Mechanism of formation of PCDD/PCDF in industrial waste incineration and a method of prevention of their formation

Abstract There are very few studies on the mechanism of formation of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and related compounds in industrial waste incinerators (IWIs) and possible techniques to prevent their formation. It has been shown in our laboratories that fly ash from municipal solid waste incinerators (MSWIs) catalyzes the reactions leading to the formation of PCDD/PCDF at about 300 to 400°C. In the current investigation laboratory experiments were conducted to study the catalytic activity of the samples from an IWI towards the formation of PCDDs and PCDFs from precursors. Results show that IWI samples are catalytically active towards the formation of PCDDs. Several inhibitors and their mixtures such as inorganic and organic bases were tested to study their effect on the catalytic activity of the IWI samples and MSWI fly ash samples towards the prevention of formation of PCDD/PCDF from precursors.