Adsorption has been investigated to remove phenol from an aqueous solution (concentration
range from 0.1 to 1.6 g·L-1). Zeolites were used as adsorbents, and adsorption properties were
compared to those of an activated carbon. To adsorb phenol selectively from water, adsorbents
must be hydrophobic, i.e., zeolites owning a high Si/Al ratio. Thus, purely siliceous BEA zeolite
(Si/Al = ∞) was used with success; the adsorption capacity was slightly higher at low phenol
concentration (≤1.6 g·L-1) than the one of activated carbon (surface area close to 1150 m2·g-1).
Furthermore, siliceous BEA zeolite appears as an efficient adsorbent able to be easily regenerated
while keeping these initial properties.
The characterization of industrial coked resid fluid catalytic cracking (RFCC) catalysts is
reported. The aim is to provide insight into the coke deposition on commercial resid fluid catalytic
cracking catalysts sampled after the stripper of a commercial RFCC unit and to relate it to the
potential process chemistry. Physicochemical techniques were used to characterize the used
catalysts and the deposited coke. 95% of the coke was insoluble in CH2Cl2. This coke was located
in the mesopores of the catalyst matrix. The results suggest the existence of domains of
polyaromatic and heterogeneously distributed coke, in which saturated hydrocarbons are trapped.
IR spectroscopy of adsorbed pyridine shows that the largest fraction of strong Brønsted acid
sites is free after the catalyst has passed the stripper. The results indicate that for RFCC not
the local deactivation of the acid sites but rather blocking of domains of the catalyst is the most
important mode of deactivation after passing through the riser reactor.
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