Paper
RSC Advances
ꢀ
The temperature was then raised to 600 C at a rate of
1
Table 2 Compositions of the hierarchical ZSM-5 zeolite aggregates
ꢀ
0 C min and the TPD proles for chemisorbed NH were
3
ꢂ1
Composition in molar ratios
monitored by a TCD detector. Inductively coupled plasma
atomic emission spectrometry (ICP-AES) was obtained on
a Thermo IRIS Intrepid II XSP atomic emission spectrometer
a
Samples
SiO
2
Al
2
O
3
Na
2
O
H
2
O
Seed
HZ5-A
HZ5-B
HZ5-C
HZ5-D
HZ5-E
HZ5-F
1
1
1
1
1
1
0.033
0.033
0.067
0.010
0.033
0.033
0.1
0.1
0.1
0.1
0.1
0.1
24
24
24
24
13
50
0.015
0.05
0.015
0.015
0.015
27
29
aer dissolving the samples in HF solution. Al and Si solid-
state MAS NMR spectra were recorded on a Bruker DSX300
spectrometer.
The alkylation of phenol with tert-butanol was carried out at
ꢀ
0.015 125 C for 4 h under stirring in a 50 ml round-bottomed ask
immersed in a thermostatic oil bath and equipped with
a condenser. The stirring was sufficiently strong to rule out the
external diffusion on catalytic performance for all of the
batches. In a typical batch, 0.15 g of catalyst, 7.78 g of cyclo-
a
2
Based on the total SiO .
and the required seed gel. The molar composition of the
synthetic mixtures was 1SiO : 1/x Al : 0.1Na O : yH O : seed
gel, (equal to z wt% of SiO
; x ¼ 30, 60, 100; y ¼ 13, 24, 50; z ¼
.5, 5, respectively). Aer being stirred for 2 h, the mixtures were
hexane as solvent, 0.74 g of tert-butanol and 0.47 g of phenol
were used. The product was analyzed using a Shimadzu GC-
2
2
O
3
2
2
2
2014 gas chromatograph equipped with a 30 m Wax capillary
1
column and a ame ionization detector.
transferred into a Teon-lined stainless steel autoclave, where
ꢀ
they were heated at 175 C statically under autogenous pressure
for the prescribed time (0–168 h). The obtained products were
Conflicts of interest
ꢀ
ltered, washed and then dried overnight at 100 C. To get the
H-form ZSM-5 zeolites, the as-synthesized samples were directly There are no conicts to declare.
ꢀ
ion-exchanged using 0.6 M NH
4
NO
3
solution at 80 C for 2 h
ꢀ
without calcination and then calcined at 550 C in air for 6 h.
The obtained samples were denoted as HZ5-X (X ¼ A, B, C, D, E,
F) based on the molar compositions as shown in Table 1. Here,
without a subsequent calcination, all the as-synthesized
samples had been directly ammonium ion exchange and the
Acknowledgements
We gratefully acknowledge the nancial support by NSFC
(21503081 and 21573073), China Ministry of Science and
Technology (2016YFA0202800) and Shanghai Leading Academic
Discipline Project (No. B409).
H-form ZSM-5 zeolites were obtained by ion exchange (4 times)
ꢀ
with 0.6 M NH
4
NO
3
solution at 80 C for 1 h, follow by calci-
ꢀ
nation at 550 C in air for 6 h (Table 2).
References
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ꢀ
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ꢀ
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ꢀ
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ꢀ
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(
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p/p
¼ 0.99, and the micropore volume was calculated from the
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0
0
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ꢀ
1
00 mg of the H-type samples were pretreated at 600 C for 2 h 12 T. M ¨a urer, S. P. M u¨ ller and B. Kraushaar-Czarnetzki, Ind.
ꢀ
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3
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RSC Adv., 2018, 8, 2751–2758 | 2757