TY - JOUR
T1 - Resource recovery via catalytic fast pyrolysis of polystyrene using zeolites
AU - Ojha, Deepak Kumar
AU - Vinu, R.
N1 - Publisher Copyright:
© 2015 Elsevier B.V.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Abstract This study focuses on selective production of valuable chemicals from polystyrene (PS) via catalytic fast pyrolysis using micropyrolyzer-GC/MS set-up. Catalytic fast pyrolysis of PS was performed using eight different zeolites belonging to ZSM-5, zeolite-β, and zeolite-Y families. The catalysts were characterized for the strength of Brønsted acid sites and pore size distribution. The composition of PS:catalyst was optimized at 1:2.3 ± 0.2 wt./wt. to enhance the yield of benzene, at the same time reduce the yield of condensed ring fragments like indene and indane derivatives. The yields of various products correlated well with specific properties of zeolites like relative strength of Brønsted acid sites, specific surface area, and pore volume. Importantly, the yield of benzene increased, while that of styrene, α-methyl styrene, and dimers decreased with Brønsted acidity. Zeolite-β hydrogen and zeolite-Y ammonia catalysts resulted in the formation of up to 50 wt.% of benzene. High temperatures led to a reduction in benzene yield and promoted the formation of styrene, α-methyl styrene, and ethyl benzene. The observed product distribution with different zeolites and at different temperatures was corroborated using the relative importance of the primary protonation pathways involved in catalytic fast pyrolysis of PS.
AB - Abstract This study focuses on selective production of valuable chemicals from polystyrene (PS) via catalytic fast pyrolysis using micropyrolyzer-GC/MS set-up. Catalytic fast pyrolysis of PS was performed using eight different zeolites belonging to ZSM-5, zeolite-β, and zeolite-Y families. The catalysts were characterized for the strength of Brønsted acid sites and pore size distribution. The composition of PS:catalyst was optimized at 1:2.3 ± 0.2 wt./wt. to enhance the yield of benzene, at the same time reduce the yield of condensed ring fragments like indene and indane derivatives. The yields of various products correlated well with specific properties of zeolites like relative strength of Brønsted acid sites, specific surface area, and pore volume. Importantly, the yield of benzene increased, while that of styrene, α-methyl styrene, and dimers decreased with Brønsted acidity. Zeolite-β hydrogen and zeolite-Y ammonia catalysts resulted in the formation of up to 50 wt.% of benzene. High temperatures led to a reduction in benzene yield and promoted the formation of styrene, α-methyl styrene, and ethyl benzene. The observed product distribution with different zeolites and at different temperatures was corroborated using the relative importance of the primary protonation pathways involved in catalytic fast pyrolysis of PS.
KW - Benzene
KW - Brønsted acidity
KW - Catalytic fast pyrolysis
KW - Polystyrene
KW - Styrene
KW - ZSM-5
KW - Zeolite-Y
KW - Zeolite-β
UR - http://www.scopus.com/inward/record.url?scp=84930764376&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84930764376&partnerID=8YFLogxK
U2 - 10.1016/j.jaap.2015.02.024
DO - 10.1016/j.jaap.2015.02.024
M3 - Article
AN - SCOPUS:84930764376
SN - 0165-2370
VL - 113
SP - 349
EP - 359
JO - Journal of Analytical and Applied Pyrolysis
JF - Journal of Analytical and Applied Pyrolysis
M1 - 3433
ER -