The knowledge of biodiesel density over large ranges
of temperature and pressure is important for predicting the behavior
of fuel injection and combustion systems in diesel engines, and for
the optimization of such systems. In this study, cottonseed oil was
transesterified into biodiesel and its density was measured at
temperatures between 288 K and 358 K and pressures between 0.1
MPa and 30 MPa, with expanded uncertainty estimated as ±1.6 kg⋅m-
3. Experimental pressure-volume-temperature (pVT) cottonseed data
was used along with literature data relative to other 18 biodiesels, in
order to build a database used to test the correlation of density with
temperarure and pressure using the Goharshadi–Morsali–Abbaspour
equation of state (GMA EoS). To our knowledge, this is the first that
density measurements are presented for cottonseed biodiesel under
such high pressures, and the GMA EoS used to model biodiesel
density. The new tested EoS allowed correlations within 0.2 kg·m-3
corresponding to average relative deviations within 0.02%. The built
database was used to develop and test a new full predictive model
derived from the observed linear relation between density and degree
of unsaturation (DU), which depended from biodiesel FAMEs
profile. The average density deviation of this method was only about
3 kg.m-3 within the temperature and pressure limits of application.
These results represent appreciable improvements in the context of
density prediction at high pressure when compared with other
equations of state.
[1] Pratas MJ, Oliveira MB, Pastoriza-Gallego MJ, Queimada AJ, Pineiro
MM, Coutinho JAP. High-Pressure Biodiesel Density: Experimental
Measurements, Correlation, and Cubic-Plus-Association Equation of
State (CPA EoS) Modeling. Energy Fuels 2011;25:3806–14.
[2] Tat ME, Van Gerpen JH. Speed of Sound and Isentropic Bulk Modulus
of Alkyl Monoesters at Elevated Temperatures and Pressures. J Am Oil
Chem Soc 2003;80:1249-56.
[3] Patil S, Akarte MM. Effect of Injection Pressure on CI Engine
Performance Fuelled with Biodiesel and its blends. International Journal
of Scientific & Engineering Research 2012;3:1-4.
[4] Çelik MB, Simsek D. The determination of optimum injection pressure
in an engine fuelled with soybean biodiesel/diesel blen. Thermal
Science. Doi 10.2298/TSCl12807023C.
[5] Liu HP, Strank S, Werst M, Hebner R, Osara J. Combustion emissions
modeling and testing of neat biodiesel fuels. Proceedings of the ASME
2010 4th International Conference on Energy Sustainability ES2010,
May 17-22, 2010, Phoenix, AZ USA.
[6] Ghurri A, Kim JD, Kim HG, Jung JY, Song KK. The effect of injection
pressure and fuel viscosity on the spray characteristics of biodiesel
blends injected into an atmospheric chamber. Journal of Mechanical
Science and Technology. 2012;26:2941-47.
[7] Seykens XLJ, Somers LMT, Baert RSG. Modeling of common rail fuel
injection system and influence of fluid properties on injection process.
Proceedings of VAFSEP 2004; 6-9 July 2004, Dublin, Ireland.
[8] Torres-Jimenez E, Svoljšak-Jerman M, Gregorc A, Lisec I, Dorado MP,
Kegl B. Physical and chemical properties of ethanol–biodiesel blends for
diesel engines. Energy Fuels 2010;24:2002–9.
[9] Enweremadu CC, Alamu OJ. Development and characterization of
biodiesel from shea nut butter. Int Agrophys 2010;24:29–34.
[10] Alptekin E, Canakci M. Characterization of the key fuel properties of
methyl ester–diesel fuel blends. Fuel 2009;88:75–80.
[11] Alptekin E, Canakci M. Determination of the density and the viscosities
of biodiesel–diesel fuel blends. Renew Energy 2008;33:2623–30.
[12] Doll KM, Sharma BK, Suarez PAZ, Erhan SZ. Comparing biofuels
obtained from pyrolysis, of soybean oil or soapstock, with traditional
soybean biodiesel: density, kinematic viscosity, and surface tensions.
