Thermodynamic analysis of ethanol synthesis from hydration of ethylene coupled with a sequential reaction

Abstract

Coal-based ethanol production by hydration of ethylene is limited by the low equilibrium ethylene conversion at elevated temperature. To improve ethylene conversion, coupling hydration of ethylene with a potential ethanol consumption reaction was analyzed thermodynamically. Five reactions have been attempted and compared: (1) dehydration of ethanol to ethyl ether ({\mathrm{2C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}\mathrm{OH}\iff{\mathrm{C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{OC}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{+H}}_{\mathrm{2}}\mathrm{O}), (2) dehydrogenation of ethanol to acetaldehyde ({\mathrm{C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}\mathrm{OH}\iff {\mathrm{CH}}_{\mathrm{3}}{\mathrm{CHO+H}}_{\mathrm{2}}), (3) esterification of acetic acid with ethanol ({\mathrm{C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{OH+CH}}_{\mathrm{3}}\mathrm{COOH}\iff {\mathrm{CH}}_{\mathrm{3}}{\mathrm{COOC}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{+H}}_{\mathrm{2}}\mathrm{O}), (4) dehydrogenation of ethanol to ethyl acetate ({\mathrm{2C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}\mathrm{OH}\iff {\mathrm{CH}}_{\mathrm{3}}{\mathrm{COOC}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{+2H}}_{\mathrm{2}}), and (5) oxidative dehydrogenation of ethanol to ethyl acetate ({\mathrm{2C}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{OH+O}}_{\mathrm{2}}\iff {\mathrm{CH}}_{\mathrm{3}}{\mathrm{COOC}}_{\mathrm{2}}{\mathrm{H}}_{\mathrm{5}}{\mathrm{+2H}}_{\mathrm{2}}\mathrm{O}). The equilibrium constants and equilibrium distributions of the coupled reactions were calculated and the effects of feed composition, temperature and pressure upon the ethylene equilibrium conversion were examined. The results show that dehydrogenation of ethanol to acetaldehyde has little effect on ethylene conversion, whereas for dehydrogenation of ethanol to acetaldehyde and ethyl acetate, ethylene conversion can be improved from 8% to 12.8% and 18.5%, respectively, under conditions of H₂O/C₂H₄ = 2, 10 atm and 300°C. The esterification of acetic acid with ethanol can greatly enhance the ethylene conversion to 22.5%; in particular, ethylene can be actually completely converted to ethyl acetate by coupling oxidative dehydrogenation of ethanol.

Graphical abstract

Keywords

ethylene / ethanol / thermodynamics / coupling

References

[1] Ni M, Leung D Y C, Leung M K H. A review on reforming bio-ethanol for hydrogen production. International Journal of Hydrogen Energy, 2007, 32(15): 3238–3247

[2] Al-Hasan M. Effect of ethanol-unleaded gasoline blends on engine performance and exhaust emission. Energy Conversion and Management, 2003, 44(9): 1547–1561

[3] Hansen A C, Zhang Q, Lyne P W L. Ethanol–diesel fuel blends––a review. Bioresource Technology, 2005, 96(3): 277–285

[4] Dien B S, Cotta M A, Jeffries T W. Bacteria engineered for fuel ethanol production: Current status. Applied Microbiology and Biotechnology, 2003, 63(3): 258–266

[5] Gnansounou E, Dauriat A. Techno-economic analysis of lignocellulosic ethanol: A review. Bioresource Technology, 2010, 101(13): 4980–4991

[6] Haider M A, Gogate M R, Davis R J. Fe-promotion of supported Rh catalysts for direct conversion of syngas to ethanol. Journal of Catalysis, 2009, 261(1): 9–16

[7] Pan X, Fan Z, Chen W, Ding Y, Luo H, Bao X. Enhanced ethanol production inside carbon-nanotube reactors containing catalytic particles. Nature Materials, 2007, 6(7): 507–511

[8] Kitson M, Williams P. Catalyzed hydrogenation of carboxylic acids and their anhydrides to alcohols and/or esters. US Patent, 4985572, 1991-01-15

[9] Xingang L, Xiaoguang S, Yi Z, Takashi I, Ming M, Yisheng T, Noritatsu T. Direct synthesis of ethanol from dimethyl ether and syngas over combined H-Mordenite and Cu/ZnO catalysts. ChemSusChem, 2010, 3(10): 1192–1199

[10] Llano-Restrepo M, Muñoz-Muñoz Y M. Combined chemical and phase equilibrium for the hydration of ethylene to ethanol calculated by means of the Peng-Robinson-Stryjek-Vera equation of state and the Wong-Sandler mixing rules. Fluid Phase Equilibria, 2011, 307(1): 45–57

[11] Ding Y. Research progress of synthesis of ethanol and mixed high carbon primary alcohols from syngas derived from coal. Coal Chemical Industry, 2018, 46(1): 1–5

[12] Castellanos-Beltran I J, Assima G P, Lavoie J M. Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst. Frontiers of Chemical Science and Engineering, 2018, 12(2): 226–238

[13] Cai D, Cui Y, Jia Z, Wang Y, Wei F. High-precision diffusion measurement of ethane and propane over SAPO-34 zeolites for methanol-to-olefin process. Frontiers of Chemical Science and Engineering, 2018, 12(1): 77–82

