PREPARATIVE FRACTIONATION OF A COMMERCIAL PCB PRODUCT

A commercial PCB product, Clophen A 50 (3 g) was separated into four fractions containing; I: PCB congeners with two or more chlorines in the ortho-positions of the biphenyl, II: 1-ortho substituted PCB, III: O-ortho substituted (coplanar) PCB, and IV: polychlorinated naphthalenes and polychlorinated dibenzofurans. The separation was performed by taking advantage of the difference in retention on charcoal of PCB congeners with varying degree of planarity. A combination of columns containing charcoal, charcoal mixed with celite and aluminium oxide, respectively, were used. An extractor (Wallenberg extractor) was developed which made it possible to efficiently extract compounds strongly adsorbed on the charcoal in the columns.