Energy Fuels 2008;22:2061–6.
[13] Santos ICF, de Carvalho SHV, Solleti JI, Ferreira de La Salles W,
Teixeira da Silva de La Salles K, Meneghetti SMP. Studies of
Terminalia catappa l. oil: characterization and biodiesel production.
Biores Technol 2008;99:6545–9.
[14] Tiwari AK, Kumar A, Raheman H. Biodiesel production from jatropha
oil(Jatropha curcas) with high free fatty acids: an optimized process.
Biomass Bioenergy 2007;31:569–75.
[15] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Viscosities and
densities of binary and ternary blends of palm oil + palm biodiesel +
diesel fuel at different temperatures. J Chem Eng Data 2010;55:504–7.
[16] Huber ML, Lemmon EW, Kazakov A, Ott LS, Bruno TJ. Model for the
thermodynamic properties of a biodiesel fuel. Energy Fuels
2009;23:3790–7.
[17] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Density of palm
oil-based methyl ester. J Chem Eng Data 2008;53:877–80.
[18] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Densities of
ethyl esters produced from different vegetable oils. J Chem Eng Data
2008;53:2222–5.
[19] Tate RE, Watts KC, Allen CAW, Wilkie KI. The densities of three
biodiesel fuels at temperatures up to 300 ºC. Fuel 2006;85:1004–9.
[20] Tat ME, Van Gerpen JH. The specific gravity of biodiesel and its blends
with diesel fuel. J Am Oil Chem Soc 2000;77(2):115–9.
[21] Tat ME, Gerpen JH. Measurement of Biodiesel Speed of Sound and Its
Impact on Injection Timing. National Renewable Energy Laboratory
2003; NREL/SR-510-31462.
[22] Tat ME, Gerpen JH, Soylu S, Canakci M, Monyem A, Wormley S. The
speed of sound and isentropic bulk modulus of biodiesel at 21°C
from atmospheric pressure to 35 MPa. J Am Oil Chem Soc
2000;77:285-9.
[23] Nikolić BD, Kegl B, Marcović SD, Mitrović MS. Determining the speed
of sound, density and bulk modulus of rapeseed oil, biodiesel and diesel
fuel. Therm Science 2012;16, Suppl. 2: S569-S579.
[24] Aparicio C, Guignon B, Rodriguez-Anton LM, Sanz PD. Determination
of Rapseed Methyl Ester Oil Volumetric Properties in High Pressure
(0.1 to 350 MPa). J. Therm. Anal. Calorim. 2007; 89: 13–19.
[25] Dzida M, Prusakiewicz P. The effect of temperature and pressure on
thephysicochemical properties of petroleum diesel oil and biodiesel fuel.
Fuel 2008;87:1941–1948.
[26] Chhetri AB, Watts KC. Densities of canola, jatropha and soapnut
biodiesel at elevated temperatures and pressures. Fuel 2012;99:210–6.
[27] Schedemann A, Wallek T, Zeymer M, Maly M, Gmehling J.
Measurement and correlation of biodiesel densities at pressures up to
130 MPa. Fuel 2013;107:483–92.
[28] Dymond JH, Malhotra R. The Tait equation: 100 years on. Int. J.
Thermophys. 1988;9:941–51.
[29] Kontogeorgis GM, Michelsen ML, Folas GK, Derawi S, von Solms N,
Stenby EH. Ten years with the CPA (Cubic-Plus-Association) Equation
of State Part I (Pure Compounds and Self-Associating System). Ind.
Eng. Chem. Res. 2006;45: 4855–68.
[30] Kontogeorgis GM, Michelsen ML, Folas GK, Derawi S, von Solms N,
Stenby EH. Ten years with the CPA (Cubic-Plus-Association) Equation
of State Part II (Cross-Associating and Multicomponents System). Ind.
Eng. Chem. Res. 2006;45:4869–78.
[31] Schmid B, Gmehling J. From van der Waals to VTPR: the systematic
improvement of the van der Waals equation of state. J Supercritical
Fluids 2010;55:438–47.
