K.M. Parida et al. / Journal of Molecular Catalysis A: Chemical 318 (2010) 85–93
93
3
.2.5. Effect of catalyst amount
The effects of catalyst amount on amination of benzene were
ples prepared by co-condensation method shows higher amount
of copper in framework compared to samples prepared by impreg-
nation technique. Cu-amine-MCM-41 samples show good activity
for single step liquid phase amination of benzene to aniline. The
Cu-amine-MCM-41 (20) modified sample shows highest catalytic
activity having 72.2% benzene conversion and 100% aniline selec-
tivity. Samples prepared by co-condensation method shows better
activity than samples prepared by impregnation technique.
studied and the results are shown in Fig. 12. With the increase in
catalyst amount from 0.01 g to 0.05 g, the benzene conversion, ani-
line and hydroxylamine selectivity increased from 23.5% to 72.7%,
9
0% to 100% and 43.3% to 95%, respectively. As the amount of cata-
lyst further increases from 0.05 g to 0.1 g, the benzene conversion
also increased from 72.2% to 83% but aniline and hydroxylamine
selectivity decreased to 70% and 67.5% respectively. This may
be due to the formation of more side products and unselective
decomposition of hydroxylamine resulting decrease in formation
References
•
+
[1] D. Zhao, J. Feng, Q. Huo, N. Melosh, G.H. Frederickson, B.F. Chmelka, G.D. Stucky,
Science 279 (1999) 548–552.
of protonated amino ( NH3 ) radical.
[
2] S.A. Bagshaw, E. Prouzet, T.J. Pinavia, Science 269 (1995) 1242–1244.
3.3. Recyclability of the catalyst
[3] R. Ryoo, J.M. Kim, C.H. Ko, C.H. Shin, J. Phy. Chem. 100 (1996) 17718–17721.
[
[
4] S. Inagaki, A. Koiwai, N. Suzuki, Y. Fukushima, K. Kuroda, Bull. Chem. Soc. Jpn.
9 (1996) 1449–1457.
5] L. Mercier, T.J. Pinnavaia, Chem. Mater. 12 (2000) 188–196.
6
Cu-amine-MCM-41 (20) is used for recycling study. In order to
regenerate the catalyst after 2 h reaction, the catalyst was separated
by filtration, washed with double distilled water several times,
[6] Y. Mori, T.J. Pinnavaia, Chem. Mater. 13 (2001) 2173–2178.
[7] A. Taguchi, F. Schuth, Micropor. Mesopor. Mater. 77 (2004) 1–45.
[8] W.H. Zhang, X.-B. Lu, J.-H. Xiu, Z.-L. Hua, L.-X. Zhang, M. Robertson, J.-L. Shi,
D.-S. Yan, J.D. Holmer, Adv. Funct. Mater. 14 (2004) 544–552.
◦
dried at 110 C and used in the amination reaction with a fresh
reaction mixture. In the regenerated sample after four cycles, the
yield decreases by 3.22%.
[
9] A. Bhaumik, T. Tatsumi, J. Catal. 189 (2000) 31–39.
[10] N. Igarashi, S. Kidani, R. Ahemaito, K. Hashimoto, T. Tatsumi, Micropor. Meso-
por. Mater. 81 (2005) 97–105.
[
[
[
[
11] K. Hara, JP 6-293715 (21 October 1994).
4
. Conclusion
12] J. Becker, W.F. Holderich, Catal. Lett. 54 (1998) 125–128.
13] H.E. Stitt, S.D. Jackson, PCT WO 0 009 473 (2000).
14] D. Poojary, R. Borade, A. Hagemeyer, C. Dube, Z.P. Zhou, U. Nothelis, R. Armbrust,
C. Rasp, PCT WO 0 069 804 (2000).
Copper modified amine functionalized MCM-41 was prepared
by co-condensation and impregnation method. The XRD pattern
shows mesoporous nature of the material remains intact after
amine and copper modification. Surface area, pore diameter and
pore volume decrease with an increase in Cu content. FT-IR and
DRS studies confirmed the presence of Cu and amino groups in
the framework and frame wall position respectively. NMR shows
the presence of T2 and T3 functionalities confirmed the existence
of the covalent linkage between the organic groups and the sil-
ica surface. Amine functionalized and Cu-amine modified MCM-41
show greater degree of condensation and higher hydrothermal
stability than that of parent sample. The 20Cu-amine modified
sample shows 39% of surface coverage of parent MCM-41. Sam-
[
15] K.M. Parida, S.S. Dash, S. Singha, Appl. Catal. A: Gen. 351 (2008) 59–67.
[16] L.F. Zhu, B. Guo, D.Y. Tang, X.K. Hu, G.Y. Li, C.W. Hu, J. Catal. 245 (2007) 446–455.
[
17] M.A. Mantegazza, G. Leofanti, G. Petrini, M. Padovan, A. Zeccina, S. Bordiga,
in: V.C. Corberan, S.V. Bellon (Eds.), New Developments in Selective Oxidation,
Elsevier, New York, 1994, p. 51.
[18] M. Selvaraj, P.K. Sinha, K. Lee, I. Ahn, A. Pandurangan, T.G. Le, Micropor. Meso-
por. Mater. 78 (2005) 139–149.
[
19] T. Chen, Z.J. Fu, L.F. Zhu, C.W. Hu, A.M. Tian, Acta Chim. Sinica (Huanxue Xuebao)
1 (2003) 170.
[20] H. Praliand, S. Mikhailenko, Z. Chajar, M. Primet, Appl. Catal. B: Environ. 16
1998) 359–365.
6
(
[
21] A. Citterio, A. Gentile, F. Minisci, V. Navaovini, M. Sevravalle, S. Ventura, J. Org.
Chem. 49 (1984) 4479–4482.
[22] N.I. Kuznetsova, L.I. Kuznetsova, L.G. Dutesheva, V.A. Likholobov, G.P. Pez, H.
Cheng, J. Mol. Catal. A 161 (2000) 1–9.