Formation of PCDD/F during thermal treatment of lignite

Investigations whether lignite is a source for polychlorinated dibenzodioxins and -furans (PCDD/F) or not were carried out. Considering the special situation at former opencast mines in East Germany, lignites from different locations at the east and the west side of the river Elbe were chosen. Weathering processes were simulated in our laboratory. Some of the untreated lignites already contained PCDD/F at ppt level. Treatment with wet air at 300 degrees C led to up to six times higher PCDD/F concentrations. Degree of weathering influences PCDD/F formation. CuCl2, was found to act as a catalyst for PCDD/F formation using lignite as carbon source. (C) 1999 Elsevier Science B.V. All rights reserved.