[32] Weidlich U, Gmehling J. A modified UNIFAC model. 1. Prediction of
VLE, hE, and gamma infinite. Ind Eng Chem Res 1987;26(7):1372–81.
[33] Gross J, Sadowski G. Application of perturbation theory to a hard-chain
reference fluid: an equation of state for square-well chains. Fluid Phase
Equilibria. 2000; 168:183 - 199.
[34] Oliveira MB, Freitas SVD, Llovell F, Vega LF, Coutinho JAP.
Development of simple and transferable molecular models for biodiesel
production with the soft-SAFT equation of state, Chemical Engineering
Research and Design; 2014: DOI: 10.1016/j.cherd.2014.02.025.
[35] Dong NH, Thuy NT, Tho VDS. Predicting the temperature/pressure
dependent density of biodiesel fuels. Petrovietnam J. 2012; 10:46-58.
[36] Pratas MJ, Freitas SVD, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Biodiesel Density: Experimental Measurements and Prediction
Models. Energy Fuels 2011;25:2333–40.
[37] Meng X, Jia M., Wang T. Predicting biodiesel densities over a wide
temperature range up to 523 K. Fuel 2013;111:216–222.
[38] Spencer CF, Danner RP. Improved equation for prediction of saturated
liquid density. J Chem Eng Data 1972;17:236–41.
[39] Goharshadi EK, Morsali A, Abbaspour M. New regularities and an
equation of state for liquids Fluid Phase Equilib. 2005;230:170–75.
[40] Nogueira CA, Feitosa FX, Fernandes FAN, Santiago RS, Sant’Ana HB.
Densities and Viscosities of Binary Mixtures of Babassu Biodiesel +
Cotton Seed or Soybean Biodiesel at Different Temperatures, J. Chem.
Eng. Data 2010; 55:5305–10.
[41] Altin R., Çetinkaya S, Yücesu HS. The potential of using vegetable oil
fuels as fuel for diesel engines. Energ Convers Manage, 2001; 42(5):
529–538.
[42] Lopes DC, Neto AJS. Potential Crops for Biodiesel Production in Brazil:
A Review. World J Agric Sci 7 (2): 206-217, 2011.
[43] Rashid, U, Anwar F, Knothe G. Evaluation of biodiesel obtained from
cottonseed oil. Fuel Process Technol 200); 90(9):1157-1163.
[44] Sarada SN, Shailaja M, Raju AVSR, Radha KK. Optimization of
injection pressure for a compression ignition engine with cotton seed oil
as an alternate fuel, International Journal of Engineering, Science and
Technology, Vol. 2, No. 6, 2010, pp. 142-149.
[45] Carlos EF, Talavera-Prieto MC, Fonseca IMA, Portugal ATG, Ferreira
AGM. Measurements of pVT, viscosity, and surface tension of
trihexyltetradecylphosphonium tris(pentafluoroethyl)trifluorophosphate
ionic liquid and modelling with equations of state. J. Chem. Thermodyn
2012; 47: 183–196.
[46] Fluid properties for water, June 2014,
<http://webbook.nist.gov/chemistry/fluid/>.
[47] Private communication from Anton Parr, 2005.
[48] Sun TF, Ten Seldam CA, Kortbeek PJ, Trappeniers NJ, Biswas SN.
Acoustic and thermodynamic properties of ethanol from 273.15 to
333.15 K and up to 280 MPa. Phys Chem Liq 1988;18:107–16.
[49] Ramos MJ, Fernández CM, Casas A, Rodríguez L, Pérez A. Influence of
fatty acid composition of raw materials on biodiesel properties.
Bioresource Technol 2008;100:261–68.
[50] Mohibbe A, Amtul W, Nahar NM. Prospect and Potential of Fatty Acid
Methyl Esters of some Non-traditional Seeds Oils for use as Biodiesel in
India. Biomass Bioener 2005;29:293-302.
[51] Islam MA, Magnusson M, Brown RJ, Ayoko GA, Nabi N, Heimann K.
