Fast and stable real time monitoring of gaseous mercury in its catalytic oxidation using a fully modified cold-vapor atomic absorption mercury analyzer

Abstract

A commercially-available cold-vapor atomic absorption mercury analyzer had many difficulties in monitoring real-time gaseous mercury (Hg0) in its oxidation over a V2O5/TiO2-based catalyst under conditions additionally containing HCl, NO and NH3. Thus we made extensive modifications to the original analyzer so that this is suitable for fast and stable real-time Hg0 detections even at low sample flow rates as well as at the harsh conditions. Our fully modified analyzer gave Hg0 signals very similar to those based upon the factory-certified permeation rate of the mercury permeation tube. Gaseous Hg0 could react, only to a small extent, with HCl over a quartz powder and the measured Hg0 oxidation activity was almost associated with the catalyst depending on concentrations of HCl fed to gas streams with NO and NH3. This study can offer useful solutions to academic and industrial research groups to attempt real-time Hg0 measurements at such chosen conditions.