Composition of chloronaphthalene congeners in technical chloronaphthalene formulations of the Halowax series

Normalised pattern (DB-5 capillary column) of polychlorinated naphthalenes (PCNs; CNs) for all seven technical Halowax formulations and mass percent c ontribution (CN %) for an equivalent mixture of Halowax 1031, 1000, 1001, 1 099, 1013, 1014 and 1051 (Equi-Halowax) is presented. 2,3-DiCN (PCN no. 10) , 1,6,7- and 2,3,6-TrCNs (PCNs nos 25 and 26) and probably also 1,3,5-TrCN (PCN no. 19), 1,3,6,7-, 1,2,3,6- and 1,2,3,8-TeCN (PCNs nos. 44, 29 and 31) , and 1,2,3,6,7,8-HxCN (PCN no. 70) were absent in commercial PCNs formulat ions. The congeners such as 1,2,3-TrCN (PCN no. 13), 1,3,8-TrCN (PCN no. 22 ) and 1,2,3,6,7-PeCN (PCN no. 54) were present in the mixtures at very low concentrations. The congeners most abundant in Halowax mixtures are usually chlorinated at alpha-positions (1, 4, 5, 8 - positions) of the naphthalene nuclei. Because of some unresolved peaks observed on the chromatograms due to insufficient separation power of DB-5, and also of many other liquid ph ases used in capillary gas chromatographic separation of PCNs even when mas s spectrometric detection was used, a perfect isomer and congener compositi on of PCN mixtures still has to be elucidated.