Microalgal Species Selection for Biodiesel Production Based on Fuel
Properties Derived from Fatty Acid Profiles. Energies 2013;6(11):5676-
702.
[52] ”EN 14214, Fatty acid methyl esters (FAME) for diesel engines,
Requirements and test methods.” European Committee for
Standardization: Management Centre, rue de Stassart 36, B-1050,
Brussels, 2003.
[53] Elbro HS, Fredenslund A, Rasmussen P. Group contribution method for
the prediction of liquid densities as a function of temperature for
solvents, oligomers, and polymers. Ind. Eng. Chem. Res. 1991;30:2576-
82.
[54] Ihmels EC, Gmehling J. Extension and Revision of the Group
Contribution Method GCVOL for the Prediction of Pure Compound
Liquid Densities. Ind. Eng. Chem. Res. 2003;42:408-12.
[55] Pratas MJ, Freitas S, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Densities and Viscosities of Fatty Acid Methyl and Ethyl Esters. J.
Chem. Eng. Data 2010; 55:3983-90.
[56] Pratas MJ, Freitas S, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Densities and Viscosities of Minority Fatty Acid Methyl and Ethyl
Esters Present in Biodiesel. J. Chem. Eng. Data 2011; 56: 2175–80.
[57] Ndiaye HI, Habrioux M, Coutinho JAP, Paredes MLL, Daridon JL.
Speed of sound, density, and derivative properties of ethyl myristate,
methyl myristate, and methyl palmitate under high pressure, J. Chem.
Eng. Data 2013; 58:1371-1377.
[58] Outcalt SL. Compressed-liquid density measurements of methyl oleate
and methyl linoleate, J. Chem. Eng. Data 2011; 56:4239-4243.
[1] Pratas MJ, Oliveira MB, Pastoriza-Gallego MJ, Queimada AJ, Pineiro
MM, Coutinho JAP. High-Pressure Biodiesel Density: Experimental
Measurements, Correlation, and Cubic-Plus-Association Equation of
State (CPA EoS) Modeling. Energy Fuels 2011;25:3806–14.
[2] Tat ME, Van Gerpen JH. Speed of Sound and Isentropic Bulk Modulus
of Alkyl Monoesters at Elevated Temperatures and Pressures. J Am Oil
Chem Soc 2003;80:1249-56.
[3] Patil S, Akarte MM. Effect of Injection Pressure on CI Engine
Performance Fuelled with Biodiesel and its blends. International Journal
of Scientific & Engineering Research 2012;3:1-4.
[4] Çelik MB, Simsek D. The determination of optimum injection pressure
in an engine fuelled with soybean biodiesel/diesel blen. Thermal
Science. Doi 10.2298/TSCl12807023C.
[5] Liu HP, Strank S, Werst M, Hebner R, Osara J. Combustion emissions
modeling and testing of neat biodiesel fuels. Proceedings of the ASME
2010 4th International Conference on Energy Sustainability ES2010,
May 17-22, 2010, Phoenix, AZ USA.
[6] Ghurri A, Kim JD, Kim HG, Jung JY, Song KK. The effect of injection
pressure and fuel viscosity on the spray characteristics of biodiesel
blends injected into an atmospheric chamber. Journal of Mechanical
Science and Technology. 2012;26:2941-47.
[7] Seykens XLJ, Somers LMT, Baert RSG. Modeling of common rail fuel
injection system and influence of fluid properties on injection process.
Proceedings of VAFSEP 2004; 6-9 July 2004, Dublin, Ireland.
[8] Torres-Jimenez E, Svoljšak-Jerman M, Gregorc A, Lisec I, Dorado MP,
Kegl B. Physical and chemical properties of ethanol–biodiesel blends for
diesel engines. Energy Fuels 2010;24:2002–9.
[9] Enweremadu CC, Alamu OJ. Development and characterization of
biodiesel from shea nut butter. Int Agrophys 2010;24:29–34.
[10] Alptekin E, Canakci M. Characterization of the key fuel properties of
methyl ester–diesel fuel blends. Fuel 2009;88:75–80.
