Excess Molar Volumes and Viscosities of Binary Mixture of Diethyl Carbonate+Ethanol at Different Tem

Transactions of Tianjin UniversityIsSN1006-4982ppl01-105Vol 11 No. 2A2005Excess molar Volumes and viscosities of binary mixture ofDiethyl Carbonate Ethanol at Different TemperaturesMA Peisheng马沛生), LI Nannar(李楠楠Key Laboratory for Green Chemical Technology of Education Ministry of ChinaSchool of Chemical Engineering and Technology, Tianjin University Tianjin 300072, ChinaAbstract The purpose of this work was to report excess molar volumes and dynamic viscosities ofthe binary mixture of diethyl carbonate( DEC )+ethanol. Densities and viscosities of the binary mixture of DEC +ethanol at temperatures 293. 15 K-343. 15 K and atmosphericressure were deter-mined over the entire composition range. Densities of the binary mixture of DEC +ethanol weremeasured by using a vibrating U-shaped sample tube densimeter. Viscosities were determined byIsing Ubbelohde suspended-level viscometer. Densities are accurate to 1. 0 x 10-g. cm-3,andviscosities are reproducible within 0. 003 mPa.s. From these data, excess molar volumes anddeviations in viscosity were calculated. Positive excess molar volumes and negative deviations inviscosity for DEC +ethanol system are due to the strong specific interactions. All excess molar voumes and deviations in viscosity fit to the Redlich-Kister polynomial equation. The fitting parameterswere presented and the average deviations and standard deviations were also calculated. The er-rors of correlation are very small. It proves that it is valuable for estimating densities and viscositiesof the binary mixture by the correlated equationKeywords density viscosity excess molar volume diethyl carbonate ethanolDensities and viscosities of liquid mixtures are ture of diethyl carbonate( dEC )+ ethanol. This sys-important both in practice and theory. In practice, tem was chosen because the diethyl carbonate is andensities are necessary in a lot of chemical engineer- important solvent which has been used in a variety ofng calculations( i.e. dimension of storage deposits liquid extraction processes especially in the synthesisdesign of condensers and boilers, etc. )and alsedetermining the dynamic viscosity. The latter is re-of pharmaceuticals and agricultural chemicals. Thiquired in the resolution of many engineering problems compound is also a good gasoline additive in place ofinvolving heat transfer, mass transfer and fluid flow. methyl tert-butyl ether( mTBe to prevent the crackIn theory density, excess volume and viscosity can of abnormal burning and promote the blending octaneused to study the interactions present in mixtures, values 21. A particularly promising method of produsuch as dispersion forces hydrogen bonding interac- cing DEC on an industrial scale is the oxidative cartions, etc. Furthermore, different approaches have bonylation of ethanol over supported copper-based catbeen suggested for predicting mixtures viscosities[ I]contribution models seem to alysts[ 3] Thus it is very important to study the excessmolar volumes and dynanbe particularly promising. Their developments requithe availability of an adequate databasemixture of dec +ethanol in practiceThe purpose of this work was to report excess mo-spite of the importance in industry the ther-ar volumes and dynamic viscosities of the binary mix- modynal中国煤化工 rties for this kind ofCNMHG* Accepted date 2004-08-10MA Peisheng born in 1935 male M ProfE-mailamapeisheng@tju.edu.cnk Supported by Key Laboratory for Green Chemical Technology and New Reactor in Hubei Province( No 2003 BBO1Transactions of Tianjin University Vol 11 No. 2 2005system are scarce in the literatures and there are some tions, molecular weights, and densities of pure comincoherencies between the published data. This work ponents I and 2 respectively and pr is theis a contribution aimed at enlarging the existing data- of the binary mixture. n is the dynamic viscosity ofbase on these properties needed to optimize the struc- the mixture, mi n2 are the viscosities of pure compotural and interaction parameters of group-contribution nents 1 and 2 respects an with mole fraction ofmodThe variation of vE an?s In this paper the densities and viscosities of the dec (x)for the binary system at 293. 