Correction techniques for iodine and bromine interferences in continuous flow aqueous mercury analysis.
An investigation of iodine and bromine interference on mercury measurements was carried out in aqueous samples by using continuous flow techniques. The role of acidity in the extent of the interference was also studied. A variety of methods for interference correction were tested, mostly aimed at changing the chemistry of the method to eliminate the offending complexes. The tests evaluated various methods of pH adjustment of the sample matrix prior to reduction with tin(II) chloride and the use of KBH(4) for reduction. On-line alkaline pH adjustment prior to tin(II) chloride reduction was found to be the most effective method for interference correction. Physical changes to the apparatus to extend the reaction time between the sample and SnCl(2) were also explored.
Babi
Diana
D
Tekran Inc, 330 Nantucket Boulevard, Toronto, Ontario, Canada M1P 2P4. db@tekran.com
Schaedlich
Frank H
FH
Schneeberger
Dan R
DR