Research Article Excess Transport Properties of Binary Mixtures of Quinoline with Xylenes at Different Temperatures

Advances in Physical Chemistry Volume 1, Article ID 3498, 9 pages doi:1.1155/1/3498 Research Article Excess Transport Properties of Binary Mixtures of Quinoline with Xylenes at Different Temperatures Sk. Fakruddin, 1 Ch. Srinivasu, B. R. Venkateswara Rao, 1 and K. Narendra 1 1 Department of Physics, Velagapudi Ramakrishna Siddhartha Engineering College, Andhra Pradesh, Vijayawada 57, India Department of Physics, Andhra Loyola College, Vijayawada 58, India Correspondence should be addressed to K. Narendra, narenk75@gmail.com Received 3 June 1; Accepted 3 September 1 Academic Editor: Leonardo Palmisano Copyright 1 Sk. Fakruddin et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The ultrasonic velocity and density of binary liquid mixtures of quinoline with o-xylene, m-xylene, and p-xylene have been measured over the entire range of composition at T = 33.15, 38.15, 313.15, and 318.15 K. Using these data, various parameters like adiabatic compressibility (β), intermolecular free length (L f ), and acoustic impedance (Z) and some excess parameters like excess adiabatic compressibility (β E ), excess intermolecular free length (L E f ), excess acoustic impedance (Z E ), and excess ultrasonic velocity (u E ) have been calculated for all the three mixtures. The calculated deviations and excess functions have been fitted to Redlich-Kister polynomial equation. The observed deviations have been explained on the basis of the intermolecular interactions present in these mixtures. 1. Introduction In studying the molecular interactions and physicochemical behaviour of binary liquid mixtures [1, ], the knowledge of thermodynamic and acoustical properties is of great importance. The results are frequently used in process design in many chemical and industrial processes. The studies of binary mixtures containing aromatic hydrocarbons are interesting because they find applications in preferential interactions of polymers in mixed solvents and the studies of polymer phase diagrams. Quinoline is widely used in the manufacturing of dyes, pesticides, and solvent for resins and terpenes. Xylenes are used in printing, rubber, and leather industries. Basically, a binary liquid mixture is formed by the replacement of like contacts in pure liquids by unlike contacts in the mixture. The quantitative and qualitative analyses of excess functions provide information about the nature of molecular interactions in the binary mixtures [3 5]. The literature survey reveals that there has been practically no study of the binary mixtures of these systems from the point of view of their ultrasonic behaviour. In an attempt to explain the nature of interactions occurring between quinoline and xylenes, ultrasonic velocity and density of binary liquid mixtures of quinoline + o- xylene/m-xylene/p-xylene have been determined over the entire range of composition at T = 33.15, 38.15, 313.15, and 318.15 K. Using the experimental values of u and ρ, adiabatic compressibility (β), intermolecular free length (L f ), and acoustic impedance (Z) and some excess parameters like excess adiabatic compressibility (β E ), excess intermolecular free length (L f E ), excess acoustic impedance (Z E ), and excess ultrasonic velocity (u E ) have been calculated. The results were fitted to the Redlich-Kister polynomial equation. In the light of excess parameters, the intermolecular interactions have been estimated [8].. Experimental.1. Materials. The mass fraction of the liquids (obtained from Merck) is as follows: o-xylene (.98), m-xylene (.98), p-xylene (.99), and quinoline (.987). All the liquids used were further purified by standard procedure [9]. The purity of the samples was checked by comparing the experimental values of ultrasonic velocity and density with those available in the literature [6, 7] and these values are compiled in Table 1.

