Dielectric Spectroscopic Study of Molecular Interaction Between Nitriles With Water and Alcohol

Dielectric Spectroscopic Study of Molecular Interaction Between Nitriles With Water and Alcohol

CHAPTER 5 Dielectric Spectroscopic Study of Molecular Interaction Between Nitriles With Water and Alcohol 5.1 INTRODUCTION Nitriles are very polar ...

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CHAPTER 5

Dielectric Spectroscopic Study of Molecular Interaction Between Nitriles With Water and Alcohol 5.1

INTRODUCTION

Nitriles are very polar organic compounds that include the cyanoradical functional group eC^N, i.e., a carbon atom is attached to a nitrogen atom by a triple covalent bond. They can vary in size up to very long molecules most of which consist of carbon atoms attached to each other and also to hydrogen atoms. The nitrogen is very electronegative and the electrons in the triple bond are very easily pulled toward the nitrogen end of the bond. Nitriles have strong permanent dipoleedipole attractions as well as van der Waals dispersion forces between their molecules and are nonhydrogenbonded systems with a large value of dipole moment.1 Many nitriles exist in the liquid state at room temperature.2 The dipoles of molecules of nitriles have a tendency to remain antiparallel in liquid state.1 Nitriles can interact with hydrogen-bonded liquid such as water and alcohol through longrange forces like dipoleedipole interactions.1 Out of nitriles, only acetonitrile is miscible in water.3 Acetonitrile is completely soluble in water and the solubility then falls as chain length increases, i.e., higher nitriles are nonsoluble in water.3 Molecules of nitriles cannot hydrogen bond with themselves but they can hydrogen bond with molecules of hydrogen-bonded liquids such as water and alcohol.4 Higher nitriles are soluble in alcohol. Therefore, alcohols and water can be used as a solvent that are hydrogenbonded liquids. Slightly positive hydrogen atoms in molecules of hydrogen-bonded liquids such as water and alcohol are attracted to the lone pair on the nitrogen atom in a nitrile and a hydrogen bond is formed. Association of nitriles and polar molecules can be of two types. Where a good proton donor is present, the interaction can be of hydrogen bonding. When the proton donor is weak or absent, the interaction involves electrostatic dipoleedipole interactions or actual chemical bond formation, involving the lone pair on the nitrogen atom of a nitrile group. Dielectric relaxation and intermolecular association of pure liquid nitriles and their mixtures have been investigated long back.5e7 Dielectric relaxation in 215 Binary Polar Liquids. http://dx.doi.org/10.1016/B978-0-12-813253-1.00005-7 Copyright © 2017 Elsevier Inc. All rights reserved.

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binary mixtures of acetonitrile/propionitrile and benzene/carbon tetrachloride has been studied by Eloranta and Kadaba.8 Kalaivani et al. have studied dielectric relaxation of nitriles solubilized by sodium dodecyl sulfate in aqueous solutions.9 Madan has studied dielectric relaxation in nitromethane, nitriles, and their mixtures in dilute solutions.10 13C nuclear magnetic resonance and dielectric relaxation in methanolenitrile system have been studied by Madhurima et al.11 Densities, viscosities, refractive indices, and dielectric constants of propylene carbonateeacetonitrile binary system have been reported by Moumouzlas et al.12 Shere et al. have studied dielectric relaxation in butanenitrilee1,2-dichloroethane binary system at 15 C at microwave frequency.13 Hosamani et al. have studied temperature- and frequencydependent dielectric relaxation in p-fluorophenylacetonitrileemethanol system.14 Gagliardi et al. have reported static dielectric constant of acetonitrilee water mixtures at different temperatures. 15 Ternary systems of nitriles and alcohols in benzene at microwave frequency have been studied by Subramanian et al. 16 In this chapter, information about interaction of nonhydrogen-bonded liquids nitriles with hydrogen-bonded liquids water and alcohols through dielectric relaxation parameters obtained at microwave frequencies is given. Dielectric relaxation parameters for the following systems using time domain reflectometry technique in microwave frequency range have been presented (Tables 5.1): 1. 2. 3. 4. 5. 6. 7. 8.

