Iron chloride catalysed PCDD/F-formation: Experiments and PCDD/F-signatures

•De novo PCDD/F-formation from model fly ash, incorporating FeCl3.•The influence of temperature is studied in a wide range (250-550 °C).•The effect of oxygen (0, 5, 10, 20 vol %) is analysed at 350 °C.•An isomer analysis is produced for all tests.•2,3,7,8-substituted and chlorophenols-route PCDD/F-congeners are especially documented.

Iron chloride is often cited as catalyst of PCDD/F-formation, together with copper chloride. Conversely, iron chloride catalysis has been less studied during de novo tests. This paper presents such de novo test data, derived from model fly ash incorporating iron (III) chloride and established over a vast range of temperature and oxygen concentration in the gas phase. Both PCDD/F-output and its signature are extensively characterised, including homologue and congener profiles. For the first time, a complete isomer-specific analysis is systematically established, for all samples. Special attention is paid to the chlorophenols route PCDD/F, to the 2,3,7,8-substituted congeners, and to their relationship and antagonism.