Condensed Phase Ethanol Conversion to Higher Alcohols Tyler L. Jordison, Carl T. Lira, and Dennis J. Miller Department of Chemical Engineering and Materials Science Michigan State University Email: millerd@egr.msu.edu Phone: (517) 353-3928 Supporting Information
Figure S1. Experimental ethanol vapor pressure from the Parr 300ml reactor. 1 A. Rationale for Choice of SR-Polar EOS The Peng-Robinson-Wong-Sandler (PRWS), predictive Soave-Redlich-Kwong (PSRK), and Schwartzentruber--Renon (SR-Polar) equations of state were chosen for initial model screening. These equations of state are known for accurate prediction of vapor pressures because they incorporate the acentric (ω) factor with the critical point (T c, P c ). 2 For the PRWS, three alpha functions were tested: the standard PR alpha, Boston-Mathias, and Schwartzentruber. The PRWS and PSRK equations of state had the lowest average error in prediction of vapor pressures (2.1%) of the three EOS (Table S1). However, the Schwartzentruber-Renon- (SR)-Polar EOS was chosen because it offers the advantage of a temperature dependent molar volume translation parameter, while still giving excellent agreement of ethanol vapor pressure with experimental data (Figure S2). The SR-Polar EOS is also recommended for highly non-ideal systems at high temperatures and pressures. This is needed since predictions of liquid phase density for pure components with an equation of state deviate from experimental data at the near critical region. 2
Figure S2. Experimental ethanol vapor pressure data compared with vapor pressures predicted by the Peng Robinson and SR Polar equations of state. 3 Table S1. Error in vapor pressure calculated by PRWS, PSRK, and SR-Polar equations of state. PRWS-α 1 denotes standard PR, PRWS-α 2 denotes Boston Mathias, and PRWS-α 3 denotes Schwartszentruber. 3 PRWS-α 1 PRWS-α 2 PRWS-α 3 PSRK SR-Polar Ethanol 1.3 1.1 12.5 0.9 0.9 1-Butanol 15.5 0.8 0.9 1.0 0.8 1-Hexanol 35.9 6.2 5.7 5.9 7.2 Water 4.9 0.4 0.4 0.4 0.5 Average Abs % error 14.4 2.1 4.9 2.1 2.4
B. Parameters for SR-Polar EOS and comparison with literature data Table S2. Binary parameters for the ethanol Guerbet system Binary ka,ij0 ka,ij1 ka,ij2 lij0 lij2 Abs. Avg. Err. % (T. range) Ref Ethanol/CO2* -0.100 40.3 (304 K-453 K) 4-6 Ethanol/1-Butanol 0.047-15.249 1.0 (323 K-403 K) 7 Ethanol/Water -0.004-33.871 3.3 (298 K-473 K) 8,9 1-Butanol/CO2 0.078 24.9 (313 K-430 K) 10-12 1-Butanol/Water 0.131-81.051 0.211 58.836 1.5 (323 K-403 K) 7 13 Ethanol/CH4* -2.362 0.0047 38.4 (398 K-498 K) 14 Water/CO2-0.261 0.0006 20.6 (383 K-523 K) * The ethanol/ch 4 and ethanol/co 2 binary parameters were adjusted to our experimental data. The avg. error % was 18% with fitted Aspen NIST data for ethanol/ch 4, but increased to 38% with parameter adjustment. The avg. error % was 6.5% with fitted Aspen NIST data for ethanol/co 2, but increased to 40% with parameter adjustment. Table S3. Volume translation constants are listed for alcohols, water, methane, and CO 2. The (*) indicates translation constant was fit to binary with ethanol and not pure component data. 3 Component c 0i (m 3 /kmol) c 1i (m 3 /kmol) c 2i (m 3 /kmol) Avg. Abs Error (%) Ethanol 7.00E-03 2.50E-03 4.50E-02 3.8 1-Butanol 7.00E-03 2.60E-03 3.00E-03 0.6 1-Hexanol 1.10E-02 3.00E-03 0.8 Water 5.00E-03 7.97E-04 1.5 Methane* -1.20E-01 CO2* -3.00E-02 Figure S3. Predicted phase equilibria for ethanol-ch 4 is shown with the regressed, temperature dependent ka EtOH- CH4 and with the ka EtOH-CH4 adjusted to fit our validation experiments. 13
3, 13 Figure S4. SR-Polar translated density predictions are compared with experimental data. C. Temperature Programmed Desorption Profiles for CO 2 and NH 3 Figure S5. TPD profiles are shown for NH 3 and CO 2. The dashed lines separate site strength zones (weak, medium, strong).
