TY - JOUR
T1 - Mitigation of bromine-containing products during pyrolysis of polycarbonate-based tetrabromobisphenol A in the presence of copper(I) oxide
AU - Oleszek, Sylwia
AU - Kumagai, Shogo
AU - Grabda, Mariusz
AU - Shiota, Kenji
AU - Yoshioka, Toshiaki
AU - Takaoka, Masaki
N1 - Funding Information:
This study was supported by a research grant from the Yonemori Seishin Ikuseikai Foundation , Kagoshima, Japan. We would like to express our gratitude to the Advanced Environmental System of the Department of Environmental Engineering at Kyoto University for providing the SEM-EDS equipment. We would also like to express our thanks to Prof. Itoh, Dr. Echigo, and Dr. Nakanishi of Kyoto University for providing the FT-IR equipment and to Prof. Shibata of Tohoku University for providing the IC and ICP-AES equipment.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/5/5
Y1 - 2021/5/5
N2 - Polycarbonate (PC) is an engineering thermoplastic that is widely used in electrical and electronic equipment. This plastic often contains tetrabromobisphenol A (TBBA), the most common brominated flame retardant. Thermal degradation of the PC-TBBA leads to generation of numerous bromo-organic products in the pyrolytic oil, hindering its appropriate utilization, as well as corrosive hydrogen bromide gas. The purpose of this study was to experimentally investigate and compare the pyrolysis products of PC-TBBA and PC-TBBA + Cu2O at various temperatures, with an emphasis on the yield and distribution of brominated compounds. In pyrolysis of PC-TBBA + Cu2O, at the maximum degradation temperature (600 °C), as much as 86% of total Br was trapped in the residue, while 3% and 11% were distributed in the condensate and gas fractions, respectively. In contrast, the distribution of Br from non-catalytic pyrolysis of PC-TBBA (600 °C) was 0.5% residue, 40% condensate, and 60% gas. The results of this study revealed that in the presence of Cu2O, organo-bromine products were most likely involved in Ullman-type coupling reactions, leading to early cross-linking of the polymer network that efficiently hinders their vaporization. HBr in the gas fraction was suppressed due to effective fixation of bromine in residue in the form of CuBr.
AB - Polycarbonate (PC) is an engineering thermoplastic that is widely used in electrical and electronic equipment. This plastic often contains tetrabromobisphenol A (TBBA), the most common brominated flame retardant. Thermal degradation of the PC-TBBA leads to generation of numerous bromo-organic products in the pyrolytic oil, hindering its appropriate utilization, as well as corrosive hydrogen bromide gas. The purpose of this study was to experimentally investigate and compare the pyrolysis products of PC-TBBA and PC-TBBA + Cu2O at various temperatures, with an emphasis on the yield and distribution of brominated compounds. In pyrolysis of PC-TBBA + Cu2O, at the maximum degradation temperature (600 °C), as much as 86% of total Br was trapped in the residue, while 3% and 11% were distributed in the condensate and gas fractions, respectively. In contrast, the distribution of Br from non-catalytic pyrolysis of PC-TBBA (600 °C) was 0.5% residue, 40% condensate, and 60% gas. The results of this study revealed that in the presence of Cu2O, organo-bromine products were most likely involved in Ullman-type coupling reactions, leading to early cross-linking of the polymer network that efficiently hinders their vaporization. HBr in the gas fraction was suppressed due to effective fixation of bromine in residue in the form of CuBr.
KW - Bromine distribution
KW - Catalytic effect
KW - Cross-coupling reactions
KW - Fixed bed reactor
KW - Pyrolysis
UR - http://www.scopus.com/inward/record.url?scp=85098701389&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85098701389&partnerID=8YFLogxK
U2 - 10.1016/j.jhazmat.2020.124972
DO - 10.1016/j.jhazmat.2020.124972
M3 - Article
C2 - 33388450
AN - SCOPUS:85098701389
VL - 409
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
SN - 0304-3894
M1 - 124972
ER -