Characterizing the emission of chlorinated/brominated dibenzo-p-dioxins and furans from low-temperature thermal processing of waste printed circuit board

This study focuses primarily on the inventory of PCDD/Fs and PBDD/Fs associated with the low-temperature thermal processing of scrap printed circuit boards (PCBs). Twelve 2,3,7,8-substituted PBDD/Fs congeners were found in various sample outputs, with a total content of 60,000 ng TEQ/kg at 250 °C under air atmosphere. A rapid increase of PBDD/Fs was produced with 160,000 ng TEQ/kg, at 275 °C—about twice that under the N2 atmosphere. At 275 °C, the total contents of PCDD/Fs were only 170 and 770 ng TEQ/kg under an N2 and air atmospheres respectively. The results reveal that a large contribution of PBDD/Fs emission may be expected from the dismantling or any other thermal processing of PCB scrap. PCDD/Fs, however, are formed and released into the environment in a variety of ways. Additional research is required to look for the causal factors that affect emissions.

► This study characterizing the emissions of PBDD/Fs and PCDD/Fs from scrap PCBs.
► Both PBDD/Fs and PCDD/Fs have been found to form in all experimental samples.
► The profile of PBDD/Fs was similar to those from environmental samples.
► The concentration of PCDD/Fs is quite lower than PBDD/Fs.
► PCDD/Fs are formed and released into the environment in a variety of ways.