Advances in Physical Chemistry Table 1: Comparison of experimental values of ultrasonic velocities (u) and densities (ρ) of pure liquids with the values reported in the literature. Liquid T/K u/(m s 1 ) ρ/(kg m 3 ) Experimental Literature Experimental Literature Quinoline 33.15 1553.68 1547 a 185.45 185.79 a o-xylene 38.15 1338.75 138.3 b 87.7 87.73 b m-xylene 313.15 134.1 13.34 b 855.7 855.47 b p-xylene 318.15 188.43 189.68 b 85.8 85.6 b a Nath [6]. Al-Kandary et al. [7]. Table : Ultrasonic velocities (u) and densities (ρ) for binary mixtures at T = 33.15, 38.15, 313.15, and 318.15 K. T = 33.15 K T = 38.15 K T = 313.15 K T = 318.15 K u /(m s 1 ) ρ /(Kg m 3 ) u /(m s 1 ) ρ /(Kg m 3 ) u /(m s 1 ) ρ /(Kg m 3 ) u /(m s 1 ) ρ /(Kg m 3 ) {Quinoline (1) + o-xylene ()}. 1338.75 87.7 1315. 869.4 197.5 867.7 178.15 865.9.1 1384.84 91.4 1368.1 896.79 1357.89 893.69 1348.4 891.31.39 144.4 9.99 1386.95 919. 1376.84 915.51 1366.1 911.5.351 144.1 94. 148.89 936.59 1399.4 93.6 1387.95 99.86.458 1444.3 961.85 143.84 956.7 14.53 95.5 1411. 948.11.56 1465.6 981.69 1453.95 977.9 1445.79 974.98 1436.16 967.8.658 1484.84 11.73 1475.37 998.64 1469.5 995.8 146.4 99.71.75 154.47 17.16 1496.3 1. 149. 118. 1484.5 113.3.838 153.58 147.9 1517.95 14.71 1513.47 139.33 156.68 136.86.91 1541.1 167.14 1538.4 163.3 1534.95 16.7 158.63 157.61 1. 1553.68 185.45 155.68 18.11 1547.37 178.6 1541.5 174.99 {Quinoline (1) + m-xylene ()}. 134.1 855.7 185.7 848.7 166.3 845.8 144.1 84.5.138 1375.5 887.18 136.89 88.54 1354.74 875.63 1345.6 871.3.67 1398.6 913.84 1384.79 91.65 1373.68 94.5 1361.5 9.75.388 14.5 931.94 147.74 95.5 1395.6 91.6 138.63 918.9.41 144.16 95.56 148.68 945.83 1418.37 94.91 146.89 94.3.514 1461.95 978.74 145.63 974.7 1443.47 969.91 143.84 966.98.699 148.53 998.14 1474.35 996.3 1466.89 99.34 1457.6 989.9.786 15.3 114.85 1495.16 111.43 1488.84 19.59 1479.89 16.3.866 151.4 143.74 1516.79 138.14 1511.3 134.56 153.1 131.79.937 153.89 166.84 159.6 16.1 155.79 159.3 1519.47 156.74 1. 1553.68 185.45 155.68 18.11 1547.37 178.6 1541.5 174.99 {Quinoline (1) + p-xylene ()}. 188.43 85.8 175.79 846. 153.68 843. 134.73 836.9.141 1371.89 885.76 1361.74 878.51 1351.57 874.51 134.1 869..73 1395.1 99.41 1384.63 93.39 1375.5 91.61 136.89 898.74.395 1415.89 99.81 146.57 918.6 14.1 917.4 1389.47 915.55.418 1436. 949.85 148. 94.34 144.1 938.4 141.73 938.7.511 1457.79 976.74 1451.47 971.93 1446.31 969. 1434.68 965.5.617 148.37 997.73 1473.89 995.6 147.73 991. 1463.1 988.58.793 15.15 113.63 1494.5 11.43 1493.68 19.37 1484.73 15.4.871 1518.6 143.3 1514.63 137.13 159.16 133.54 151.5 13.18.94 153.73 166.53 157.1 161.6 15.63 158. 1515.31 156.3 1. 1553.68 185.45 155.68 18.11 1547.37 178.6 1541.5 174.99

