2012 Volume 61 Issue 11 Pages 931-938
This report describes a novel procedure allowing estimation of total PCB concentration in insulating oil by pattern analysis using selected peaks from gas chromatography with electron capture detection (GC/ECD). Two peaks for each of four Kanechlors (total of eight peaks) were selected on the basis of the signal intensity and orthogonality from the 97 distinct peaks corresponding to PCB congeners on the GC-ECD chromatogram. An algorithm is described to fit the measured eight peak pattern in the sample with a weighted sum of the eight peak pattern from each of the four Kanechlor mixtures. The weighted factors correspond to the concentration of individual Kanechlors in the sample, and their sum gives the total PCB concentration. Estimated concentrations of 14 transformer oil samples by the pattern analysis showed a good correlation with both HRGC-HRMS and the standard GC/ECD (analysis of all peaks from the chromatography) until 1.0 mg-PCB kg-oil−1 total PCBs.
