1
06
C. Antonetti et al. / Applied Catalysis A: General 421–422 (2012) 99–107
Table 4
Catalytic activity of the supported ruthenium catalysts in the hydrogenation of p-CNB to p-CAN for Samples 8, 9 and for 0.5% wt Ru/Al2O3 Aldrich (reaction conditions: 60 C;
MPa of hydrogen; 0.5 mg of Ru; 0.4 g of p-chloronitrobenzene; and 50 ml of CH3OH as solvent).
◦
4
Sample
Sample description
A30 min
(
A100%
(mol/g Ru h)
Sel. at 100%
conversion (%)
mol/g Ru h)a
b
p-CAN
AN
Comm. Ru/Al2O3
Sample 8
Sample 9
0.5 wt% Ru/Al2O3 Aldrich
0.15 wt% Ru/␥-Al2O3, no PVP, (H2O/EtOH)
1.2 wt% Ru/␥-Al2O3, no PVP, (H2O/EtOH)
0.50
4.87
1.32
0.73
1.69
0.73
95.5
100
97.5
4.5
0
2.5
a
Activity measured at 30 min of reaction.
Activity measured at 100% conversion.
b
Table 5
◦
Catalytic activity of the supported ruthenium catalysts in the hydrogenation of p-CNB to p-CAN for Samples 2 and 9 (reaction conditions: 60 C; 4 MPa of hydrogen; 0.5 mg
of Ru; 0.4 g of p-chloronitrobenzene; and 50 ml of CH3OH as solvent).
Sample
Sample Description
A30 min
(
A100%
(mol/g Ru h)
Sel. at 100%
conversion (%)
mol/g Ru h)a
b
p-CAN
AN
i
Sample 2
Sample 9
1.3 wt% Ru/CNT (HNO3), no PVP, ( PrOH)
3.66
1.32
0.92
0.73
100
97.5
0
2.5
1.2 wt% Ru/␥-Al2O3, no PVP, (H2O/EtOH)
a
Activity measured at 30 min of reaction.
Activity measured at 100% conversion.
b
the reaction sites [33]. Besides, CNTs are electron conductors and
some charge transfers which can modify the electronic density at
ruthenium centres could occur [41]: it is well known that the gen-
eration of a positive charge on the ruthenium should increase the
catalytic activity for this reaction [10].
[13] G.Y. Fan, L. Zhang, H.Y. Fu, M.L. Yuan, R.X. Li, H. Chen, X.J. Li, Catal. Commun. 11
2010) 451–455.
(
[
[
14] J. Chen, N. Yao, R. Wang, J. Zhang, Chem. Eng. J. 148 (2009) 164–172.
15] D. He, H. Shi, Y. Wu, B.Q. Xu, Green Chem. 9 (2007) 849–851.
[16] M. Pietrowski, M. Zielinski, M. Wojciechowska, Catal. Lett. 128 (2009) 31–35.
[
17] V. Kratky, M. Kralik, M. Mecarova, M. Stolcova, L. Zalibera, M. Hronec, Appl.
Catal. A: Gen. 235 (2002) 225–231.
[
18] X. Han, R. Zhou, G. Lai, B. Yue, X. Zheng, J. Mol. Catal. A: Chem. 209 (2004) 83–87.
4
. Conclusions
[19] X. Han, R. Zhou, G. Lai, X. Zheng, Catal. Today 93–95 (2004) 433–437.
[
20] H.-W. Liu, H.-B. Pan, G.-X. Tian, H.-J. Chen, K.-H. Chiu, J.-F. Jen, J. Lo, C.M. Wai,
Synth. Commun. 41 (17) (2011) 2624–2630.
A novel approach for the synthesis of ruthenium nanoparticles
[
21] P. Baumeister, M.F. Studer, F. Roessler, in: G. Ertl, H. Knozinger, J. Weitkamp
(Eds.), Handbook of Heterogeneous Catalysis, VCH, Weinheim, 1997.
22] R.J. Maleski, E.T. Mullins, US 6,034,276.
supported on CNTs was adopted, working under MW irradiation
in the presence of a low boiling point alcohol or of a mixture alco-
hol (isopropanol/ethanol)/water. These ruthenium catalysts have
been employed for the selective hydrogenation of p-CNB to p-CAN
and result efficient catalysts for the selective reduction of the nitro
group in p-CNB, while the C Cl bond in the same p-CNB molecule
maintains intact. Under mild reaction conditions, the complete sub-
strate conversion with a total selectivity to the target product has
been reached.
[
[
23] J. Ning, J. Xu, J. Liu, H. Miao, H. Ma, C. Chen, X. Li, L. Zhou, W. Yu, Catal. Commun.
8
(2007) 1763–1766.
[24] B. Zuo, Y. Wang, Q. Wang, J. Zhang, N. Wu, L. Peng, L. Gui, X. Wang, R. Wang, D.
Yu, J. Catal. 222 (2004) 493–498.
[
[
25] M. Liu, W. Yu, H. Liu, J. Mol. Catal. A: Chem. 138 (1999) 295–303.
26] A. Tijani, B. Coq, F. Figueras, Appl. Catal. 76 (1991) 255–266.
[27] M. Liu, J. Zhang, J. Liu, W.W. Yu, J. Catal. 278 (2011) 1–7.
[
[
[
28] M. Pietrowski, Green Chem. 13 (2011) 1633–1635.
29] S. Zhao, H. Liang, Y. Zhou, Catal. Commun. 8 (2007) 1305–1309.
30] Y.W. Chen, N. Sasirekha, Ind. Eng. Chem. Res. 48 (2009) 6248–6255.