Pure nitriles2 Tables 5.2 and 5.3; Acetonitrileewater1 Tables 5.4e5.7; Figs. 5.1e5.5 Acetonitrileemethanol3,4 Tables 5.8e5.11; Figs. 5.6e5.10 Butanenitrileemethanol3,4 Tables 5.12e5.15; Figs. 5.11e5.15 Pentanenitrileemethanol3,4 Tables 5.16e5.19; Figs. 5.16e5.20 Hexanenitrileemethanol3,4 Tables 5.20e5.23; Figs. 5.21e5.25 Octanenitrileemethanol3,4 Tables 5.24e5.27; Figs. 5.26e5.30 p-Fluorophenylacetonitrileemethanol14 Tables 5.28e5.31; Figs. 5.31e5.35

5.2 Pure Nitriles

Table 5.1 Pure Liquids ε0

Liquid Acetonitrile Butanenitrile Pentanenitrile Hexanenitrile Octanenitrile p-Fluorophenyle acetonitrile Water Methanol

5.2

Time Domain Reflectometry Technique

Other Technique17

Density17, gm/cm3

Mol. Wt.17

Dipole Moment,17 m Debye

36.90 22.00 21.00 16.30 13.00 15.64

36.64 24.83 20.04 17.26 13.90 e

0.786 0.794 0.795 0.809 0.814 1.126

41.05 69.11 83.13 97.16 125.21 135.14

3.92 3.89 4.12 3.48 e 4.85

78.5 33.7

80.10 33.00

1.00 0.789

18.01 32.04

1.85 1.70

PURE NITRILES Table 5.2 Static Permittivity εo for Pure n-Nitriles ε0 Nitrile

0 C

10 C

25 C

35 C

45 C

Acetonitrile Butanenitrile Pentanenitrile Hexanenitrile Octanenitrile

40.0 26.2 23.0 18.1 14.7

38.2 24.3 21.5 18.0 13.2

36.9 22.0 21.0 16.3 13.0

36.1 21.1 19.1 16.0 12.2

33.7 20.3 11.3 14.2 10.8

Table 5.3 Relaxation Time s for Pure n-Nitriles s (ps) Nitrile

0 C

10 C

25 C

35 C

45 C

Acetonitrile Butanenitrile Pentanenitrile Hexanenitrile Octanenitrile

6.4 10.2 16.8 28.2 45.0

3.6 9.9 14.4 22.0 36.6

3.4 8.9 13.0 17.4 31.4

2.7 8.0 11.3 16.3 25.6

1.3 6.7 10.9 14.2 22.0

217

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5.3

ACETONITRILEeWATER BINARY SYSTEM

Table 5.4 Dielectric Relaxation Parameters for Acetonitrile (ACN)e Water Binary System Vol. Fraction ACN in Water

ε0

s (ps)

ε0

0 C 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

87.9 83.1 83.2 74.6 74.7 71.0 64.7 56.8 53.1 44.6 42.8

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

78.5 76.8 74.9 69.7 66.8 54.5 52.3 52.0 47.3 41.4 37.0

17.6 17.8 18.8 18.7 19.6 18.1 15.9 14.3 12.7 9.5 8.8 25 C 8.8 10.9 10.6 11.2 10.8 11.2 10.6 9.6 8.8 5.4 3.4

s (ps) 10 C

83.9 78.9 76.0 74.0 67.7 61.0 58.7 50.4 47.4 40.0 39.2 73.1 73.8 70.4 68.3 65.2 60.7 52.6 50.7 46.0 34.7 33.1

12.7 13.9 13.8 13.9 14.6 13.8 12.9 10.0 9.5 6.0 3.6 40 C 5.8 6.5 6.6 6.7 6.6 6.5 6.1 6.0 5.5 3.2 2.5

5.3 AcetonitrileeWater Binary System

90 0°C 10°C 25°C 40°C

80

ε0

70

60

50

40

30 0.0

0.2

0.4 0.6 Vol. fraction of Acetonitrile

0.8

1.0

FIGURE 5.1 Static permittivity for acetonitrileewater binary system.

20

0°C 10°C 25°C 40°C

18 16

τ (ps)

14 12 10 8 6 4 2 0.0

0.2

0.4 0.6 Vol. fraction of Acetonitrile

FIGURE 5.2 Relaxation time for acetonitrileewater binary system.

