TY - JOUR
T1 - Enhanced debromination by Fe particles during the catalytic pyrolysis of non-metallic fractions of printed circuit boards over ZSM-5 and Ni/SiO2-Al2O3 catalyst
AU - Ma, Chuan
AU - Kamo, Tohru
N1 - Funding Information:
This research was supported by Japan Oil, Gas and Metals National Corporation (JOGMEC).
Publisher Copyright:
© 2018 Elsevier B.V.
PY - 2019/3
Y1 - 2019/3
N2 - A two-stage fixed-bed reactor was used to investigate the catalytic pyrolysis of non-metallic fractions of printed circuit boards (PCBs) over ZSM-5 and Ni/SiO2-Al2O3 (Ni/SA) catalysts. The addition of Fe particles to the catalyst was evaluated for bromine removal from the pyrolysis products. Results showed that the oil yield was significantly reduced from 50.1 wt% to 41.2 wt% by ZSM-5 catalyst and 36.0 wt% by Ni/SA catalyst, respectively, with corresponding increases of aqueous and gas products. The addition of Fe particles to ZSM-5 catalyst slightly altered the product yields, whereas the mixture of Fe and Ni/SA catalyst largely reduced the oil yield to 25.6 wt%, along with the highest gas yield of 20.3 wt%. The results suggested that the mixture of Fe-Ni/SA catalyst accelerated the cracking of vapor products derived from PCBs rather than the Fe-ZSM-5 mixture. Moreover, ZSM-5 catalyst favored the formation of single ring aromatics in the oils, such as benzene and toluene. The presence of Fe particles increased the concentration of phenol in the oils. The ZSM-5 and Ni/SA catalyst demonstrated great debromination performance for the conversion of organobromine compounds into HBr, reducing the bromine content in oils from 8.74 wt% to 5.96 wt% and 5.46 wt%, respectively. Furthermore, the addition of Fe particles reduced both the organobromine compounds and evolved HBr, which resulted in less than 3.8% of Br being transferred in the oil whereas more than 50% of bromine was fixed in Fe particles.
AB - A two-stage fixed-bed reactor was used to investigate the catalytic pyrolysis of non-metallic fractions of printed circuit boards (PCBs) over ZSM-5 and Ni/SiO2-Al2O3 (Ni/SA) catalysts. The addition of Fe particles to the catalyst was evaluated for bromine removal from the pyrolysis products. Results showed that the oil yield was significantly reduced from 50.1 wt% to 41.2 wt% by ZSM-5 catalyst and 36.0 wt% by Ni/SA catalyst, respectively, with corresponding increases of aqueous and gas products. The addition of Fe particles to ZSM-5 catalyst slightly altered the product yields, whereas the mixture of Fe and Ni/SA catalyst largely reduced the oil yield to 25.6 wt%, along with the highest gas yield of 20.3 wt%. The results suggested that the mixture of Fe-Ni/SA catalyst accelerated the cracking of vapor products derived from PCBs rather than the Fe-ZSM-5 mixture. Moreover, ZSM-5 catalyst favored the formation of single ring aromatics in the oils, such as benzene and toluene. The presence of Fe particles increased the concentration of phenol in the oils. The ZSM-5 and Ni/SA catalyst demonstrated great debromination performance for the conversion of organobromine compounds into HBr, reducing the bromine content in oils from 8.74 wt% to 5.96 wt% and 5.46 wt%, respectively. Furthermore, the addition of Fe particles reduced both the organobromine compounds and evolved HBr, which resulted in less than 3.8% of Br being transferred in the oil whereas more than 50% of bromine was fixed in Fe particles.
KW - Bromine fixation
KW - Catalytic pyrolysis
KW - Fe particles
KW - Printed circuit boards
KW - Solid acids
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U2 - 10.1016/j.jaap.2018.12.021
DO - 10.1016/j.jaap.2018.12.021
M3 - Article
AN - SCOPUS:85058810527
VL - 138
SP - 170
EP - 177
JO - Journal of Analytical and Applied Pyrolysis
JF - Journal of Analytical and Applied Pyrolysis
SN - 0165-2370
ER -