Continuous micro flow monitoring method for total mercury at sub-ppb level in wastewater and other waters using cold vapor atomic absorption spectrometry

Abstract

An automated continuous monitoring method for total mercury at sub-ppb level based on cold vapor atomic-absorption-“continuous micro flow analysis“ is developed. The method uses continuous micro flow sample partial digestion, reduction and extraction in small bore tubes at low flow rates of reagents. Tin(II) chloride in sodium hydroxide solution was used as a reducing reagent. A mixed solution of potassium peroxodisulphate and copper(II) ion was used as oxidizing and catalytic reagent, respectively. The method was successfully applied to the completely continuous monitoring of total mercury in both wastewater and saline water without a heating digestion bath.