[11] Alptekin E, Canakci M. Determination of the density and the viscosities
of biodiesel–diesel fuel blends. Renew Energy 2008;33:2623–30.
[12] Doll KM, Sharma BK, Suarez PAZ, Erhan SZ. Comparing biofuels
obtained from pyrolysis, of soybean oil or soapstock, with traditional
soybean biodiesel: density, kinematic viscosity, and surface tensions.
Energy Fuels 2008;22:2061–6.
[13] Santos ICF, de Carvalho SHV, Solleti JI, Ferreira de La Salles W,
Teixeira da Silva de La Salles K, Meneghetti SMP. Studies of
Terminalia catappa l. oil: characterization and biodiesel production.
Biores Technol 2008;99:6545–9.
[14] Tiwari AK, Kumar A, Raheman H. Biodiesel production from jatropha
oil(Jatropha curcas) with high free fatty acids: an optimized process.
Biomass Bioenergy 2007;31:569–75.
[15] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Viscosities and
densities of binary and ternary blends of palm oil + palm biodiesel +
diesel fuel at different temperatures. J Chem Eng Data 2010;55:504–7.
[16] Huber ML, Lemmon EW, Kazakov A, Ott LS, Bruno TJ. Model for the
thermodynamic properties of a biodiesel fuel. Energy Fuels
2009;23:3790–7.
[17] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Density of palm
oil-based methyl ester. J Chem Eng Data 2008;53:877–80.
[18] Baroutian S, Aroua MK, Raman AAA, Sulaiman NMN. Densities of
ethyl esters produced from different vegetable oils. J Chem Eng Data
2008;53:2222–5.
[19] Tate RE, Watts KC, Allen CAW, Wilkie KI. The densities of three
biodiesel fuels at temperatures up to 300 ºC. Fuel 2006;85:1004–9.
[20] Tat ME, Van Gerpen JH. The specific gravity of biodiesel and its blends
with diesel fuel. J Am Oil Chem Soc 2000;77(2):115–9.
[21] Tat ME, Gerpen JH. Measurement of Biodiesel Speed of Sound and Its
Impact on Injection Timing. National Renewable Energy Laboratory
2003; NREL/SR-510-31462.
[22] Tat ME, Gerpen JH, Soylu S, Canakci M, Monyem A, Wormley S. The
speed of sound and isentropic bulk modulus of biodiesel at 21°C
from atmospheric pressure to 35 MPa. J Am Oil Chem Soc
2000;77:285-9.
[23] Nikolić BD, Kegl B, Marcović SD, Mitrović MS. Determining the speed
of sound, density and bulk modulus of rapeseed oil, biodiesel and diesel
fuel. Therm Science 2012;16, Suppl. 2: S569-S579.
[24] Aparicio C, Guignon B, Rodriguez-Anton LM, Sanz PD. Determination
of Rapseed Methyl Ester Oil Volumetric Properties in High Pressure
(0.1 to 350 MPa). J. Therm. Anal. Calorim. 2007; 89: 13–19.
[25] Dzida M, Prusakiewicz P. The effect of temperature and pressure on
thephysicochemical properties of petroleum diesel oil and biodiesel fuel.
Fuel 2008;87:1941–1948.
[26] Chhetri AB, Watts KC. Densities of canola, jatropha and soapnut
biodiesel at elevated temperatures and pressures. Fuel 2012;99:210–6.
[27] Schedemann A, Wallek T, Zeymer M, Maly M, Gmehling J.
Measurement and correlation of biodiesel densities at pressures up to
130 MPa. Fuel 2013;107:483–92.
[28] Dymond JH, Malhotra R. The Tait equation: 100 years on. Int. J.
Thermophys. 1988;9:941–51.
[29] Kontogeorgis GM, Michelsen ML, Folas GK, Derawi S, von Solms N,
Stenby EH. Ten years with the CPA (Cubic-Plus-Association) Equation
of State Part I (Pure Compounds and Self-Associating System). Ind.