15--343.15binary mixture of diethyl DEC ethanol are measured K are represented in Fig. I and Fig.2, respectivelyin the temperature interval of 293. 15 K to 343. 15 Kt atmospheric pressure. At the same time,excessTab. 1 Physical properties of the pure liquids atmolar volumes and deviations of viscosities are calcuT=298. 15 K and atmospheric pressure1 Experimental sectiontaI Literatures Experimental Literatures1.1 MaterialsDEC0.9692800.746Diethyl carbonate(99%) was obtained from theFirst Chemical Agent Factory of Shanghai and etha0.969361nol(99. 5%)was supplied by the First Chemical AEthanol0.785450.7853047]1.0851.0877gent Factory of Tianjin. The products were subjectedto no further purification except drying with molecularFrom Tab. 2 it is clear that the densities for thesieves Type 4A1.2 Apparatus and procedurebinary mixtures increase with the enhancement of themole fraction of dec. it is not difficult to understandThe densities were measured by using a vibrating that the density of dec is higher than that of ethanolU-shaped sample tube densimeter with accuracy ofso with the increase of mole fraction of dec, the den1.0x10-5g cm-3. The viscosities of both the pure sities for the binary system go up steadly. While thecomponents and their mixtures were measured atat- dynamic viscosities n of the binary mixtures take onmospheric pressure and at 298. 15 K by an Ubbelohdecomplicated trend. From x=0-0.609 7 the dynamicsuspended-level viscometer, which was calibratedviscosities n fall steadly and then go up slowly. Thiswith distilled water. And the viscosities are relductphenomenon is not abnormal. Because the change ofble within +0.003 mPa. s. In order to keep a con- the dynamic viscosities for binary mixtures along withstant temperature, the measuring prism was watercomponents is rather complicated. There is not a fixedacketed using a temperature controller with a stability rule. There is probably the intricate dipole-dipole in-of±0.01Kteractions in both components2 Results and discussionRef. [8 suggested that V should be the resultnt contribution fiTab. I gives the experimental densities p, viscos-may be divided arbitrarily into three types, namelyities n for the pure diethyl carbonate and ethanol to- chemical, physical and structural. Physical contri-gether with some values given in the literatures. Tab2 lists experimental values of p and n of the binarybutions that is nonspecific interactions between themixture of DEC ethanol at 293. 15--343. 15 K. real species, present a positive term to VE.TheThe values of p have been used to calculate the excess chemical or specific intermolecular interactions resultmolar volumes vE. The excess molar volumes and dein a volume decrease and these include charge-tralviation of viscosity are computed by中国煤化工 plex-forming interactionsxIM, team a xoMCNMHGgative values(1) The strpIarise from several effects, especially from intersti△m=m-(x1m1+x22(2)tial accommodation and changes of free volume. Inwhere x1, xM1,M2,p1,P2are the mole frac- other words, due to the differences in the free volume102MA Peisheng et al Excess Molar Volumes and Viscosities of Binary Mixture of Diethyl Carbonate+ Ethanoland molar volume between components, structural volumes indicate a predominance of the expansivecontributions arising from geometrical fitting intersti- effects, which is associated with the rupture of the ho-tial accommodated ) of one component into the other momolecular interactions( hydrogen bonds in ethanolslead to negative contribution to VE. From Fig. I we and dipole-dipole interactions in both componentscan see that the excess molar volumes for DEC rather than volume contracting due to the promotion ofethanol system show positive deviation over the whole new hetermolecular interactions of the same kind andcomposition range and at temperatures 293. 