MKS Technical Note 05238

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1 Molecular Knowledge Systems, Inc. Page 1 of 5 MKS Technical Note Created: Updated: Cranium + Synapse Title: Verification of MultiBatchDS Export Capabilities Dissemination Classification: External-Public Contact: info@molecularknowledge.com Website: Summary MultiBatchDS is a batch distillation simulation program currently supported by the Vishwamitra Research Institute ( Cranium generates the data files needed by MultiBatchDS. These files include data values and parameters for the following physical properties: 1) Normal boiling point 2) Molecular weight 3) Liquid enthalpy 4) Vapor enthalpy 5) Vapor pressure 6) Liquid density In addition, Cranium generates a file containing the molecular structures of the exported chemicals dissected into UNIFAC groups. This report details the verification of these export capabilities. The MKS MultiBatchDS KB (updated ) was used to generate the five MultiBatchDS data files shown in Appendices A through E. 2.0 Constant Properties MultiBatchDS uses the pure.con data file to store values for the molecular weight, in units of g/mol, and the normal boiling point, in units of degrees K. Additional properties are displayed in the pure.con file, however, values for these properties are not currently exported. Appendix A shows the export file used for verification. Table 1 compares the exported physical property values with values taken from the literature [1]. Table 1: Comparison of Exported Constant Properties Chemical Mw (MKS) Mw (lit) Tb (MKS) Tb (lit) g / mol g / mol K K Acetone Acetonitrile Methanol n-butane n-hexane Only molecular structures were given for n-butane and n-hexane no other physical properties were added to the knowledge base for these compounds. Thus, all values shown for n-butane and n-hexane are estimated values. The values shown in Table 1 verify that the constant properties are being accurately exported to the pure.con data file.

2 Molecular Knowledge Systems, Inc. Page 2 of Liquid Density MultiBatchDS uses the pure.den data file to store parameter values for the liquid density in units of kg/m 3. These parameters are used with the following equation to generate density values. den 2 3 A BT CT DT (1) In Equation 1 density is in units of kg-mol / m 3 and temperature is in units of degrees K. A, B, C and D are the parameters written to the pure.den data file. Appendix B shows the export file used for verification. Table 2 compares several liquid density values for methanol calculated from exported parameters with values taken from the literature [1]. The agreement between the values verifies that the liquid density parameters are being accurately exported. Table 2: Comparison of Methanol Liquid Densities Temperature Liq Den (MKS) Liq Den (lit) K kg-mol / m 3 kg-mol / m Liquid and Vapor Enthalpy MultiBatchDS uses the pure.ent data file to store parameter values for the liquid and vapor enthalpy both in units of cal/g-mol. These parameters are used with the following equations to generate enthalpy values. H L AL BLT CLT DLT ELT (2) H V AV BV T CVT DV T EVT (3) A standard state of liquid at K is assumed. In Equations 2 and 3 enthalpy is in units of cal / g-mol and temperature is in units of degrees K. A, B, C and D are the parameters written to the pure.ent data file for both liquid and vapor phases. Although the liquid and vapor enthalpy can be calculated directly, the approach taken by the MultiBatchDS export code is to retrieve a value for the enthalpy of vaporization at K and parameter values for a polynomial fit of the liquid and vapor heat capacity. The heat capacity terms are then integrated and the coefficients written to the pure.ent data file. Appendix C shows the export file used for verification. Table 3 compares several enthalpy values for n- hexane at kpa calculated from exported parameters against values taken from the literature [1]. (The literature values were adjusted for differences in standard states.) The agreement between the values verifies that both the liquid and vapor enthalpy parameters are being accurately exported.

3 Molecular Knowledge Systems, Inc. Page 3 of 5 Table 3: Comparison of n-hexane Enthalpies Temperature H (MKS) H (lit) State K cal / g-mol cal / g-mol , , Liquid , , Liquid Liquid , , Liquid , , Liquid , , Vapor , , Vapor , , Vapor , , Vapor , , Vapor 5.0 Liquid Vapor Pressure MultiBatchDS uses the pure.par data file to store parameter values for the liquid vapor pressure. These parameters are used with the following equation to generate vapor pressure values. B A T C log P vp 10 (4) In Equations 4 vapor pressure is in units of mmhg and temperature is in units of degrees C. A, B and C are the parameters written to the pure.par data file. Appendix D shows the export file used for verification. Table 4 compares several vapor pressure values for acetonitrile calculated from exported parameters against values taken from the literature [1]. The agreement between the values verifies that both the vapor pressure parameters are being accurately exported. Table 4: Comparison of Liquid Vapor Pressures Temperature P vp (MKS) P vp (lit) C mmhg mmhg Molecular Structure MultiBatchDS uses the unifac.fil file to store molecular structure information in the form of UNIFAC groups. Four different sets of groups are used: 1) the original UNIFAC groups for VLE; 2) the UNIFAC groups for LLE; 3) the Lyngby version of UNIFAC groups for VLE; 4) the modified Dortmund version of UNIFAC groups for VLE. Appendix E shows the export file used for verification. Table 5 shows the group numbers for various groups in the different UNIFAC versions. Table 6 shows the group index and number of occurrences for each chemical in the example file. The structures all have been correctly dissected into groups.

