ULTRASONIC INVESTIGATION IN TERNARY MIXTURES - DIETHYL ETHER (DEE) IN N-BUTANOL AND CARBON TETRACHLORIDE

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1 International Journal of Physics, Vol. 4, No. 2, July-December 2011 pp ULTRASONIC INVSTIGATION IN TRNARY MIXTURS - DITHYL THR (D) IN N-BUTANOL AND CARBON TTRACHLORID T. Karunamoy 1*, S. K. Dash 1, S. K. Nayak 2 & B. B. Swain 3 1 DSM, Regionl Institute of ducation (NCRT), Bhubaneswar , Orissa, India 2 Department of Chemistry, Ravenshaw University, Cuttack , Orissa, India 3 Plot No. 15, Chintamaniswar Area, Bhubaneswar , Orissa, India Abstract: Acoustic parameters such as isentropic compressibility, inter molecular free length, acoustic impedance, free volume, internal pressure, ultrasonic absorption co-efficient and relaxation time were computed with the help of measured values of the ultrasonic velocity (u), density (ρ) and viscosity (η) for ternary mixture of diethyl ether, n-butanol and CCl 4 in five sets of solute molefraction at K. The nature of molecular interaction between the polar-polar, polar-apolar components of the ternary mixture are studied by using parameters such as excess intermolecular free length, excess isentropic compressibility, excess internal pressure, excess free volume, excess viscosity and excess acoustic impedance. The molecular interactions are observed to be dipole-dipole, dipole-induced-dipole and dispersive type in the ternary mixtures containing D. The strength of interaction is found to be higher at ( ) polar stiochimetry. Keywords: D; n-butanol; Carbon tetrachloride; xcess acoustic parameters; Molecular interactions. 1. INTRODUCTION In various industrial processes such as petroleum and petrochemical processing, pharmaceutical production, food and fuel industries, and hydrometallurgy [1], liquid-liquid solvent extraction technology is widely used. It owes a significant amount of its present prominence as a separation technique to its successful application in the field of nuclear technology. The use of actinides and lanthanides in nuclear energy industry and interest in metals such as hafnium free zirconium as a reactor construction material have led to the rapid development of many solvent extraction processes that display selectively, simplicity and speed. Diethyl ether (D) is employed as an extractant for zirconium and hafnium separation and production in reactor technology [2]. Furthermore, ethers are also used as oxygenating agents in gasoline technology. The thermodynamic properties in the binary mixtures of alcohols and ether systems have been extensively studied by several workers * Corresponding author: tanmoykarunamoy869@gmail.com