0.8

1.0

219

Dielectric Spectroscopic Study of Molecular Interaction

2 0 -2

εΕ

-4 -6 -8 -10

0°C 10°C 25°C 40°C

-12 0.0

0.2

0.4 0.6 Mole fraction of Acetonitrile

0.8

1.0

FIGURE 5.3 Excess permittivity for acetonitrileewater binary system.

0 -20 -40 -1

CHAPTER 5:

(1/τ) (1/τ)E (ps )

220

-60 -80

-100

0°C 10°C 25°C 40°C

-120 0.0

0.2

0.4 0.6 Mole fraction of Acetonitrile

FIGURE 5.4 Excess inverse relaxation time 103 for acetonitrileewater binary system.

0.8

1.0

5.3 AcetonitrileeWater Binary System

Table 5.5 Bj Coefficients of RedlicheKister Equation for AcetonitrileeWater Binary System Excess Permittivity Temp.  C 0 10 25 40

B0

B1

38 47 32 18

17 7 68 12

B2

Excess Inv. Relax. Time B0 3 103

B3

12 20 35 47

22 29 187 145

49 322 417 480

B1 3 103

B2 3 103

69 108 176 158

89 17 164 777

Table 5.6 Kirkwood Correlation Factor geff for Acetonitrile (ACN)e Water Binary System geff

Vol. Fraction of ACN in Water

0 C

10 C

25 C

40 C

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

2.64 2.40 2.29 1.97 1.90 1.74 1.53 1.29 1.17 0.94 0.85

2.67 2.40 2.22 2.11 1.86 1.62 1.55 1.33 1.13 0.91 0.87

2.62 2.47 2.31 2.06 1.88 1.76 1.37 1.29 1.10 0.99 0.86

2.48 2.36 2.18 2.04 1.88 1.69 1.47 1.31 1.10 0.87 0.81

Table 5.7 Activation Energy for Acetonitrile (ACN)eWater Binary System Vol. Fraction of ACN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

10.00 14.78 15.45 14.91 16.33 14.82 13.77 11.34 11.08 15.12 17.13

B3 3 103 125 196 768 1332

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1.0 0°C 10°C 25°C 40°C Theo.

0.8

0.6

fB

222

0.4

0.2

0.0 0.0

0.2

0.4 0.6 Vol. fraction of Acetonitrile

0.8

1.0

FIGURE 5.5 Bruggeman factor for acetonitrileewater binary system. The Bruggeman parameter “a” is found to be 1.527, 1.301, 1.459, and 1.922 at 0, 10, 25, and 40 C, respectively, for acetonitrileewater binary system.

5.4

ACETONITRILEeMETHANOL BINARY SYSTEM Table 5.8 Dielectric Relaxation Parameters for Acetonitrile (ACN)e Methanol Binary System Vol. Fraction of ACN

ε0

s (ps)

ε0

0 C 0.0 0.1 0.2 0.5 0.8 0.9 1.0

37.0 36.5 38.5 37.5 37.8 37.5 37.9

0.0 0.1 0.2 0.5 0.8 0.9 1.0

30.0 30.2 30.0 30.4 31.3 29.4 30.4

76.5 58.3 45.2 22.1 12.2 8.9 7.5 35 C 44.5 35.7 28.7 14.9 8.5 5.3 3.4

s (ps)

ε0

10 C 35.0 35.6 35.9 35.6 35.5 35.0 35.2 28.0 29.1 28.0 30.1 30.8 30.1 29.9

64.4 50.5 39.2 19.1 8.9 7.3 6.6 45 C 37.2 30.4 24.9 12.1 6.1 4.3 2.5

s (ps) 25 C

33.7 34.0 34.0 33.9 33.9 34.3 34.3

51.4 42.3 34.1 17.5 7.8 6.4 4.2

5.4 AcetonitrileeMethanol Binary System

42 0°C 10°C 25°C 35°C

40 38

ε0

36 34 32 30 28 0.0

0.2

0.4

0.6

0.8

1.0

Vol. fraction of Acetonitrile

FIGURE 5.6 Static permittivity for acetonitrileemethanol binary system.

