Global Kinetics of Direct Dimethyl Ether Synthesis Process from Syngas in Slurry Reactor over a Novel Cu-Zn-Al-Zr Slurry Catalyst

Authors: Zhen Chen, Haitao Zhang, Weiyong Ying, Dingye Fang

Abstract:

The direct synthesis process of dimethyl ether (DME) from syngas in slurry reactors is considered to be promising because of its advantages in caloric transfer. In this paper, the influences of operating conditions (temperature, pressure and weight hourly space velocity) on the conversion of CO, selectivity of DME and methanol were studied in a stirred autoclave over Cu-Zn-Al-Zr slurry catalyst, which is far more suitable to liquid phase dimethyl ether synthesis process than bifunctional catalyst commercially. A Langmuir- Hinshelwood mechanism type global kinetics model for liquid phase DME direct synthesis based on methanol synthesis models and a methanol dehydration model has been investigated by fitting our experimental data. The model parameters were estimated with MATLAB program based on general Genetic Algorithms and Levenberg-Marquardt method, which is suitably fitting experimental data and its reliability was verified by statistical test and residual error analysis.

Keywords: alcohol/ether fuel, Cu-Zn-Al-Zr slurry catalyst, global kinetics, slurry reactor

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1085064

References:

[1] H.-T. Zhang, D.-Y. Fang, "Dimethyl ether directly synthesizing from syngas," Chemical Industry and Engineering Progress, vol. 21, no. 2, pp. 97-10, Feb. 2002.
[2] J. Ere├▒a, R. Garo├▒a, J. M. Arandes, A.T. Aguayo, J. Bilbao, "Effect of operating conditions on the synthesis of dimethyl ether over CuO-ZnO-Al2O3/NaHZSM-5 bifunctional catalyst," Catal. Today, vol. 107-108, pp. 467-473, Oct. 2005.
[3] A.T. Aguayo, J. Ere├▒a, D. Mier, J. M.Arandes, M. Olazar, J. Bilbao, "Kinetic modeling of dimethyl ether synthesis in a single step on a CuO-ZnO-Al2O3/╬│-Al2O3 catalyst," Ind. Eng. Chem. Res., vol. 46, no. 17, pp. 5522-5530, July. 2007.
[4] Z.-L. Wang, J.-F. Wang, J. Diao, Y. Jin, "The synergy effect of process coupling for dimethyl ether synthesis in slurry reactor," Chemical Reaction Engineering and Technology, vol. 17, no. 3, pp. 233- 237, Sept. 2001.
[5] A. T. Aguayo, J. Ere├▒a, I. Sierra, M. Olazar, J. Bilbao, "Deactivation and regeneration of hybrid catalysts in the single-step synthesis of dimethyl ether from syngas and CO2," Catalysis Today, vol. 106, no. 1-4, pp. 265-270, Oct. 2005.
[6] D. Song, W. Cho, G. Lee, D. K. Park, E. S. Yoon, "Numerical analysis of a pilot-scale fixed-bed reactor for dimethyl ether (DME) synthesis," Ind. Eng. Chem. Res., vol. 47, no. 13, pp. 4553-4559 May. 2008.
[7] W.-Z. Lu, L.-H. Teng, W.-D. Xiao, "Simulation and experiment study of dimethyl ether synthesis from syngas in a fluidized-bed reactor," Chem. Eng. Sci., vol. 59, no.22-23, pp.5455-5464, Nov-Dec. 2004.
[8] K. L. Ng, D. Chadwick, B. A. Toseland, "Kinetics and modeling of dimethyl ether synthesis from synthesis gas," Chem. Eng. Sci., vol. 54, no. 15-16, pp. 3587- 3592, July.1999.
[9] X. D. Peng, B.A. Toseland, P. J. A. Tijim, "Kinetic Understanding of the Chemical Synergy under LPDME Conditions Once-through Applications," Chem. Eng. Sci., vol. 54, no.13-14, pp. 2787-2792, July. 1999.
[10] G. R. Moradi, J. Ahmadpour, F. Yaripour, "Intrinsic kinetics study of LPDME process from syngas over bi-functional catalyst," Chem. Eng. J., vol. 144, no.1, pp. 88-95, Oct. 2008.
[11] G. H. Graaf, E. J. Stamhuis, A. A. C. M. beenackers, "Kinetics of low pressure methanol synthesis," Chem. Eng. Sci., vol. 43, no.12, pp. 3185- 3195, July .1988.
[12] G. Bercic, J. Levec, "Intrinsic and global reaction rate of methanol dehydration over ╬│-Al2O3 pellets," Ind. Eng. Chem. Res., vol. 31, no.4, pp. 1035- 1040, Apr.1992.
[13] Z.-G. Nie, H.-W. Liu, D.-H. Liu, W.-Y. Ying, D.-Y.Fang, "The global kinetics of synthesis of dimethyl ether from syngas containing N2 over bifunctional catalyst," Chemical Reaction Engineering and Technology, vol. 20, no. 1, pp. 1-7, Mar. 2004.
[14] D.-H. Liu, X. Hua, D.-Y. Fang, "Mathematical Simulation and Design of three-phase bubble column reactor for direct synthesis of dimethyl ether from syngas," Journal of Natural Gas Chemistry, vol. 16, no.2, pp. 193-199, Apr. 2007.
[15] Z.-H. Gao, W. Huang, J.-Y. Wang, L.-H. Yin, K.-C. Xie, "Complete liquid-phase preparation and characterization of Cu-Zn-Al-Zr slurry catalysts for synthesis of dimethyl ether," Acta Chimica Sinica, vol. 66, no. 3, pp. 295-300, Feb. 2008.
[16] W.-D. Song, B.-C. Zhu, Z.-C. Luo, L.-B. Yu, G.-X. Feng, X. Xu, "Computation for heat of reaction and equilibrium constant of methanol synthesis under pressure by using SHBWR equation of state," Journal of East China University of Science and Technology, vol. 17, no. 1, pp. 11-24, Jan. 1981.
[17] Q. Zhang, J. Yang, W.-Y. Ying, D.-Y.Fang, "Calculation of equilibrium conversion and selectivity for dimethyl ether synthesis from syngas," Chemical Engineering, vol. 33, no. 2, pp. 64-68, Apr. 2005.