By-side impurities in chloronaphthalene mixtures of the Halowax series: all 12 chlorobenzenes.

Total chlorobenzene content of the Halowax mixtures ranged from 1100 to 9800 ng/g. A lower chlorinated Halowax 1031 and 1000 were a several times more contaminated with chlorobenzenes than higher chlorinated Halowax 1001, 1099, 1013, 1014, or 1051. Depending on the type of the Halowax mixture the most contributing amongst of chlorobenzene homologue groups were di-, tetra-, penta-, and hexa-CBz. A dominance and specific profile of 1,4-DiCBz, PeCBz, and HCBz were characteristic to Halowax 1001, 1099, 1013, 1014, and 1051, while for other formulation the CBzs profile varied, and 1,2,3,4-TeCBz (Halowax 1031) and 1,4-DiCBz (Halowax 1000) predominated. A steric hindrance effect seems to direct a preferential by-side formation of 1,4-DiCBz and further also of PeCBz and HCBz due to relatively elevated temperature as well as duration time of synthesis for five most chlorinated (49-70 Cl%) chloronaphthalene Halowax formulations.

By-side impurities in chloronaphthalene mixtures of the Halowax series: all 19 chlorophenols.

All seven Halowax formulations examined were contaminated with chlorophenols (CPhs). The total CPhs content of the CN mixtures ranged from 1050 to 34,200 ng/g. The absolute concentration of CPhs decreased with an increase of degree of chlorination (% Cl) of the Halowax 1031 (27%), 1000 (35%), 1001 (49%), and 1099 (51%), respectively, but remained relatively constant for higher chlorinated Halowax 1099 (51%), 1013 (54%), 1014 (59%), and 1051 (70%). 2,4,6-TrCPh and 2,4-DiCPh did contaminated all seven Halowax formulations and PeCPh remained undetected (<90 ng/g) only in Halowax 1099, while less frequently occurred 2,6-DiCPh and followed by 3-/4-MoCPh, 2,5-DiCPh, 2-MoCPh, 2,3-DiCPh, and 2,3,4,6-TeCPh. The CPh congeners such as 3,4-DiCPh, 3,5-DiCPh, 2,3,4-TrCPh, 2,3,5-TrCPh, 2,3,6-TrCPh, 2,4,5-TrCPh, 3,4,5-TrCPh, 2,3,4,5-TeCPh, and 2,3,5,6-TeCPh were undetected in any of the Halowax formulation examined. The profile (%) of higher chlorinated CPh homologues like PeCPh in the Halowaxes followed somehow a degree of chlorination (Cl %) of the parent mixture, i.e., increased from 14, 22, 43, 55, 52 to 80%, respectively, but exception was free of PeCPh the Halowax 1099. And contrary, for a lower chlorinated DiCPhs and TrCPhs their relative proportions decreased but again an exception was Halowax 1099. The fingerprint profiles of 2,4,6-TrCPh, 2,4-DiCPh, and PeCPh, which were usually the most abundant congeners varied and were less consisted when compared to the CPh homologue group profiles, and also more depended on the type of technical Halowax mixture. Due to absence of 2,4,5-TrCPh but presence of 2,4-DiCPh, 2,6-DiCPh, 2,4,6-TrCPh, and PeCPh, which, respectively, are indicative congeners for CPhs obtained by alkaline hydrolysis of chlorobenzenes or phenol chlorination using gaseous chlorine, just co-occurrence of phenol impurity in technical naphthalene is suggested as a solely source of CPhs in the Halowax mixtures.