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International Journal of Environment Science and Technology
Center for Environment and Energy Research and Studies (CEERS)
ISSN: 1735-1472 EISSN: 1735-1472
Vol. 11, No. 5, 2014, pp. 1459-1472
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Bioline Code: st14142
Full paper language: English
Document type: Research Article
Document available free of charge
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International Journal of Environment Science and Technology, Vol. 11, No. 5, 2014, pp. 1459-1472
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Partial pyrolysis of olive wood to improve its sorption of chlorophenols and nitrophenols
El-Sheikh, A.H.
Abstract
Partial pyrolysis alters the chemical and textural
properties of the lignocellulosic material. This work reports
the effect of partial pyrolysis of olive wood on adsorption
isotherms, kinetics and thermodynamics of chloro and
nitrophenols. Shape of adsorption isotherms of the partially
pyrolyzed sorbents was L3 for phenol; L2 for 2-nitrophenol
and 2,4-dinitrophenol; H3 for 2-chlorophenol, 3-chlorophenol
and 4-nitrophenol; and H2 for 4-chlorophenol. The
pyrolyzed olive wood sorbents obeyed Langmuir and Freundlich
models. Pyrolysis raised adsorption capacity,
favorability and spontaneity; the adsorption became more
exothermic; the randomness decreased. The adsorption was
mainly physical; it occurred first by film diffusion then by
pore-filling. Adsorption followed second-order rate kinetics.
Adsorption of phenols on olive wood seemed to be
governed by hydrophobic interaction. Washing the pyrolyzed
olive wood with ethanol caused a decrease in
adsorption capacity, favorability and spontaneity, and the
adsorption became less exothermic. This indicated that
pyrolysis produced species on the olive wood surface that
played a significant role in phenols adsorption.
Keywords
Adsorption models; Olive wood; Phenols; Pyrolysis
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