|
|
|
| A catalyst-free novel synthesis of diethyl carbonate from ethyl carbamate in supercritical ethanol |
| Li-Cai Zhao, Zhi-Qiang Hou, Chun-Ze Liu, Yuan-Yuan Wang, Li-Yi Dai |
| Department of Chemistry, East China Normal University, Shanghai 200241, China |
|
|
|
|
Abstract Diethyl carbonate has been synthesized via the alcoholysis of ethyl carbamate in supercritical ethanol under catalyst-free conditions. The influences of various parameters such as reaction temperature, reaction time, reaction pressure, ethanol/ethyl molar ratios and reaction loading volume on the yield of DEC were studied systematically. The experimental results indicated that the alcoholysis of ethyl carbamate was greatly improved in supercritical ethanol. The optimal reaction conditions were as follows: a reaction temperature of 573 K, a reaction time of 30 min, a reaction pressure of 13.2 MPa, an ethanol/ethyl carbamate molar ratio of 10 and a reactor loading volume of 285 μL respectively. The optimal yield of DEC was 22.9%.
|
|
Received: 21 January 2014
Published: 13 May 2014
|
|
Corresponding Authors:
Yuan-Yuan Wang, Li-Yi Dai
E-mail: 48387162@qq.com
|
|
|
|
| [13] |
H.L. An, X.Q. Zhao, L. Guo, et al., Synthesis of diethyl carbonate from ethyl carbamate and ethanol over ZnO-PbO catalyst, Appl. Catal. A. 433/434 (2012) 229-235.
|
| [15] |
M.M. Gui, K.T. Lee, S. Bhatia, Supercritical ethanol technology for the production of biodiesel: process optimization studies, J. Supercrit. Fluids 49 (2009) 286-292.
|
| [2] |
J.X. Zhen, S.Y. Hua, C.S. Hua, Novel synthesis of diethyl carbonate over palladium/ MCM-41 catalysts, Catal. Lett. 69 (2000) 153-156.
|
| [9] |
J. Sun, B. Yang, H. Lin, A semi-continuous process for the synthesis of methyl carbamate from urea and methanol, Chem. Eng. Technol. 27 (2004) 435-439.
|
| [19] |
J. Lu, E.C. Boughner, Nearcritical and supercritical ethanol as a benign solvent: polarity and hydrogen-bonding, Fluid Phase Equilib. 198 (2002) 37-49.
|
| [6] |
H. Krimm, H.J. Buysch, H. Rudolph, Process for the preparation of dialkyl carbonates, U.S. Patent 4,307,032, Dec. 22, 1981
|
| [12] |
H.L. Zhao, X.Q. Zhao, H.L. An, et al., Synthesis of diethyl carbonate from ethyl carbamate and ethanol over leadoxide catalyst, Petrochem. Technol. 38 (2009) 139-144.
|
| [10] |
C.C. Wu, X.Q. Zhao, Y.J. Wang, Effect of reduction treatment on catalytic performance of Zn-based catalyst for the alcoholysis of urea to dimethyl carbonate, Catal. Commun. 6 (2005) 694-698.
|
| [11] |
D.P. Wang, B.L. Wang, X.W. Zhai, et al., Synthesis of diethyl carbonate by catalytic alcoholysis of urea, Fuel Process. Technol. 88 (2007) 807-812.
|
| [14] |
G. Brunner, Applications of supercritical fluids, Annu. Rev. Chem. Biomol. Eng. 1 (2010) 321-342.
|
| [17] |
G. Madras, C. Kolluru, R. Kumar, Synthesis of biodiesel in supercritical fluids, Fuel 83 (2004) 2029-2033.
|
| [20] |
P. Lalanne, J.M. Andanson, J.C. Soetens, et al., Hydrogen bonding in supercritical ethanol assessed by infrared and Raman spectroscopies, J. Phys. Chem. A 108 (2004) 3902-3909.
|
| [3] |
T.J. Bruno, A. Wolk, A. Naydich, et al., Composition-explicit distillation curves for mixtures of diesel fuel with dimethyl carbonate and diethyl carbonate, Energy Fuels 23 (2009) 3989-3997.
|
| [4] |
A.A.G. Shaikh, Organic carbonates, Chem. Rev. 96 (1996) 951-976.
|
| [8] |
M.H. Wang, N. Zhao, W. Wei, et al., Synthesis of dimethyl carbonate from urea and methanol over ZnO, Ind. Eng. Chem. Res. 44 (2005) 7596-7599.
|
| [16] |
H. Jie, H. Ke, Z. Qing, et al., Study on depolymerization of polycarbonate in supercritical ethanol, Polym. Degrad. Stab. 91 (2006) 2307e2314.
|
| [1] |
B.C. Dunn, C. Guenneau, S.A. Hilton, et al., Production of diethyl carbonate from ethanol and carbon monoxide over a heterogeneous catalyst, Energy Fuels 16 (2002) 177-181.
|
| [7] |
W.B. Zhao, W.C. Peng, D.F. Wang, et al., Zinc oxide as the precursor of homogenous catalyst for synthesis of dialkyl carbonate from urea and alcohols, Catal. Commun. 10 (2009) 655-658.
|
| [18] |
D. Dellis, M. Chalaris, J. Samios, Pressure and temperature dependence of the hydrogen bonding in supercritical ethanol: a computer simulation study, J. Phys. Chem. B 109 (2005) 18575-18590.
|
| [21] |
Y.Y. Gao, W.C. Peng, N. Zhao, et al., A DFT study on the reaction mechanism for dimethyl carbonate synthesis from methyl carbamate and methanol, J. Mol. Catal. A: Chem. 351 (2011) 29-40.
|
| [5] |
P.B. Zhang, Z. Zhang, S.P. Wang, et al., A new type of catalyst PdCl2/Cu-HMS for synthesis of diethyl carbonate by oxidative carbonylation of ethanol, Catal. Commun. 8 (2007) 21-26.
|
|
|
|