4 Molecular Knowledge Systems, Inc. Page 4 of 5 Table 5: Group Indices for Various Groups in each UNIFAC Version Group VLE UNIFAC LLE UNIFAC LIN UNIFAC MOD UNIFAC -CH CH CO-CH OH Acetonitrile Methanol Table 6: Group Indices and Occurrences for each Example Chemical Chemical VLE UNIFAC LLE UNIFAC LIN UNIFAC MOD UNIFAC Acetone (1 1) (1 19) (1 1) (1 19) (1 1) (1 19) (1 1) (1 15) Acetonitrile (1 41) (1 41) (1 41) (1 34) Acetylene Methanol (1 16) (1 1) (1 14) (1 16) (1 13) n-butane (2 1) (2 2) (2 1) (2 2) (2 1) (2 2) (2 1) (2 2) n-hexane (2 1) (4 2) (2 1) (4 2) (2 1) (4 2) (2 1) (4 1) 7.0 References 1. NIST Chemistry WebBook. Accessed January Appendix A: Pure.con Export File The pure.con export file is a fixed format data file containing values for the molecular weight and normal boiling point. The contents of an example file are shown below. Because the file s width is greater than that of these pages, its font size has been significantly reduced. NAME MW OM Tc Pc Zc Vc Tb DIP. MOM. RAD. GYR. A26 (g/mole) (K) (atm) (cm3/mol) (K) (C*m) (m) Acetone Acetonitrile Acetylene Methanol n-butane n-hexane Appendix B: Pure.den Export File The pure.den export file is a fixed format data file containing parameter values for the liquid density. The contents of an example file are shown below. Because the file s width is greater than that of these pages, its font size has been reduced. Name A B C D Acetone e e e e-008 Acetonitrile e e e e-008 Acetylene e e e e-007 Methanol e e e e-006 n-butane e e e e-008 n-hexane e e e e-008

5 Molecular Knowledge Systems, Inc. Page 5 of 5 Appendix C: Pure.ent Export File The pure.ent export file is a fixed format data file containing parameter values for the liquid and vapor enthalpies. The contents of an example file are shown below. Because the file s width is greater than that of these pages, its font size has been significantly reduced. Name Vap A Vap B Vap C Vap D Vap E Liq A Liq B Liq C Liq D Liq E Acetone e e e e e e e e e e-008 Acetonitrile e e e e e-010 1E30 1E30 1E30 1E30 1E30 Acetylene e e e e e e e e e e-006 Methanol e e e e e e e e e e-021 n-butane e e e e e e e e e e-006 n-hexane e e e e e e e e e e-007 Appendix D: Pure.par Export File The pure.par export file is a fixed format data file containing parameter values for the liquid vapor pressure. The contents of an example file are shown below. Because the file s width is greater than that of these pages, its font size has been reduced. NAME NHY IMC MATHIAS-COPEMAN PAR. IAN ANTOA ANTOB ANTOC IDI Hvap Hf DIPPR Gf A8 CIF CIF C1 C2 C3 CIF (mm HG/C) CIF (cal/mol) --- (Kcal/mol) --- Acetone Acetonit Acetylen Methanol n-butane n-hexane Appendix E: Unifac.fil Export File The unifac.fil export file is a fixed format data file containing the group ids and occurrences of those UNIFAC groups comprising each chemical s molecular structure. The contents of an example file are shown below. Because the file s width is greater than that of these pages, its font size has been greatly reduced COMPONENT ORIGINAL UNIFAC (VLE) (UNIPAR.X80) ORIGINAL UNIFAC (LLE) (UNIPARL.X80) ORIGINAL UNIFAC (VLE, 2 PAR, LIN) (UNILIN.X80) MODIFIED UNIFAC (VLE, 3 PAR, MHV2) (UNIMOD.X80) Acetone , , , 0 0 0, Acetonitrile , , , , Acetylene , , , , Methanol , , , , n-butane , , , , n-hexane , , , ,

Homework Problem Set 6 Solutions

Chemistry 360 Dr. Jean M. Standard Homework Problem Set 6 Solutions 1. Determine the amount of pressure-volume work performed by 50.0 g of liquid water freezing to ice at 0 C and 1 atm pressure. The density