[14] Gilliland E R, Gunness R C, Bowles V O. Free energy of ethylene hydration. Industrial & Engineering Chemistry, 1936, 28(3): 370–372

[15] Ushikubo T. Recent topics of research and development of catalysis by niobium and tantalum oxides. Catalysis Today, 2000, 57(3): 331–338

[16] Katada N, Iseki Y, Shichi A, Fujita N, Ishino I, Osaki K, Torikai T, Niwa M. Production of ethanol by vapor phase hydration of ethene over tungsta monolayer catalyst loaded on titania. Applied Catalysis A, General, 2008, 349(1): 55–61

[17] Towler G, Lynn S. Novel applications of reaction coupling: Use of carbon dioxide to shift the equilibrium of dehydrogenation reactions. Chemical Engineering Science, 1994, 49(16): 2585–2591

[18] Sun A, Qin Z, Wang J. Reaction coupling of ethylbenzene dehydrogenation with water-gas shift. Applied Catalysis A, General, 2002, 234(1): 179–189

[19] Qin Z, Liu J, Sun A, Wang J. Reaction coupling in the new processes for producing styrene from ethylbenzene. Industrial & Engineering Chemistry Research, 2003, 42(7): 1329–1333

[20] Sun A, Qin Z, Wang J. Reaction coupling of ethylbenzene dehydrogenation with nitrobenzene hydrogenation. Catalysis Letters, 2002, 79(1): 33–37

[21] Abashar M E E. Coupling of ethylbenzene dehydrogenation and benzene hydrogenation reactions in fixed bed catalytic reactors. Chemical Engineering and Processing: Process Intensification, 2004, 43(10): 1195–1202

[22] Perry R H. Perry’s Chemical Engineers’ Handbook. 7th ed. New York: McGraw-Hill, 1999, 230–650

[23] Sanders F J, Dodge B F. Catalytic vapor-phase hydration of ethylene. Industrial & Engineering Chemistry, 1934, 26(2): 208–214

[24] Cope C S. Equilibria in the hydration of ethylene and of propylene. AIChE Journal. American Institute of Chemical Engineers, 1964, 10(2): 277–281

[25] Garbarino G, Riani P, Villa García M, Finocchio E, Sánchez Escribano V, Busca G. A study of ethanol conversion over zinc aluminate catalyst. Reaction Kinetics, Mechanisms and Catalysis, 2018, 124(2): 503–522

[26] Guan Y, Hensen E J M. Ethanol dehydrogenation by gold catalysts: The effect of the gold particle size and the presence of oxygen. Applied Catalysis A, General, 2009, 361(1-2): 49–56

[27] Rodriguez-Gomez A, Holgado J P, Caballero A. Cobalt carbide identified as catalytic site for the dehydrogenation of ethanol to acetaldehyde. ACS Catalysis, 2017, 7(8): 5243–5247

[28] Liu P, Li T, Chen H, Hensen E J M. Optimization of Au⁰–Cu⁺ synergy in Au/MgCuCr₂O₄ catalysts for aerobic oxidation of ethanol to acetaldehyde. Journal of Catalysis, 2017, 347: 45–56

[29] He R, Zou Y, Dong Y, Muhammad Y, Subhan S, Tong Z. Kinetic study and process simulation of esterification of acetic acid and ethanol catalyzed by. Chemical Engineering Research & Design, 2018, 137: 235–245

[30] Nielsen M, Junge H, Kammer A, Beller M. Towards a green process for bulk-scale synthesis of ethyl acetate: Efficient acceptorless dehydrogenation of ethanol. Angewandte Chemie International Edition, 2012, 51(23): 5711–5713

[31] McCullough L R, Cheng E S, Gosavi A A, Kilos B A, Barton D G, Weitz E, Kung H H, Notestein J M. Gas phase acceptorless dehydrogenative coupling of ethanol over bulk MoS₂ and spectroscopic measurement of structural disorder. Journal of Catalysis, 2018, 366: 159–166

[32] Lin T B, Chung D L, Chang J R. Ethyl acetate production from water-containing ethanol catalyzed by supported Pd catalysts: Advantages and disadvantages of hydrophobic supports. Industrial & Engineering Chemistry Research, 1999, 38(4): 1271–1276

[33] Jørgensen B, Egholm Christiansen S, Dahl Thomsen M L, Christensen C H. Aerobic oxidation of aqueous ethanol using heterogeneous gold catalysts: Efficient routes to acetic acid and ethyl acetate. Journal of Catalysis, 2007, 251(2): 332–337

[34] Weinstein R D, Ferens A R, Orange R J, Lemaire P. Oxidative dehydrogenation of ethanol to acetaldehyde and ethyl acetate by graphite nanofibers. Carbon, 2011, 49(2): 701–707

Acknowledgements

This work is supported by the National Key Research and Development Program of China (Grant No. 2018YFB0604802), the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA21020500), the National Natural Science Foundation of China (Grant Nos. U1862101 and 21773281), the CAS/SAFEA International Partnership Program for Creative Research Teams (No. 2015YC901) and Natural Science Foundation of Shanxi Province of China (No. 201601D202014).

RIGHTS & PERMISSIONS

2019 Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature