Research for Total Nitrogen Detection System Based on Electrochemical Method

Abstract

This paper presents a total nitrogen (TN) detection system based on electrochemical measurement. This system integrates a three-electrode system and a specially designed detection circuit. The dynamic response characteristic of the three-electrode system during TN electrochemical determination process was studied. The equivalent circuit of the three-electrode system was used to analyze factors of interference and signal instability. Through theoretical derivations and experimental proof, a time-domain model of signal response was established and two main factors, electric double layer capacitor and holding time, were put forward. Smooth and steady signal was achieved by optimizing these two main factors. Water sample of Taihu Lake was detected by this developed TN detection system with acceptable accuracy.