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Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: Sergevna on May 10, 2006, 04:31:37 AM

Title: Electro-Chemical Gas Analyzer
Post by: Sergevna on May 10, 2006, 04:31:37 AM
Hi, my name is Anna. In my work I use electro-chemical gas analyzer. I think it doesn't work well (some problems inside). To find the reason I've tried to understand the principles of work of this device. But there is not much informaton about it. It's known that three-electrode electrochemical cell is used to define the gas concentration. But there is no information about electrode materials, electrolyte, mechanism of concentration measurement ( maybe voltammetry or potentiometry).
maybe someone has useful information about this topic, thanks

P.S. name of device: "GreenLine Mk2", Portable flue gas laboratory (Eurotron),  Electro-Chemical Gas Analyzer
Title: Re: Electro-Chemical Gas Analyzer
Post by: Donaldson Tan on May 10, 2006, 12:15:28 PM
The electro-chemical gas analyser is designed to measure the concentration of flue gas constituents (O2, CO, NO, NO2, SO2, H2S). For each flue gas constituent, there are 2-3 electrodes which are specifically made to measure only that particular flue constituent by uising an electrolytic matrix which which only reacts with that flue constituent in interest. The redox reaction occuring on the surface of the electrodes causes the potential to fall and rise. The fall and rise of the potential is correlated to the concentration of the flue gas constituent. However, the measurements are subjected to disturbances by fluctuation in pressure and temperature.
Title: Re: Electro-Chemical Gas Analyzer
Post by: Donaldson Tan on May 12, 2006, 11:18:57 AM
The Nerst Equation is used to relate the electroide potential to the concentration.

I reckon the electrolytic matrix and and electrode material is proprietary information.

Maybe you can carry out a chemical analysis to find out.