Removal of Halogens from Pyrolysis Oils Produced by Plastics Containing Flame Retardants

Abstract

Plastics containing brominated flame retardants are commonly used in electrical and electronic products, and disposal or recycle of these products is difficult because of their halogen content. In this study, brominated acrylonitrile butadiene styrene (Br-ABS) was pyrolyzed at 450 °C. The halogen content in the product oil was reduced by addition of sodium hydroxide (NaOH) and pine charcoal. The mass fraction of bromine in the oil obtained without the NaOH or charcoal was 3.2 %, whereas those in the oils obtained with NaOH and charcoal were 1.74 % and 1.25 %, respectively. Using both NaOH and charcoal, the bromine mass fraction in the oil was reduced to 0.6 %. Combustion tests were used to determine the colorific values of pyrolysis oils with various bromine contents, and any corrosion that could limit their use as an alternative fuel was evaluated after these tests. Pyrolysis oil with a bromine content of less than 2000 mg/L could be used as fuel without corrosion.