2 102 International Journal of Physics [3, 4]. Although reports are available on dielectric and ultrasonic studies in binary mixtures involving nuclear extractants such as TBP, IBMK etc; [5,6] it is scarce in ternary mixtures using D. As such attempt has been made to investigate the acoustic behavior of ternary mixture containing polar component D, n-butanol and apolar component CCl THORY The measured values of ultrasonic velocity (u), density (ρ) and viscosity (η) for ternary mixtures containing HAA, n-butanol and CCl 4 at K were summarized in Table 1. The values of u, η and ρ were used for evaluation of the acoustical parameters, such as isentropic compressibility (β s ), inter molecular free length (L f ), acoustic impedance (Z), free volume ( V f ), internal pressure ( π i ), relaxation time ( τ) and ultrasonic absorption co-efficient (α/f 2 ) with the help of its standard relations [7, 8] in the ternary mixtures. The excess parameters viz. excess isentropic compressibility (β s ), excess free length (L f ) excess acoustic impendence (Z ), excess free volume (V f ), excess internal pressure (π i ), and excess viscosity (η ) are also computed by using the relation. A = A expt. (x 1 A 1 + x 2 A 2 ). (1) where A is the respective acoustic parameter, x 1 is the molefraction of the polar solute (HAA + n-butanol), x 2 is the molefraction of the apolar solvent (CCl 4 ). 3. XPRIMNTAL The chemicals such as D, n-butanol and CCl 4 used are of AR grade, purified by standard procedures [9] and redistilled before use. The purity of the sample was checked by comparing the measured value of density and viscosity with those reported in the literature [10]. Density was measured with a pycknometer of 25mL capacity calibrated at K with deionised doubly distilled water. At a fixed temperature, the density was determined with an error of 1 in 10 4.Ultrasonic velocity was measured with a single crystal variable path interferometer (Mittal nterprises, New Delhi Model F-81) operated at 2 MHz with an accuracy of 0.5 ms -1. The viscosity was measured using Ostwald viscometer with an accuracy of ±10-6 Pa s. The temperature of the sample was maintained at K with an accuracy of ±0.1 o C with an electronically controlled thermostatic water bath. The weighing of samples was done by (Shimadzu, Japan BL-2201H) digital top loading balance with a precision of ±0.001x10-3 g. The binary mixture of D+n-butanol was prepared by weight for five sets of compositional stoichiometry (molefraction) such as ( ), ( ), ( ), ( ), and ( ) separately. The ternary mixtures of D, n-butanol and CCl 4 were prepared for the molefraction of polar solute (D+n-butanol) in all the five sets. The binary and ternary mixtures prepared by weight were kept in special air tight bottles. 4. RSULTS AND DISCUSSION Ultrasonic velocity ( u), viscosity ( η) and density ( ρ) of the ternary mixtures of D, n-butanol and CCl 4 in the polar compositional stoichimetry of ( ), ( ), ( ),

3 Ultrasonic Investigation in Ternary Mixtures Diethyl ther (D) in 103 Table 1 Variation of Density ( ), Ultrasonic Velocity (u), Viscosity ( ), Adiabatic Compressibility ( s ), Intermolecular Free Length (L f ), relaxation time ( ), Relaxation Amplitude ( /f 2 ), Free Volume (V f ), Internal Pressure ( i ) and Acoustic Impedance (Z) with Mole Fraction (X 1 ) of Polar Solute (D+ n-butanols) in all Compositions Stoichimetry X 1 ρ u Z 10-6 L f x10 10 i x10-6 V f x10 7 x10 12 α/f (kg m -3 ) (m/s) (Nm -2 s) (kg m 2 s -1 ) (m) (Pa) (m 3 mol -1 ) (s) (s 2 m -1 ) at 0.1 D+0.9 n-butanol polar composition at 0.3 D+0.7 n-butanol polar composition at 0.5 D+0.5 n-butanol polar composition Contd...

4 104 International Journal of Physics at 0.7 D +0.3 n-butanol polar composition at 0.9 D+0.1 n-butanol polar composition ( ) and ( ) with the function of molefraction of polar solute were measured at K. The experimental data were used to calculate Z, L f, V f, V a, π i, τ and α/f 2 in these mixtures. Furthermore, such as η, Z, L f, V f, and π i the excess parameters were computed by using equation (1). Some of the relevant data are presented in Table 1 and displayed graphically in Figure 2-6. Perusal of Table 1 shows that the value of u increases while ρ decreases non-linearly with the increase in molefraction of polar solute i.e D and n-butanol in all the polar compositional stoichiometry of the ternary liquid mixtures containing CCl 4. Furthermore, it is observed that the value of h increases in ( ), ( ) while decreases non-linearly in others three polar compositions with increasing molefraction of polar solute in the ternary liquid mixtures. This behavior is different from the ideal mixture behavior which can be attributed to the molecular interaction [11] in the present investigation. D and n-butanol are strongly associated polar liquids having gas phase dipole moment 1.15D and 1.66 D respectively for which short-range specific interaction between polar molecules leads to preferential dipolar alignment. The D as well as n-butanol molecules, in general, have head-tail structures. The dielectric study involving.