15- the molecular packing. These also suggest weak heter-343.15 K. The positive values of the excess molar molecular interactionsTab 2 Densities p dynamic viscosities n excess molar volumes v and viscosity deviations Anfor the binary mixtures at several temperaturesT/)(mPa:s)(cm. mol-)(mPa s(g cm-3)(mPa' s)(cm. mol-I)(0.00000.789741.19390.00000.00000.36850.890480.81510.23080.04160.804961.10860.0073-0.06860.47670.910000.79080.087-0.2118293.150.08900.8208402820.01060.13000.60970.930300.75200.10540.14360.837330.96000.01940.17630.77810.951650.74960.13200.854260.89460.0370-0.21641.00000.974940.79250.00000.000028060.872100.84590.23530.0000451.08510.00000.36850.885270.75340.08600.04160.800510.0l1405900.47670.904650.72310.1056-0.19720.08900.816230.93810.0184-0.11620.60970.924830.6985-0.17580.143604300.77810.946070.7040.20640.8493782540.04880.18831,00000.969280.73940.00000.00000.28060.867050.78360.06180.20450.00000.781140.98780.00000.00000.36850.8800.1058-0.18740.04160.796060.92240.0143-0.05300.47670.899300.66500.1260.181003.0.08900.811610.85320.02650.10810.60970.919330.64950.1452-0.15700.14360.827810.82070.12440.77810.940490.65240.13390.20640.844775410.0619-0.17231.00000.963670.69050.00000.28060.861980.71670.07960.18760.00000.772390.82530.00000.36850.869460.59940.1510.14540.04160.787000.76610.02280.05010.47670.888410.58010.1764-0.14l10.08900.802240.71850.0430-0.08730.60970.908200.56600.19270.1262313.150.1436818100.67720.0674-0.11680.77810.929170.57240.1710-0.08300.20640.834470.64320.09470.13701.00000.952310.60690.00000.28060.851670.61190.11960.15200.00000.763520.69400.00000.00000.36850.858710.51670.20440.12090.04160.777810.64830.03270.03930.47670.877380.50340.2341-0.11760.08900.792690.610.0659-0.06760.60970.896930.4970.24950.1033323.150.14360.808250.57740.09820.09460.77810.917760.50700.21230.06790.20640.824320.55080.13330.11 600000.940890.54100.00000.00000.1665-0.12100.00000.754390.58880.00000.00000.36850.84770.44980.26570.04160.768350.54970.0460.03460.47670.866120.44160.2997-0.096133350.08900.782910.52360.08880.05560.60970.885470.44100.31190.08230.14360.798150.49620.1321-0.07720.77810.906170.45060.25960.05470.20640.813900.47630.17820.09041.00000.929340.48150.00000.00000.28060.830500.46140.21950.09730.00000.745040.50500.00000.00000.04160.758690.47640.05650.0256000LII中国煤化工0.3360.0816CNMHG0.37250.07730.08900.772940.45230.1126-0.04630.38180.067343.150.14360.787860.43090.1686-0.06390.77810.894530.40470.3083-0.04470.20640.803320.4230.22510.06671.00000.917760.43350.00000.00000.28060.819600.40440.2797103一Transactions of Tianjin University Vol 11 No. 2 2005323.15Kwhere dispersion forces are predominant and the mix035:=85Ktures with strong interactions between unlike mole-343.15K30·313,15cules present positive dynamic viscosity deviationFrom Fig. 2 we can see that the deviations in viscosityvalues for DEC ethanol system are negative overthe entire range of composition and at temperatures00f293. 15--343. 15 K. This means that the predominant06effects are the rupture of the dipole-dipole interactionsand the prevalence of the dispersive energy whereasFig 1 V x of diethyl carbonate ethanolere are not strong interactions betweeat different temperaturesand alkane moleculesThe results of excess molar volume and deviationof viscosity fit Redlich-Kister equation to estimate thebinary fitting parameters respectivelyG-0.0V=x1x2∑A(x1-x2)y(3)32:-314△n=x1x2B(x1-x23315K343.15where x, and x2 are the mole fractions of components 1ely. The coefficients Aobtainedby fitting Eqs.(3)and(4)to experimental resultsFig 2 An-x of diethyl carbonate ethanolusing least-square regression method. In each caseat different temperaturesthe optimum number of coefficients is ascertained fromthe examination of the variation in standard deviationSimilar to thee excessSD). And we also calculated the average deviationthelated to the molecul(are)by Eq (6)between the components of the mixtures. So, the dySD=[XV-Vn)(n-1)](5)namic viscosity deviations are function of the molecu-∑(lar interactions as well as the size and shape of theARE(6)moleculesRef [9] stated that a negative dynamicFrom Tab. 3clear that the redlich-Kisterviscosity deviation is a characteristic of the systems equation is suitable to correlate the results of VE andTab 3 Coefficients of Eqs. (3), (4) and