Advances in Physical Chemistry 3 Table 3: Coefficients of Redlich-Kister equation (A i ) and standard deviations (σ) for excess adiabatic compressibility (β E ), excess intermolecular free length (L f E ), excess acoustic impedance (Z E ), and excess ultrasonic velocity (u E ) for binary liquid mixtures. Properties T/K A A 1 A σ {Quinoline (1) + o-xylene ()} 33.15 14.75 15.747 19.3987.631 1 11 β E /(m N 1 38.15 8.78 5.655.155.117 ) 313.15 17.639 1.6 7.3.9585 318.15 18.7916 6.911 35.7657 1.19 1 L f E /(m) 1 4 Z E /(Kg m s 1 ) u E /(m s 1 ) 1 11 β E /(m N 1 ) 1 L f E /(m) 1 4 Z E /(Kg m s 1 ) u E /(m s 1 ) 1 11 β E /(m N 1 ) 1 L f E /(m) 33.15 15.4753 18.356 5.169.7669 38.15 17.736.3448 9.354.9519 313.15 18.8797 4.345 34.6635 1.171 318.15 19.8516 3.8846 5.949 1.4765 33.15 3.8618 13.7678 7.69.6353 38.15 3.3493 1.9783 8.476.71 313.15 3.744 14.36 31.678.8641 318.15 1.8696 17.587 4.69.93 33.15 7.489 15.55 169.334 5.76 38.15 8.65 13.8911 19.96 6.944 313.15 89.98 154.6148 64.913 8.814 318.15 1.3393 4.351 38.897 11.48 {Quinoline (1) + m-xylene ()} 33.15 1.958 31.45 6.7769 1.116 38.15 4.3389 36.3768 31.83 1.3641 313.15 6.398 4.3813 39.13 1.717 318.15 3.673 51.5898 9.7464.1494 33.15 4.367 37.6519 3.435 1.3789 38.15 6.8359 43.78 37.133 1.685 313.15 8.8479 49.996 6.935.995 318.15 3.79 6.38 59.45.5997 33.15 1.579 7.656 5.618 1.966 38.15 1.5394 3.9755 6.854 1.338 313.15 1.1966 3.681 33.4784 1.4769 318.15 11.9598 37.1 41.433 1.6993 33.15 17.556 81.968 1.6969 11.561 38.15 134.4 31.488 5.1364 13.3956 313.15 14.3595 363.645 38.7575 16.739 318.15 157.348 7.734 41.145.179 {Quinoline (1) + p-xylene ()} 33.15 4.3371 4.163 34.869 1.4993 38.15 6.1737 4.5118 35.8559 1.719 313.15 3.5317 5.6633.1 1.989 318.15 33.337 58.4176 51.3519.55 33.15 6.875 48.14 1.438 1.844 38.15 8.78 5.655.155.117 313.15 33.845 59.996 8.8655.3611 318.15 36.5393 68.56 59.897.739

4 Advances in Physical Chemistry Table 3: Continued. Properties T/K A A 1 A σ 33.15 1.6611 35.6773 3.3543 1.4669 1 4 Z E /(Kg m s 1 ) 38.15 1.953 36.633 9.71 1.7861 313.15 13.5849 1.1183 31.3799 1.855 318.15 14.117 3.713 39.18 1.814 u E /(m s 1 ) 33.15 143.469 36.548 71.5399 14.6146 38.15 148.7841 368.437 77.8589 15.3763 313.15 179.548 31.394 319.9555 17.7116 318.15 184.1 85.61 383.787 1.1574 β E /1 1 m N 1 1 3 5 7..4.6.8 1 (a) β E /1 1 m N 1 8 1 1..4.6.8 1 (b) β E /1 1 m N 1 8 1 1..4.6.8 1 (c) Figure 1: (a) Plot of excess adiabatic compressibility (β E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with o-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (b) Plot of excess adiabatic compressibility (β E )versusmolefraction ( ) for binary liquid mixtures of quinoline with m-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (c) Plot of excess compressibility (β E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with p-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K... Procedure. Job smethodofcontinuousvariationwas used to prepare the mixtures of required proportions. The prepared mixtures were preserved in well-stoppard conical flasks. After mixing the liquids thoroughly, the flasks were left undisturbed to allow them to attain thermal equilibrium. The ultrasonic velocities were measured by using single crystal ultrasonic pulse echo interferometer (Mittal enterprises, India; Model: F-8X). It consists of a highfrequency generator and a measuring cell. The measurements of ultrasonic velocities were made at a fixed frequency of 3 Mz. The capacity of the measuring cell is 1 ml. The calibration of the equipment was done by measuring the velocity in carbon tetrachloride and benzene. The results are in good agreement with those reported in the literature [1]. The ultrasonic velocity has an accuracy of ±.5 ms 1. The temperature was controlled by circulating water around the liquid cell from thermostatically controlled constant temperature water bath (accuracy ±.1 K).