5 Ultrasonic Investigation in Ternary Mixtures Diethyl ther (D) in 105 Figure 1: Head-tail Arrangement in D Leading to -multimerization D and n-butanol reveals that the Kirkwood- Fröhlich linear correlation factor g in these two polar liquids, (g D = 1.55 and g n-butanol =3.26) is greater than one [12]. This indicate that there is re-inforcement of parallel dipolar alignment among the like polar molecules of D and n-butanol probably due to the presence of 3-D network of H-bondings among themselves and also stacked together by head-tail arrangement [13]. Furthermore, there is also long and short range ordering through inter and intramolecular H-bondings between like and unlike molecules due to concentration variation of liquid molecules. Close observation of Table 1 shows that the value of ultrasonic velocity increases with the increase in the value of L f and decreases in the value of Z non-linearly in all the ternary mixtures. The variation of ultrasonic velocity in a solution depends upon the increase or decrease of intermolecular free length after mixing the components. On the basis of a model, for sound propagation proposed by yring and Kincaid [14], ultrasonic velocity decreases, if the intermolecular free length increases and vice-versa. However, this model is not strictly valid in our system where both L f and u values increases non-linearly in all the polar compositional stoichiometry of the ternary mixtures. The variations of L f and Z values in the binary and ternary liquid mixtures depend upon the combined effect of increase or decrease in the value of u and ρ which is evident in the present study. It is apparent from its mathematical equation that the ultrasonic velocity and density increase with the decrease in the value of intermolecular free length and vice-versa. However, a low rate of increase in the value of u and high rate of decrease in the value of r favors the increasing trend of L f and decreasing trend of Z values with the molefraction of the polar solute in all the five ternary mixtures containing D, n-butanol and CCl 4. This indicates the molecular interaction as

6 106 International Journal of Physics well as interstitial accommodation among the polar-polar and polar-apolar components of the D, n-butanol and CCl 4 mixtures. Close observation of Table 1 shows that the values of α/f 2 as well as h increases in ( ),( ),( ),( ) while decreases non-linearly in ( ) stoichimetry for the enter range of solute concentration Furthermore, the value of V f decreases while π i increases nonlinearly in ( ),( ),( ),( ) polar compositional stoichiometry and their trends are opposite in ( ) composition in the ternary mixtures. The origin of increase in the value of V f and decrease in the values of p i in the ( ) polar compositional stoichiometry may be due to long- range ordering in D and n-butanol giving rise to H-bonded structure between terminal alcoholic H-atom of n-butanol and central ethereal O-atom of D. Such a moities may have many cavities of H-bonded cage-like structure of D+n-butanol which can accommodate nearly spherical CCl 4 molecules. This is attributed by the difference in molar volume [(V m ) D =103.89cm 3 mol -1 ), (V m ) n-butanol =92.76cm 3 mol -1 ) and (V m ) CCl4 =96.49 cm 3 mol -1 ] between the components of the mixture. This gives rise to a decrease in packing of molecules resulting in increase the value of u in the mixtures. This process continues till all the voids are filled up by CCl 4 molefraction for which the value of V f increases and π i probably decreases in ( ). The relaxation time ( τ) which is in the order of s probably due to structural relaxation process [15], and in such situation it is expected that molecules get rearranged due to co-operative process. The value of η is negative for the whole range of solute concentration in ( ), ( ),( ) while it is positive in others. From the analysis of Figure 2 the behavior of η in the system viz. ( ) and ( ) suggest the strengthening of molecular interaction between the components of ternary mixtures. According to Fort et al [16], the molecular interactions between the interacting molecules for a system were dispersive provided the values of η are found to be negative, where as the existence of specific interaction leading to the formation of complexes in liquid mixtures tends to make η positive. The magnitude of positive values of η decreases in the order of compositional stoichoimetry of ( )>( ). In the present study the positive contribution of Z values in all the ternary mixtures also shows the existence of specific interaction which is reported through the similar observation by Kannapan et al [17]. This behavior is probably supported to be caused by structure changes occurring due to stronger hydrogen bonding through dipole-dipole, dipole-induced-dipole interaction and is attributed by the positive values of the excess viscosity. From close observation of Figure 4, it is evident that the excess values of L f are negative in all the polar compositional stochimetry in the ternary mixtures containing D. In the present findings the magnitude of negative values of L f decreases in the order for composition of ( )>( )> ( )> )> ) which gives an indication of stronger interaction in the liquid mixtures. According to Ramamoorthy et al [18] negative values of L f indicates that sound waves cover longer distance due to decreases in intermolecular free length, assessing the domain nature of hydrogen bond between unlike molecules. In the present investigation the contribution of negative values of L f in maximum magnitude is ( ) systems shows the existence of specific interaction between the components of the ternary mixtures containing D.

