SOLID-PHASE EXTRACTION AND CAPILLARY GC-ECD ANALYSIS OF POLYCHLORINATED DIBENZO-P-DIOXINS IN CHLORINATED PHENOLS

Studies were carried out to establish whether the solid phase extracti on (s.p.e.) was a suitable technique for preconcentration and isolatio n of polychlorinated dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) from chlorophenol samples. Because of the low concentration o f these compounds in the investigated polychlorophenol samples, method s for selective enrichment and sensitive detection are desirable. Prec oncentration of PCDDs from chlorophenate alkaline water solution by a factor of 20 was achieved in one step on three different s.p.e.-ODS, s .p.e.-phenyl and s.p.e.-octyl phases. The best recovery of PCDDs was f ound for and ODS phase, where chlorophenate water solution was adjuste d to pH = 12. It was shown that average PCDDs recoveries obtained usin g s.p.e. technique for s.p.e.-ODS and s.p.e.-phenyl phases were simila r to the ones obtained by liquid/liquid extraction but the time needed for isolation of PCDDs isomers from chlorophenol samples was reduced by factor of four.