Eng. Chem. Res. 2006;45: 4855–68.
[30] Kontogeorgis GM, Michelsen ML, Folas GK, Derawi S, von Solms N,
Stenby EH. Ten years with the CPA (Cubic-Plus-Association) Equation
of State Part II (Cross-Associating and Multicomponents System). Ind.
Eng. Chem. Res. 2006;45:4869–78.
[31] Schmid B, Gmehling J. From van der Waals to VTPR: the systematic
improvement of the van der Waals equation of state. J Supercritical
Fluids 2010;55:438–47.
[32] Weidlich U, Gmehling J. A modified UNIFAC model. 1. Prediction of
VLE, hE, and gamma infinite. Ind Eng Chem Res 1987;26(7):1372–81.
[33] Gross J, Sadowski G. Application of perturbation theory to a hard-chain
reference fluid: an equation of state for square-well chains. Fluid Phase
Equilibria. 2000; 168:183 - 199.
[34] Oliveira MB, Freitas SVD, Llovell F, Vega LF, Coutinho JAP.
Development of simple and transferable molecular models for biodiesel
production with the soft-SAFT equation of state, Chemical Engineering
Research and Design; 2014: DOI: 10.1016/j.cherd.2014.02.025.
[35] Dong NH, Thuy NT, Tho VDS. Predicting the temperature/pressure
dependent density of biodiesel fuels. Petrovietnam J. 2012; 10:46-58.
[36] Pratas MJ, Freitas SVD, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Biodiesel Density: Experimental Measurements and Prediction
Models. Energy Fuels 2011;25:2333–40.
[37] Meng X, Jia M., Wang T. Predicting biodiesel densities over a wide
temperature range up to 523 K. Fuel 2013;111:216–222.
[38] Spencer CF, Danner RP. Improved equation for prediction of saturated
liquid density. J Chem Eng Data 1972;17:236–41.
[39] Goharshadi EK, Morsali A, Abbaspour M. New regularities and an
equation of state for liquids Fluid Phase Equilib. 2005;230:170–75.
[40] Nogueira CA, Feitosa FX, Fernandes FAN, Santiago RS, Sant’Ana HB.
Densities and Viscosities of Binary Mixtures of Babassu Biodiesel +
Cotton Seed or Soybean Biodiesel at Different Temperatures, J. Chem.
Eng. Data 2010; 55:5305–10.
[41] Altin R., Çetinkaya S, Yücesu HS. The potential of using vegetable oil
fuels as fuel for diesel engines. Energ Convers Manage, 2001; 42(5):
529–538.
[42] Lopes DC, Neto AJS. Potential Crops for Biodiesel Production in Brazil:
A Review. World J Agric Sci 7 (2): 206-217, 2011.
[43] Rashid, U, Anwar F, Knothe G. Evaluation of biodiesel obtained from
cottonseed oil. Fuel Process Technol 200); 90(9):1157-1163.
[44] Sarada SN, Shailaja M, Raju AVSR, Radha KK. Optimization of
injection pressure for a compression ignition engine with cotton seed oil
as an alternate fuel, International Journal of Engineering, Science and
Technology, Vol. 2, No. 6, 2010, pp. 142-149.
[45] Carlos EF, Talavera-Prieto MC, Fonseca IMA, Portugal ATG, Ferreira
AGM. Measurements of pVT, viscosity, and surface tension of
trihexyltetradecylphosphonium tris(pentafluoroethyl)trifluorophosphate
ionic liquid and modelling with equations of state. J. Chem. Thermodyn
2012; 47: 183–196.
[46] Fluid properties for water, June 2014,
<http://webbook.nist.gov/chemistry/fluid/>.
[47] Private communication from Anton Parr, 2005.
[48] Sun TF, Ten Seldam CA, Kortbeek PJ, Trappeniers NJ, Biswas SN.
Acoustic and thermodynamic properties of ethanol from 273.15 to
333.15 K and up to 280 MPa. Phys Chem Liq 1988;18:107–16.
[49] Ramos MJ, Fernández CM, Casas A, Rodríguez L, Pérez A. Influence of
fatty acid composition of raw materials on biodiesel properties.