7 Ultrasonic Investigation in Ternary Mixtures Diethyl ther (D) in 107 The V f values Figure 6 are found to be positive in ( ), ( ), ( ), ( ) while negative in ( ) with increase in molefraction of polar solute. Acording to Fort et al [17] notice the negative V f tends to decreases as the strength of the interaction between the unlike molecules increases. The values of V f are the resultant contribution from several Figure 2: Variation of with Molefraction (X 1 ) of D+ n-butanol Figure 3: Variation of Z with Molefraction (X 1 ) of D + n-butanol

8 108 International Journal of Physics opposing effect [19]. These may be divided arbitrarily into three types, namely, chemical, physical and structural contribution. Physical contributions, which are non specific interactions between the real species present in the mixtures, contribute a positive term to V f. The chemical or specific intermolecular interaction and structural (interstial Figure 4: Variation of L f with Molefraction (X 1 ) of D+ n-butanol Figure 5: Variation of i with Molefraction (X 1 ) of D+ n-butanol

9 Ultrasonic Investigation in Ternary Mixtures Diethyl ther (D) in 109 accommodation) contributes negative values of V f. In the present study the positive value of V f in ( ), ( ) and ( ) shows, the existence of dispersive force between the component molecules of the ternary mixtures. Furthermore, negative contribution of V f in ( ) and ( ) are in favour of dipole-dipole, dipole-induced-diople interaction between the component molecules of the ternary mixtures. The magnitudes of V f values are are also decreasing in order ( )> ( ). The variation of the excess internal pressure π i may give information regarding the nature and strength of the force existing between the molecules. The excess internal pressure π i values (Figure 5) is found to be positive in ( ) while negative in ( ), ( ) ( ), with molefraction of polar solute. The negative value of π i indicates that only dispersive and dipolar force is operating with complete absence of specific interactions [20]. In the present case, the observed behavior of π i shows the existence of dispersive force in ( ), ( ), ( ) ( ) in the ternary mixture. The positive trend of π i over the entire range of molefraction of the solute in ( ) polar composition is attributed by the negative values of L f and V f in favour of specific interaction between the components of the ternary mixtures containg D. D is an aprotic liquid while n- butanol is protic. The tendency of aprotic liquid is always in breaking nature when mixed with protic liquid. In D+nbutanol system there is an existence of dipolar interaction between O δ- of D and OH δ+ of n-butanol. It is observed that strength of interaction is specific at ( ) system probably due to the availability of more H δ+ species in comparison to OH species as a result there is possibility of dipole-induced-dipole interaction between H δ+ of D component and Cl δ- of CCl 4. On the otherhand the interaction is weak in ( ) system may be due to the breakage of n-butanol by its aprotic counterpart which disperse the dipolar alignment in the polar solute moites resulting dispersive forces. Figure 6: Variation of V f with Molefraction (X 1 ) of D+ n-butanol