80 0°C 10°C 25°C 35°C

70 60

τ (ps)

50 40 30 20 10 0 0.0

0.2

0.4 0.6 Vol. fraction of Acetonitrile

FIGURE 5.7 Relaxation time for acetonitrileemethanol binary system.

0.8

1.0

223

Dielectric Spectroscopic Study of Molecular Interaction

0°C 10°C 25°C 35°C

1.5

1.0

εΕ

0.5

0.0

-0.5

-1.0 0.0

0.2

0.4 0.6 Mole fraction of Acetonitrile

0.8

1.0

FIGURE 5.8 Excess permittivity for acetonitrileemethanol binary system.

0

-20

-40 -1

CHAPTER 5:

(1/ (1/τ) τ)E (ps )

224

-60

-80 0°C 10°C 25°C 35°C

-100

-120 0.0

0.2

0.4 0.6 Mole fraction of Acetonitrile

FIGURE 5.9 Excess inverse relaxation time 103 for acetonitrileemethanol binary system.

0.8

1.0

5.4 AcetonitrileeMethanol Binary System

Table 5.9 Bj Coefficients of RedlicheKister Equation for Acetonitrilee Methanol Binary System Excess Permittivity Temp.  C

B0

B1

B2

B3

0 10 25 35

1 2 1 4

7

3 1 7

8 12 1 48

1 4 21

14

Excess Inv. Relax. Time B0 3 103 100 87 221 359

B1 3 103

B2 3 103

B3 3 103

119 43 38 449

59 98 193 150

234 57 437 290

Table 5.10 Kirkwood Correlation Factor geff for Acetonitrile (ACN)e Methanol Binary System geff Vol. Fraction of ACN

0 C

10 C

25 C

35 C

45 C

0.0 0.1 0.2 0.4 0.5 0.6 0.8 0.9 1.0

3.22 2.57 2.23 1.57 1.38 1.22 1.01 0.92 0.87

3.15 2.67 2.20 1.59 1.41 1.27 1.03 0.93 0.86

3.22 2.65 2.15 1.59 1.39 1.23 1.02 0.94 0.88

2.93 2.58 2.09 1.30 1.38 1.27 1.05 0.94 0.89

2.81 2.53 2.04 1.35 1.37 1.17 1.01 0.92 0.85

Table 5.11 Activation Energy DH for Acetonitrile (ACN)eMethanol Binary Systems Vol. Fraction of ACN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.5 0.8 0.9 1.0

6.3 7.84 6.91 6.48 6.48 8.55 15.51

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1.0

0.8

0.6 fB

226

0.4

0°C 10°C 25°C 35°C Theo.

0.2

0.0 0.0

0.2

0.4 0.6 Vol. fraction of Acetonitrile

0.8

1.0

FIGURE 5.10 Bruggeman factor for acetonitrileemethanol binary system. The Bruggeman parameter “a” is found to be 0.321, 0.513, 0.484, and 1.298 at 0, 10, 25, and 35 C, respectively, for acetonitrileemethanol binary system.

5.5

BUTANENITRILEeMETHANOL BINARY SYSTEM

Table 5.12 Dielectric Relaxation Parameters for Butanenitrile (BN)e Methanol Binary System Vol. Fraction of BN

ε0

0.0 0.1 0.2 0.5 0.8 0.9 1.0

37.0 35.7 33.0 31.5 29.2 27.6 26.2

0.0 0.1 0.2 0.5 0.8 0.9 1.0

30.0 28.4 29.4 27.2 26.0 23.0 21.1

s (ps) 0 C 76.5 68.0 53.8 31.5 16.8 11.2 10.2 35 C 44.5 37.1 35.5 21.3 12.0 9.5 8.0

ε0 35.0 35.1 32.1 30.0 27.3 26.3 24.3 28.0 26.9 27.3 23.5 23.0 22.5 20.3

s (ps) 10 C 64.4 56.8 45.8 23.8 13.9 10.3 9.9 45 C 37.2 35.4 30.3 18.8 11.6 9.1 6.7

ε0 33.7 31.9 31.6 29.2 25.9 25.4 22.0

s (ps) 25 C 51.4 49.2 40.7 23.5 13.4 10.0 8.9

5.5 ButanenitrileeMethanol Binary System

38 0°C 10°C 25°C 35°C

36 34 32

ε0

30 28 26 24 22 20 0.0

0.2

0.4 0.6 Vol. fraction of Butanenitrile

0.8

1.0

FIGURE 5.11 Static permittivity for butanenitrileemethanol binary system.

