Viktor Ladnak et al.
FULL PAPERS
ganic products. Afterwards the ionic liquid was re-injected
into the flask and the experiment was repeated as described
before.
from the loop reactor the remaining alumina and hence the
remaining acidity of the ionic liquid in the reactor could be
easily calculated.
Continuous Experiments[15]
The acidic ionic liquid, typically about 45 g of References
AlCl3/[BMIM][(CF3SO2)2N]=2.5, was injected in the loop
A
ACHTREUNG
reactor that was completely evacuated for several hours and
filled with inert gas (N2). The aromatic compound (diluted
with cyclohexane) was introduced first in the liquid phase
by HPLC pump (toluene/cyclohexane: 0.4–40 mLminÀ1) so
that the reactor was totally filled with liquid. The reaction
started with the liquid introduction of propene by HPLC
pump (propene: 0.01–10 mLminÀ1). A back-pressure regula-
tor ensured a constant pressure (0–60 bar). The total volume
of the continuous rig was determined to be 285 mL, showing
11% of short circuit flow and 31% of the flow not fully
back-mixed (e.g. due to dead volume in the separator). Two
static mixers (Sulzer SMX DN6) dispersed the ionic liquid
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with the organic reactants.
A circulation pump (1–
4.5 LminÀ1) provided enough energy for a fine dispersion,
while heat exchangers controlled the reaction temperature
(15–958C). At the gravimetric phase separator, a diffuser
absorbed out the kinetic energy of the dispersed liquids so
that the ionic liquid settled down and were recirculated in
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circulated several times before leaving the reactor.
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was neutralised by washing with distilled water and analysed
by gas chromatography.
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charged from the reactor, the water from the neutralising
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Adv. Synth. Catal. 2007, 349, 719 – 726