Advances in Physical Chemistry 5 L f E /1 m 1 3 5 7..4.6.8 1 (a) L f E /1 m 8 1 1..4.6.8 1 (b) L f E /1 m 8 1 1 14..4.6.8 1 (c) Figure : (a) Plot of excess free length (L f E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with o-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (b) Plot of excess free length (L f E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with m-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (c) Plot of excess free length (L f E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with p-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. The densities of pure liquids and liquid mixtures were measured by using a specific gravity bottle with an accuracy of ±.5%. An electronic balance (Shimadzu AUY, Japan), with a precision of ±.1 mg, was used for the mass measurements. Averages of 4-5 measurements were taken for each sample. 3. Theory From the experimental data of ultrasonic velocity and density various thermodynamic parameters are evaluated using standard equations. Adiabatic compressibility: β = 1 ρu, (1) where ρ and u are density and ultrasonic velocity, respectively. Inter molecular free length: L f = K T β 1/, () where K T is the temperature dependent constant [11]. Acoustic impedance: Z = ρu. (3) The strength of interaction between the component molecules of binary mixtures is well reflected in the deviation of the excess functions from ideality [1]. The excess properties such as β E, L f E, Z E,andu E have been calculated using Y E = Y mix [ Y 1 + x Y ], (4) where Y E is β E, L f E, Z E,oru E and x represents mole fraction of the component and subscript 1 and for the components 1 and, respectively.

6 Advances in Physical Chemistry 4 8 3 6 Z E /1 4 Kg m s 1 1 Z E /1 4 Kg m s 1 4..4.6.8 1 1..4.6.8 1 (a) (b) 8 6 Z E /1 4 Kg m s 1 4..4.6.8 1 (c) Figure 3: (a) Plot of excess acoustic impedance (Z E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with o-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (b) Plot of excess acoustic impedance (Z E ) versus mole fraction ( )for binary liquid mixtures of quinoline with m-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (c) Plot of excess acoustic impedance (Z E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with p-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. Theexcessvaluesofaboveparametersforeachmixture have been fitted to Redlich-Kister polynomial equation [13]: Y E = X 1 X n i= A i (X 1 X ) i. (5) of the excess functions. The standard deviation values were obtained from σ ( ( ni=1 Y E) Y E expt Ycal) E = m n 1/, (6) Thevaluesofthecoefficients A i were calculated by a method of least squares along with the standard deviation σ(y E ). The coefficient is adjustable to the parameters for a better fit where m is the number of experimental points, n is the number of parameters, and Y expt and Y cal are the experimental and calculated parameters, respectively.

Advances in Physical Chemistry 7 5 4 8 7 3 6 u E /m s 1 1 u E /m s 1 5 4 3..4.6.8 1 8 1..4.6.8 1 (a) u E /m s 1 (b) 9 8 7 6 5 4 3 1..4 1.6.8 1 (c) Figure 4: (a) Plot of excess ultrasonic velocity (u E )versusmolefraction( ) for binary liquid mixtures of quinoline with o-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (b) Plot of excess ultrasonic velocity (u E ) versus mole fraction ( )for binary liquid mixtures of quinoline with m-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. (c) Plot of excess ultrasonic velocity (u E ) versus mole fraction ( ) for binary liquid mixtures of quinoline with p-xylene at temperatures:, 33.15 K;, 38.15 K;, 313.15 K;, 318.15 K. C 3 C 3 C 3 C 3 3 C C 3 N 6 7 5 8 4 N 1 3 o-xylene m-xylene p-xylene Quinoline Scheme 1 4. Results and Discussion The structures of the components taken up for study are given in Scheme 1. The experimental values of ultrasonic velocity (u) and density (ρ) for the three binary mixtures over the entire composition range and at temperatures T = 33.15, 38.15, 313.15, and 318.15 K are given in Table. The values of the Redlich-Kister polynomial coefficients A i evaluated by the method of least squares along with standard deviation are given in Table 3. Plots of β E, L f E, Z E,andu E against mole fraction of quinoline for all the three mixtures are given in Figures 1 4.