Bioresource Technol 2008;100:261–68.
[50] Mohibbe A, Amtul W, Nahar NM. Prospect and Potential of Fatty Acid
Methyl Esters of some Non-traditional Seeds Oils for use as Biodiesel in
India. Biomass Bioener 2005;29:293-302.
[51] Islam MA, Magnusson M, Brown RJ, Ayoko GA, Nabi N, Heimann K.
Microalgal Species Selection for Biodiesel Production Based on Fuel
Properties Derived from Fatty Acid Profiles. Energies 2013;6(11):5676-
702.
[52] ”EN 14214, Fatty acid methyl esters (FAME) for diesel engines,
Requirements and test methods.” European Committee for
Standardization: Management Centre, rue de Stassart 36, B-1050,
Brussels, 2003.
[53] Elbro HS, Fredenslund A, Rasmussen P. Group contribution method for
the prediction of liquid densities as a function of temperature for
solvents, oligomers, and polymers. Ind. Eng. Chem. Res. 1991;30:2576-
82.
[54] Ihmels EC, Gmehling J. Extension and Revision of the Group
Contribution Method GCVOL for the Prediction of Pure Compound
Liquid Densities. Ind. Eng. Chem. Res. 2003;42:408-12.
[55] Pratas MJ, Freitas S, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Densities and Viscosities of Fatty Acid Methyl and Ethyl Esters. J.
Chem. Eng. Data 2010; 55:3983-90.
[56] Pratas MJ, Freitas S, Oliveira MB, Monteiro SC, Lima AS, Coutinho
JAP. Densities and Viscosities of Minority Fatty Acid Methyl and Ethyl
Esters Present in Biodiesel. J. Chem. Eng. Data 2011; 56: 2175–80.
[57] Ndiaye HI, Habrioux M, Coutinho JAP, Paredes MLL, Daridon JL.
Speed of sound, density, and derivative properties of ethyl myristate,
methyl myristate, and methyl palmitate under high pressure, J. Chem.
Eng. Data 2013; 58:1371-1377.
[58] Outcalt SL. Compressed-liquid density measurements of methyl oleate
and methyl linoleate, J. Chem. Eng. Data 2011; 56:4239-4243.
@article{"International Journal of Chemical, Materials and Biomolecular Sciences:68553", author = "Nieves M. C. Talavera-Prieto and Abel G. M. Ferreira and António T. G. Portugal and Rui J. Moreira and Jaime B. Santos", title = "Correlation and Prediction of Biodiesel Density", abstract = "The knowledge of biodiesel density over large ranges
of temperature and pressure is important for predicting the behavior
of fuel injection and combustion systems in diesel engines, and for
the optimization of such systems. In this study, cottonseed oil was
transesterified into biodiesel and its density was measured at
temperatures between 288 K and 358 K and pressures between 0.1
MPa and 30 MPa, with expanded uncertainty estimated as ±1.6 kg⋅m-
3. Experimental pressure-volume-temperature (pVT) cottonseed data
was used along with literature data relative to other 18 biodiesels, in
order to build a database used to test the correlation of density with
temperarure and pressure using the Goharshadi–Morsali–Abbaspour
equation of state (GMA EoS). To our knowledge, this is the first that
density measurements are presented for cottonseed biodiesel under
such high pressures, and the GMA EoS used to model biodiesel
density. The new tested EoS allowed correlations within 0.2 kg·m-3
corresponding to average relative deviations within 0.02%. The built
database was used to develop and test a new full predictive model
derived from the observed linear relation between density and degree
of unsaturation (DU), which depended from biodiesel FAMEs
profile. The average density deviation of this method was only about
3 kg.m-3 within the temperature and pressure limits of application.
These results represent appreciable improvements in the context of
density prediction at high pressure when compared with other
equations of state.
", keywords = "Biodiesel, Correlation, Density, Equation of state,
Prediction.", volume = "8", number = "12", pages = "1377-10", }
