Abstract (EN):
Powder, agglomerates, and tablets of the microporous
zirconium(IV) terephthalate metal¿organic framework
UiO-66 were evaluated for the selective adsorption and
separation of xylene isomers in the liquid phase using n-heptane
as the eluent. Pulse experiments, performed at 313 K in the
presence of n-heptane, revealed the o-xylene preference of this
material, which was further confirmed by binary and multicomponent
breakthrough experiments in the presence of m- and
p-xylene, resulting in selectivities at 313 K of 1.8 and 2.4 with
regards to m-xylene and p-xylene, respectively. Additionally,
because p-xylene is the less retained isomer, UiO-66 presents a
selectivity pattern that is reverse of that of the xylenes' molecular
dimension with respect to shape selectivity. The shaping of the material as tablets did not significantly change its selectivity toward the
o-xylene isomer or toward p-xylene, which was the less retained isomer, despite a loss in capacity. Finally, the selectivity behavior of
UiO-66 in the liquid n-heptane phase makes it a suitable material for o-xylene separation in the extract (heavy product) or p-xylene
separation in the raffinate (light product) by simulated moving bed technology.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
9