STATIONARY-PHASE FOR THE DETERMINATION OF FLUORIDE AND OTHER INORGANIC ANIONS

A pellicular anion-exchange column was developed for the determination of inorganic anions including fluoride and oxyhalides such as chlorit e, chlorate and bromate. Compared with conventional latex-agglomerated resins, the new anion exchanger allows the retention of fluoride well out of the water dip with elution of sulfate in less than 15 min usin g a carbonate-hydrogencarbonate eluent under isocratic conditions. Bec ause the ethylvinylbenzene-divinylbenzene substrate is highly cross-li nked, the new separator is solvent compatible, thus allowing the use o f organic solvents to alter the selectivity of the separation, and als o to remove organic contaminants from the column. The separation chara cteristics of this column are presented and various applications are d iscussed.