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The production, use and toxicity of Polychlorinated biphenyls (PCBs) has been discussed in detail and increasing concern has been shown by the scientific community and by the public about the effectiveness of thermal incineration as an environmentally satisfactory means of destroying polychlorinated biphenyls. Therefore, a greater need for alternative, more efficient, low energy processes such as catalytic combustion, has been discussed. This paper is part of research to investigate the catalytic combustion of Aroclor 1242 in a packed bed reactor using chromia on an alumina support and other oxidation catalysts. It was essential for these studies to be able to determine the PCB destruction efficiencies of the catalytic processes examined. The high efficiency of capillary GC columns permits the resolution of an Aroclor into a chromatogram consisting mainly of individual PCB congeners. The chromatogram may typically contain 50-150 peaks. Quantification requires each peak to be identified and individual response factors assigned before the amount of each congener present may be calculated. Response factors vary and the high cost of purchasing all individual PCB standards was prohibitive. A commonly adopted alternative method is to measure only the 6 or 7 individual PCB congeners available as a commercial mixture and convert themore » answer into a value for an Aroclor, not an accurate measure of the destruction efficiency of PCBs. This paper describes a simple quantitative HPLC method that measures all PCBs as a single peak. 14 refs., 3 figs., 1 tab.« less

The determination of polychlorinated biphenyls (PCBs) in environmental samples presents the analyst with many problems. PCBs occur as complex mixtures in the environment at variable concentrations ranging from the low ppb to the ppm level. Most sample extracts need to be subjected to an extensive cleanup procedure prior to GC analysis. In order to overcome some of these problems, perchlorination of the PCBs has been used; this gives rise to one GC peak (decachlorobiphenyl) which is well removed from most interfering peaks, but this technique has been found to be qualitatively and quantitatively unreliable. Dechlorination has also been proposed. A nickel boride dechlorination method was employed whereby a precipitate of nickel boride is produced in situ.