D. Reaction Equilibria Gas-phase equilibrium constants are shown in Table S4 for reactions taking place in the ethanol Guerbet system. The equilibrium constant for ethanol dehydrogenation is 0.08 at 230 o C, and the equilibrium constant for the Tischenko reaction is 830. Table S4. Gas phase enthalpies and free energies of formation (298 K) and equilibrium constants at 503 K 1 H o r G r (kj/mol) (kj/mol) Ke V Reaction (298K) (298K) (503K) Ethanol Acetaldehyde + H 2 60.67 34.71 8.21E-02 2 Ethanol 1-Butanol + H 2 O -49.39-43.38 2.21E+04 Ethanol + 1-Butanol 1-Hexanol +H 2 O -70.44-45.08 2.90E+04 2 Acetaldehyde Ethyl Acetate -112.09-62.12 8.28E+02 2 Ethanol Diethyl Ether + H 2 O -38.88-13.89 8.09E+00 2 Ethanol 3 CH 4 + CO 2-163.26-210.47 2.46E+26
E. Flow diagram for SR-Polar EOS Application to Batch Reactions Figure S6. Flowsheet for SR-Polar model application to reaction data.
F. Supplementary References (1) Yaws, C. L.: Yaws' Critical Property Data for Chemical Engineers and Chemists. Knovel, 2012. (2) Elliot, J. R.; Lira, C. T.: Introductory Chemical Engineering Thermodynamics; 2nd ed.; Prentice Hall: Upper Saddle River, NJ, 2009. (3) Inc, A. T.: Aspen Properties 8.2. Burlington, MA, 2013. (4) Knez, Z.; Skerget, M.; Ilic, L.; Luetge, C.: Vapor-liquid equilibrium of binary CO2-organic solvent systems (ethanol, tetrahydrofuran, ortho-xylene, meta-xylene, para-xylene). Journal of Supercritical Fluids 2008, 43, 383-389. (5) Takishima, S.; Saiki, K.; Arai, K.; Saito, S. J.: Phase equilibria for the carbon dioxide-ethanol-water system. Chem. Eng. Jpn. 1986, 19, 48. (6) Zhu, H. G.; Tian, Y. L.; Chen, L.; Feng, J. J.; Fu, H. F.: Studies on vapor-liquid phase equilibria for SCF CO2+CH3OH and SCF CO2+C2H5OH systems. Chemical Journal of Chinese Universities-Chinese 2002, 23, 1588-1591. (7) Kharin, S. E.; Perelygin, V. M.; Remizov, G. P. I.; Zaved., V. U.: Liquid-vapor Phase Equilibriums in Ethanol-n-butanol and Water - n-butanol systems. Khim. Khim. Tekhnol. 1969, 12, 424-428. (8) Niesen, V.; Palavra, A.; Kidnay, A. J.; Yesavage, V. F.: An Apparatus for Vapor- Liquid-Equilbrium at Elevated-Temperatures and Pressures and Selected Results for the Water Ethanol and Methanol Ethanol Systems. Fluid Phase Equilibria 1986, 31, 283-298. (9) Nikolskaya, A. V.; Khim., Z. F.: 1946, 20, 421. (10) Elizalde-Solis, O.; Galicia-Luna, L. A.; Camacho-Camacho, L. E.: High-pressure vapor-liquid equilibria for CO2 plus alkanol systems and densities of n-dodecane and n- tridecane. Fluid Phase Equilibria 2007, 259, 23-32. (11) Silva-Oliver, G.; Galicia-Luna, L. A.: Vapor liquid equilibria near critical point and critical points for the CO2+1-butanol and CO2+2-butanol systems at temperatures from 324 to 432 K. Fluid Phase Equilibria 2001, 182, 145-156. (12) Yun, Z.; Shi, M.; Shi, J.: High Pressure Vapor-Liquid Phase Equilibrium for Carbon Dioxide-n-butanol and Carbon Dioxide-i-Butanol. Ranliao Huaxue Xuebao 1996, 24(1), 87-92. (13) Brunner, E.; Hultenschmidt, W.: Fluid Mixtures at High-Pressures.8. Isothermal Phase-Equilibria in the Binary - Mixtures - (Ethanol+Hydrogen or Methane or Ethane). Journal of Chemical Thermodynamics 1990, 22, 73-84. (14) Takenouchi, S.; Kennedy, G. C.: The Binary System H2O-CO2 at High Temperatures and Pressures. Am. J. Sci. 1964, 262, 1055-1074.