conditions. Detection limits of <0.1 mg/L were repeatedly achieved over a period of three weeks.

Tetiklenmiş Floresans Özelliğe Sahip Bir Kimyasal Sensör Olarak Benzotiyazol Grubu Taşıyan Kaliksaren Sentezi

“…The related process has been reviewed and all disinfection by-products (DBPs) have been identified in line with the studies in the literature [5][6][7]. In this sense, the formation of chlorite ion (ClO2‾) has been an undesirable situation because of its potential of causing hemolytic anemia and adverse nervous system effects (lowered auditory startle amplitude, decreased exploratory activity) along with decreased absolute brain weight and altered liver weights [8,9]. However, disinfection has been essential for water sources safeguard, the health risks from disinfectants and disinfection by-products have been much less than the risks from consuming water that has not been disinfected [10].…”