This study underlines the fast, reproducible and sustainable
preparation of these ruthenium catalysts employing not only mild
conditions, but also green solvents. This procedure has been trans-
lated to the preparation of ruthenium nanoparticles supported on
alumina, characterized by catalytic performances overcoming the
corresponding commercial system.
[31] X.L. Yang, H.F. Liu, H. Zhong, J. Mol. Catal. A: Chem. 147 (1999) 55–62.
[32] J. Zhang, Y. Wang, H. Ji, Y. Wei, N. Wu, B. Zuo, Q. Wang, J. Catal. 229 (2005)
1
14–118.
33] N. Mahata, A.F. Cunha, J.J.M. Orfao, J.L. Figueiredo, Catal. Commun. 10 (2009)
203–1206.
[34] C. Wang, J. Qiu, C. Liang, L. Xing, X. Yang, Catal. Commun. 9 (2008) 1749–1753.
[
1
[35] R. Zanella, C. Louis, S. Giorgio, R. Touroude, J. Catal. 223 (2004) 328–339.
[36] Y. Chen, J. Qui, X. Wang, J. Xiu, J. Catal. 242 (2006) 227–230.
[37] F. Cárdenas-Lizana, Z.M. de Pedro, S. Gomez-Quero, M.A. Keane, J. Mol. Catal.
A: Chem. 326 (2010) 48–54.
Acknowledgment
[
[
38] Y.Z. Chen, Y.C. Chen, Appl. Catal. A: Gen. 115 (1994) 45–57.
39] P. Serp, E. Castillejos, ChemCatChem 2 (2010) 41–47.
The authors thank the project PRIN 2008 Prot. 2008SXASBC for
financial support.
[40] J.M. Plainex, N. Coustel, B. Coq, V. Brotons, P.S. Kumbhar, R. Dutartre, P. Geneste,
P. Bernier, P.M. Ajayan, J. Am. Chem. Soc. 116 (1994) 7935–7936.
[
[
41] H. Gao, J. Zhao, J. Chem. Phys. 132 (1–7) (2010) 234704.
42] J.H. Bitter, J. Mater. Chem. 20 (2010) 7312–7321.
References
[43] X.X. Han, J.R. Li, R.X. Zhou, Chin. Chem. Lett. 20 (2009) 96–98.
[
[
[
44] S. Guo, K.Y. Liew, J. Li, J. Am. Oil Chem. Soc. 86 (2009) 1141–1147.
45] J. Kang, S. Zhang, Q. Zhang, Y. Wang, Angew. Chem. Int. Ed. 48 (2009) 2565–2568.
46] E. Asedegbega-Nieto, B. Bachiller-Baeza, D.G. Kuvshinov, F.R. Garcia-Garcia, E.
Chukanov, G.G. Kuvshinov, A. Guerrero-Ruiz, I. Rodriguez-Ramos, Carbon 46
[
[
[
[
[
[
[
[
[
1] M.M. Kirchhoff, Resour. Conserv. Recycl. 44 (2005) 237–243.
2] S.D. Wang, M.H. Liang, J.L. Zhang, Y. Wang, Curr. Org. Chem. 11 (2007) 299–314.
3] Y.C. Liu, C.Y. Huang, Y.W. Chen, J. Nanopart. Res. 8 (2006) 223–234.
4] V.L. Khilnani, S.B. Chandalia, Org. Proc. Res. Dev. 5 (2001) 257–262.
5] Q.X. Shi, R.W. Lu, Z.X. Zhang, D.F. Zhao, Green Chem. 8 (2006) 868–870.
6] X. Yan, J. Sun, Y. Wang, J. Yang, J. Mol. Catal. A 252 (2006) 17–22.
7] R. Baltzly, A.P. Phillips, J. Am. Chem. Soc. 68 (1946) 261–265.
(
2008) 1046–1052.
[
[
47] A. Solhy, B.F. Machado, J. Beausoleil, Y. Kihn, F. Goncalves, M.F.R. Pereira, J.J.M.
Orfao, J.L. Figueiredo, J.L. Faria, P. Serp, Carbon 46 (2008) 1194–1207.
48] F. Bensebaa, N. Patrito, Y. Le Page, P. L’Ecuyer, D. Wang, J. Mater. Chem. 14 (2004)
3378–3384.
8] H.-U. Blaser, H. Steiner, M. Studer, ChemCatChem 1 (2009) 210–221.
9] F. Cardenas-Lizana, S. Gomez-Quero, N. Perret, M.A. Keane, Gold Bull. 42 (2009)
[
[
[
[
[
49] W. Li, D. Li, W. Zhang, Y. Hu, Y. He, X. Fu, J. Phys. Chem. C 114 (2010) 2154–2159.
50] L. Ding, M. Zheng, A. Wang, T. Zhang, Catal. Lett. 135 (2010) 305–311.
51] Y.Y. Chu, Z.B. Wang, Z.Z. Jiang, D.M. Gu, G.P. Yin, Fuel Cells 10 (2010) 914–919.
52] J. Okal, Catal. Commun. 11 (2010) 508–512.
1
24–132.
[10] M. Pietrowski, M. Wojciechowska, Catal. Today 142 (2009) 211–214.
[11] H. Ma, K. Sun, Y. Li, X. Xu, Catal. Commun. 10 (2009) 1363–1366.
[12] F. Wang, J. Liu, X. Xu, Chem. Commun. (2008) 2040–2042.
53] P. Nekooi, M.K. Amini, Electrochim. Acta 55 (2010) 3286–3294.