standard deviation and average deviation of the binary systenCoefficients A, B, of Egs. (3)and (4)293.15-0,43360.0075-1.03521.02520.52560.14530.18780.3770-0.3825-0.43650.0070,0114298,150.93200.51820,59060.36230.43030.43640.00840.0128303.15A0.85220.48700.11850.15440.78080.0105313.15A0.7060.83960.40110.5920.09970.6634323.15中国煤化工330.57340.74170.34080.10700.213YHCNMHG0.027333.150.46380.65850.27150.51260.06661.61770.14590.02080.032443.150.37140.57060.22430.0716104MA Peisheng et al Excess Molar Volumes and Viscosities of Binary Mixture of Diethyl Carbonate EthanolAn. The fitting errors are very small. It proves that it P-Density ,gis valuable for extrapolating and innerpolating in engiSD-Standard deviationneering design by the correlated equation. At the Referencessame time the purpose of the correlations, developedin the present study is to provide a tool for chemical 1 Moreira A F Garia J Comunas L M J P et al. Experi-engineers in the design and simulation of industrialmental densities and dynamic viscosities of organiccarbonate n-alkane or p-xylene systems at 298. 15 Ksses and installations[J]. Fluid Phase Equilibria 2003 204 233--243quilibria are involved. In addition the correlated [2 Lien P J Lin H M Lee M j et al. Excess molar en-method in this paper can offer a rather accurate meththalpies of diethyl carbonate with m-xylene p-xylened for the correlation of experimental data in similarethylbenzene or ethylbenzoate at 298. 15 K J ]. Fluidsystems for the futurePhase Equilibria 2003 206105--115[3] Roh N S Dunn B C Eyring E M et al. Production of3 Conclusionsdiethyl carbonate from ethanol and carbon monoxideIn this paper, the densities and viscosities of theover a heterogeneous catalytic flow reactor[ J ] FuelProcessing Technology 2003 $3 27-38binary system of DEC ethanol at temperatures [4] Romolo F Comelli F, Ottani S. Excess molar enthal-293. 15--343 15 K and atmospheric pressure are of-fered. The excess molar volumes ve of dEC ethamixtures containing dimethyl carbonate or diethyl carnol system are positive. As expected a predominancebonate +2, 2, 4-trimethylpentane at 288. 15 andof the expansive effects is associated with the rupture313. 15 K , and at atmospheric pressure: Applicationof the homomolecular interactions( hydrogen bonds inof an extended cell model[ J ] Thermochimica Actaethanols and dipole-dipole interactions in both compo1996277:121—132nents )rather than volume contracting. It also indi- [5] Riddik J A, Bungar W B Sakano T K Organic Sol-vents[ M ]. Vol 2. 4th ed. New York: Wiley-Intercates the weak hetermolecular interactions. Condscience 1972ing the dynamic viscosity deviations we have fo[6] Rodriguez A Canosa J Tojo J. Density refractive inthat they are negative for DEC ethanol systemdex on mixing and speed of sound of the ternary mix-This means that the predominant effects are the rup-tures( dimethyl carbonate or diethyl carbonate+ture of the dipole-dipole interactions and the prevamethanol +toluene and the corresponding binarieslence of the dispersive enerat T= 298.15 K[ J].J Chem Thermochimics 2001The excess molar volumes and the dynamic vis331383-1397cosity deviations fit Redlich-Kister equation respec- [7] Tu C H, Ku H C,Wang W Fet al. Volumetric andtively. The fitting parameters are presented. The er-viscometric properties of methanol ethanol propan2-ol, and 2-methylpropan-2-ol with a synthetic C+6rors of correlation are very small. This proves that it ismixture from 298. 15 K to 318. 15 K J].J Chem Engvaluable for estimating densities and viscosities of theData2001462)317-321binary mixture by the correlated equation[8] Nikam P s Kharat S J. Excess molar volumes and de-Nomenclatureviations in viscosity of binary mixtures of N N-dime-thylformamide with aniline and benzonitrile atA B--Adjustable parameters of Eqs. (3)and (4)298.15,303.15,308.15and313.15kJ] / ChemEng data2003484)972-976ght[9] Romano E Trenzado J L Gonzalez e et al. Thermo-V--Excess molar volume, cm. molies of four binary dimethylx— Mole fractioncarbonate +1-alcohol systems at 288. 15-313 15 K[J]. Fluid Phase Equilibria 2003 211 219--240△n- Viscosity deviation mPa·s中国煤化工CNMHG105一