MODIFIED SILICA AS A STATIONARY-PHASE FOR ION CHROMATOGRAPHY

The possibility of the rapid preparation of agglomerated anion exchangers was demonstrated on a reversed-phase silica support with the polymeric agents poly(N-ethyl-4-vinylpyridinium bromide), poly(dimethyldiallylammonium chloride), poly(hexamethyleneguanidinium hydrochloride) and 2,5-ionene as modifiers. A 90-min sorbent preparation and column packing allowed an efficiency of more than 10000 theoretical plates per metre to be obtained for 10-mu m spherical beads, The polymeric agents showed different selectivity, stability and capacity for the resulting anion exchangers (owing to changes in the structure and the density of functional groups in the polymer chain). The sorbents were used for the simultaneous determination of weakly and strongly retained anions and some heavy metals with EDTA solutions as eluent.