8 Advances in Physical Chemistry The excess transport properties of the mixtures are influenced by three main types of contributions, namely, (i) due to non specific Van der Waals type forces, (ii) due to hydrogen bonding, dipole-dipole, and donor-acceptor interaction between unlike molecules, and (iii) due to the fitting of smaller molecules into the voids created by the bigger molecules. The first effect leads to contraction in volume hence leads to negative contribution towards u E and positive contribution towards β E. owever, the second effect leads to negative contribution towards β E and positive contribution towards u E. For all the three mixtures, the results of the excess adiabatic compressibility β E plotted in Figures 1(a) 1(c) are negative at all the temperatures studied. The negative values of β E suggest that the mixtures are less compressible than the corresponding ideal mixture. According to Fort and Moore [14], the liquids of different molecular size usually mix with decrease in volume yielding negative β E values. The strength of the interactions between component molecules increases when excess values tend to become increasingly negative. As the temperature increases, the β E values also increase in all the three systems, suggesting that the thermal energy activates the molecules towards complex formation between unlike molecules [15]. It is also observed that the molecular interactions are stronger in quinoline + o-xylene mixture. From Figures (a) (c) it is observed that L E f values are negative for the entire mole fraction range, for all the E four temperatures in case of all the three mixtures. The L f values are increasingly negative as the strength of interaction between component molecules increases [16]. The excess values of Z E which are plotted in Figures 3(a) 3(c) are all positive in all the three liquid systems over the entire composition range and for all the four temperatures studied. The positive excess values of Z E clearly suggest that there exist strong molecular interactions between the molecules of all the three mixtures [17]. The results for the excess ultrasonic velocity u E plotted in Figures 4(a) 4(c) are positive for all the three mixtures at all the temperatures studied. The positive values of u E increase with the increase in temperature which indicates the increase in strength of interaction with temperature in all the three mixtures. The higher positive values of u E are observed in case of quinoline + o-xylene mixture, because the O group attached to the benzene ring in case of o-xylene is stabilized to a great extent through resonance as compared to other mixtures [18]. 5. Conclusions From the data of ultrasonic velocity and density, some thermoacoustical parameters and their excess parameters for the three binary liquid mixtures of quinoline with o-xylene, m-xylene, and p-xylene at T = 33.15, 38.15, 313.15, and 318.15 K are calculated for the entire composition range. From the results of these excess parameters, it is observed that there exists a strong molecular interaction between the unlike molecules in all the three mixtures. The interaction is stronger in case of quinoline + o-xylene mixture as compared to quinoline + m-xylene/p-xylene mixtures. These data will be useful in pharma and perfume industries for handling and mixing processes. References [1] K. Narendra, Ch. Srinivasu, Sk. Fakruddin, and P. N. Murthy, Excess parameters of binary mixtures of anisaldehyde with o- cresol, m-cresol and p-cresol at T = (33.15, 38.15, 313.15, and 318.15) K, The Chemical Thermodynamics, vol. 43, no. 11, pp. 164 1611, 11. [] A. Ali, A. Yasmin, and A. K. Nain, Study of intermolecular interactions in binary liquid mixtures through ultrasonic speed measurement, Indian Pure and Applied Physics, vol. 4, no. 5, pp. 315 3,. [3] S. I. Oswal and N. B. Patel, Speed of sound, isentropic compressibility, viscosity, and excess volume of binary mixtures.. Alkanenitriles + dimethylformamide, + dimethylacetamide, and + dimethyl sulfoxide, Chemical and Engineering Data, vol. 4, no. 4, pp. 845 849, 1995. [4] R. Mehra and R. Israni, Effect of temperature on excess molar volumes of binary mixtures of hexadecane and butanol, Indian Pure and Applied Physics, vol.38,no.,pp. 81 83,. [5] A. Ali and A. K. Nain, Study of intermolecular interaction in binary mixtures of formamide with -propanol, 1,- propanediol and 1,,3-propanetriol through ultrasonic speed measurements, Indian Pure and Applied Physics, vol. 39, pp. 41 47, 1. [6] J. 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Advances in Physical Chemistry 9 [15] S. N. Gour, J. S. Tomar, and R. P. Varma, Study of molecular interactions in binary mixtures using excess thermodynamic parameters, Indian Pure and Applied Physics, vol. 4, p. 6, 1986. [16] A. Ali and A. K. Nain, Ultrasonic and volumetric study of binary mixtures of benzyl alcohol with amides, Bulletin of the Chemical Society of Japan, vol. 75, pp. 681 687,. [17] S. Thirumaran and D. George, Ultrasonic study of intermolecular association through hydrogen bonding in ternary liquid mixtures, Engineering and Applied Sciences, vol. 4, no. 4, pp. 1 11, 9. [18] K.Tiwari,C.Patra,andV.Chakravortty, Molecularinteractions study on binary liquid mixtures of dimethylsulphoxide with benzene, carbontetrachloride and toluene from the excess properties of ultrasonic velocity, density and viscosity, Acoustics Letters, vol. 19, pp. 53 59, 1995.

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