Mendeleev Commun., 2013, 23, 168–170
3 T. Zaki, J. Colloid Interface Sci., 2005, 284, 606.
100
80
60
40
20
0
4 M. M. Doheim, S. A. Hanafy and G. A. El-Shobaky, Mater. Lett., 2002,
55, 304.
5 Y. Xiao, X. Li, Z. Yuan, J. Li and Y. Chen, Catal. Lett., 2009, 130, 308.
6 X. Zhang, R. Wang, X. Yang and F. Zhang, Microporous Mesoporous
Mater., 2008, 116, 210.
7 K. Ramesh, L. M. Hui,Y.-F. Han andA. Borgna, Catal. Commun., 2009,
10, 567.
8 N. Zhan, Y. Hu, H. Li, D. Yu, Y. Han and H. Huang, Catal. Commun.,
2010, 11, 633.
9 J. Haber, K. Pamin, L. Matachowski, B. Napruszewska and J. Poltowicz,
J. Catal., 2002, 207, 296.
200
250
300
350
10 D. Varisli, T. Dogu and G. Dogu, Chem. Eng. Sci., 2007, 62, 5349.
11 P. Vazquenz, L. Finkielsztein, B. Lantano, G. Moltrasio and J. Aguirre,
J. Mol. Catal. A: Chem., 2000, 161, 223.
T/°C
Figure 5 Effect of reaction temperature on the selectivity for diethyl ether
( , ) and ethylene ( , ) of the ( , ) 30CeHPW/MCM and ( , ) 30CuHPW/
MCM catalysts.
12 L. Degirmenci, N. Oktar and G. Dogu, Ind. Eng. Chem. Res., 2009, 48,
2566.
13 W. Trakarnpruk, Mendeleev Commun., 2013, 23, 46.
14 V. V. Bokade and G. D. Yadav, Appl. Clay Sci., 2011, 53, 263.
15 G. C. Bond, S. J. Frodsham, P. Jubb, E. F. Kozhevnikova and I. V.
Kozhevnikov, J. Catal., 2012, 293, 158.
16 D. Varisli, T. Dogu and G. Dogu, Ind. Eng. Chem. Res., 2008, 47, 4071.
17 G. Karthikeyana and A. Pandurangan, J. Mol. Catal. A: Chem., 2009,
311, 36.
temperature to reach 91.5 and 86.6% for 30CeHPW/MCM and
30CuHPW/MCM, respectively, at 350°C. Even though the syn-
thesized catalysts were calcined at 300°C but the reaction was
performed at 350°C, the catalysts were stable. The HPW salts
on silica were reported to be stable at <400°C.22
18 B. Li, W. Maa, C. Han, J. Liu, X. Pang and X. Gao, Microporous
Dehydration of ethanol can occur by two competitive paths.
The first one is the intramolecular dehydration of ethanol to
ethylene, whereas the second is the intermolecular dehydration
of ethanol to diethyl ether.25 At 200°C, diethyl ether is the main
product. This may be attributed to the requirement of intermole-
cular dehydration of ethanol (needs 2 mol) to form diethyl ether
at a lower energy than the intramolecular dehydration of ethanol
to form ethylene. With an increase in the temperature to 350°C,
the conversion of ethanol grew but the selectivity for diethyl ether
decreased and the selectivity for ethylene increased due to the
decomposition of diethyl ether. The 30CeHPW/MCM catalyst gave
higher selectivity for diethyl ether. The Cu0.5H2.5PMo12O40 was
reported to show low conversion (65.8%) and selectivity for
diethyl ether (67.1%) at 200°C but a much higher activity at
250°C (90.5% conversion with 81.1% selectivity).21
Mesoporous Mater., 2012, 156, 73.
19 A. Ciftci, D. Varisli, K. C. Tokay, N. A. Sezgi and T. Dogu, Chem. Eng. J.,
2012, 207–208, 85.
20 J. Gurgul, M. Zimowska, D. Mucha, R. P . Socha and L. Matachowski,
J. Mol. Catal. A: Chem., 2011, 351, 1.
21 T. T. Ali, S. A. Al-Thabaiti, A. O. Alyoubi and M. Mokhtar, J. Alloys
Compd., 2010, 496, 553.
22 Z. Zhu and W. Yang, J. Phys. Chem. C, 2009, 113, 17025.
23 R. Fazaeli and H. Aliyan, Appl. Catal. A: Gen., 2009, 353, 74.
24 A. M. Alsalme, P. V. Wiper, Y. Z. Khimyak, E. F. Kozhevnikova and
I. V. Kozhevnikov, J. Catal., 2010, 276, 181.
25 A. Gayubo, A. Tarrio, A. Aguayo, M. Olazar and J. Bilbao, Ind. Eng.
Chem. Res., 2001, 40, 3467.
References
1 D. Varislia, T. Dogua and G. Dogu, Chem. Eng. Sci., 2010, 65, 153.
2 T. Kito-Borsa, D. A. Pacas, S. Selim and S. W. Cowley, Ind. Eng. Chem.
Res., 1998, 37, 3366.
Received: 21st January 2013; Com. 13/4049
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