10 110 International Journal of Physics 5. CONCLUSIONS Present investigation reveals that the nature of molecular interaction involving D, n-butanol and CCl 4 may be dipole-dipole, dipole-induced dipole and dispersive type between component molecules. The probability of formation of molecular hosts by D and n-butanol (similar to crown ether) cannot be ignored. The spherical molecules of CCl 4 may act as guest molecules in the higher concentration of diethyl ether and n-butanol i.e. at ( ). This host-guest relationship [21] may be the predominant factor among all other types of molecular interactions. Furthermore, the trend of variation of thermo-acoustic parameters shows that the molecular interaction is distinct and its degree is relatively higher in the polar compositional stoichiometry ( ) as compared to other compositions in the ternary mixtures containing D. As such D may be used as an effective extractant in presence of the modifier n-butanol and diluents CCl 4 at ( ) polar composition stoichimetry in the extraction process. Acknowledgement The authors are grateful to Director, Institute of Mathematics, Orissa, for providing infrastructure to complete this reasearch work. The auther wish to thank Deparment of Physics, Regional Institute of ducation (NCRT) Bhubaneswar for carry out the above work. References [1] A. K. Dey, S. M. Khopkar and R. A. Chalmers (1970), Solvent xtraction of Metals, (Van- Nostrand- Reinhold, London). [2] Ritcey. G. M & Ashbrook, A.W (1979), Solvent xtraction Principle and Applications to Process Metallurgy, (lsevier Scientific Publishing Co, Amersterdam). [3] Attri Pankaj, Reddy Madhusudhan P & Ventatesu P. (2010), Indian Journal of Chemistry, 49, 736. [4] Sumathi T. & Maheswari Uma J. (2009), Indian Journal of Pure and Appl. Phys., 47, 782. [5] Dash S. K., Das J. K., Dalai B. and Swain B. B. (2009), Indian J Physics, 16, 195. [6] J. K. Das, S. K. Dash, N. Swain and B. B. Swain (1999), J. Molecular Liquids, 81, 163. [7] M. Dominguez, S. Martin, J. Shantafe, H. Artigas and F. M. Royo (2002), Thermochemica Acta 381, 181. [8] S. K. Mehta, R. K. Chauhan and R. K. Dewan (1996), J. Chem. Soc., Faraday Trans, 92, [9] A. Riddick, W. B. Bunger and T. K. Sakano (1986), Physical Properties and Methods of Purification, Organic Solvents, 4thdn. (Wiley- Inter Science, New York). [10] CRC Handbook of Chemistry and Physics dited by DR. Lide, 87th dn. (CRC Press Boca Raton FL) (2006). [11] Ali Hyder S. & Nain A. K. (2000), Ind J. Phys, 74, 63. [12] Kirkwood J. G. (1939), J. Chem Phys, 7. [13] J. K. Das, S. K. Dash, V. Chakravortty and B. B. Swain (1994), Indian J Chem.Tech., [14] yring H, Kincaid (1938), J. F. Chem. Phys., 6, 620.

11 Ultrasonic Investigation in Ternary Mixtures Diethyl ther (D) in 111 [15] Kinser L.. and Fry A. R. (1989), Fundamentals of Acoustics, New Delhi Wiley astern. [16] R. J. Fort and Moore, W. R. (1966), Trans. Faraday Society, 62, [17] Kannappan V., Jesu Raja Xavier S. & Santhi Jaya R. (2003), Indian J Pure and Appl Phys, 41, 390. [18] Ramamoorthy, K. and Alwan, S. (1978), Current Sci., 47, 334. [19] A. J. Treszc Zanowicz, Kiyohara, O. and Benzon, G. C. (1981), J. Chem Thermodyn., 13, 253. [20] M. Ciler and Kesanovil, D. (1959), Hydrogen Bonding, edited by Hadnzi, D., Pergamon Press (Lond) 1. [21] T. W. Graham Solomons & Craig B. Fryhle (2004), Organic Chemistry. 8 th dn. (John Wiley & Sons (Asia) PT LTD) Singapore.