Dioxion-/Furan-’Verbrennungsprofile’ aus Hochtemperaturprozessen

Present knowledge assumes that different mechanisms acting downstream in high temperature processes lead to the formation of polychlorinated dibenzo(p)dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Concerning the 17 2,3,7,8-Cl-substituted PCDD/F congeners in particular, there is new evidence for a single-step reaction type (recently reported in this publication series, of. also parts 1 and 2). A formation based on a combination of the several mechanisms, which have been proposed and discussed since 1985, becomes more and more unlikely. Qualitatively the PCDD/F formation downstream from high temperature processes depends rather on a thermodynamically forced single reaction step, and on pure statistical distribution quantitatively. This may be a new ‘Thermostat Synthesis’ instead of ‘de novo’.