De novo synthesis of polychlorinated dibenzo-p-dioxins and dibenzofurans Proposal of a mechanistic scheme

摘要: Abstract This paper presents a chemical reaction scheme for de novo synthesis of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) from carbon in fly ash. The consists the following mechanistic steps: (1) gaseous O2 chemisorbs upon metallic sites: + 2Cu → 2CuO; (2) oxygen is transferred to free site structure oxidized product: Cf CuO CO Cu; (3) course gasification, decomposition also produces some small aromatic compounds: C (graphitic layer) aO2 bCO2 cCO dAr. These compounds include PCBz, PCPh PCB which then undergo Ullmann coupling reactions leading PCDD F formation. Alternatively, could be formed directly as consequence in-plane complexes: dAr e ; (4) halogenation/dehalogenation on structure, DD may occur concurrently above transformations; (5) Fs . Major experimental observations can rationalized using scheme. Experimental techniques further investigations are discussed.