80 0°C 10°C 25°C 35°C

70 60

τ(ps)

50 40 30 20 10 0.0

0.2

0.4 0.6 Vol. fraction of Butanenitrile

FIGURE 5.12 Relaxation time for butanenitrileemethanol binary system.

0.8

1.0

227

Dielectric Spectroscopic Study of Molecular Interaction

2

0°C 10°C 25°C 35°C

1

εΕ

0

-1

-2

0.0

0.2

0.4 0.6 Mole fraction of Butanenitrile

0.8

1.0

FIGURE 5.13 Excess permittivity for butanenitrileemethanol binary system.

40 0°C 10°C 25°C 35°C

30 20 10

-1

CHAPTER 5:

(1/τ)E (ps )

228

0 -10 -20 -30 -40 0.0

0.2

0.4 0.6 Mole fraction of Butanenitrile

FIGURE 5.14 Excess inverse relaxation time 103 butanenitrileemethanol binary system.

0.8

1.0

5.5 ButanenitrileeMethanol Binary System

Table 5.13 Bj Coefficients of RedlicheKister Equation for Butanenitrilee Methanol Binary System Temp C 0 10 25 35

Excess Permittivity B0 6 1 2 6

B1 7 14 1 11

Excess Inv. Relax. Time

B2

B3

B0 3 103

B1 3 103

B2 3 103

2 11 13 19

29 5 21 20

113 45 34 35

211 59 3 18

89 250 103 41

B3 3 103 287 293 147 35

Table 5.14 Kirkwood Correlation Factor geff for Butanenitrile (BN)e Methanol Binary System geff Vol. Fraction of BN

0 C

10 C

25 C

35 C

45 C

0.0 0.1 0.2 0.5 0.8 0.9 1.0

3.22 2.66 2.08 1.44 1.04 0.91 0.80

3.20 2.71 2.22 1.44 1.00 0.89 0.76

3.11 2.58 2.23 1.47 1.00 0.89 0.73

2.94 2.37 2.14 1.41 1.04 0.85 0.72

2.81 2.31 2.05 1.25 0.94 0.85 0.71

Table 5.15 Activation Energy DH for Butanenitrile (BN)eMethanol Binary Systems Vol. Fraction of BN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.5 0.8 0.9 1.0

6.30 8.38 6.27 4.64 3.11 0.64 4.00

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1.0 0°C 10°C 25°C 35°C Theo.

0.8

0.6 fB

230

0.4

0.2

0.0 0.0

0.2

0.4 0.6 Vol. fraction of Butanenitrile

0.8

1.0

FIGURE 5.15 Bruggeman factor for butanenitrileemethanol binary system. The Bruggeman parameter “a” is found to be 1.127, 1.956, 1.872, and 2.097 at 0, 10, 25, and 35 C, respectively, for butanenitrileemethanol binary system.

5.6

PENTANENITRILEeMETHANOL BINARY SYSTEM

Table 5.16 Dielectric Relaxation Parameters for Pentanenitrile (PN)e Methanol Binary System Vol. Fraction of PN 0.0 0.1 0.2 0.5 0.8 0.9 1.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0

ε0

s (ps)

0 C 37.00 76.5 35.7 71.7 34.8 64.1 30.7 42.6 26.3 24.7 25.7 22.0 23.0 16.8 35 C 30.00 44.5 29.0 40.8 27.9 35.5 24.8 22.6 21.3 14.2 20.2 12.6 19.1 11.3

ε0 35.0 34.0 32.8 29.0 24.7 23.2 21.5 28.0 27.4 26.7 23.7 20.6 19.3 17.9

s (ps) 10 C 64.4 54.1 48.6 33.2 20.8 18.5 14.4 45 C 37.2 35.9 32.3 20.6 12.6 11.7 10.9

ε0 33.7 32.0 31.0 27.6 23.8 22.5 21.0

s (ps) 25 C 51.4 47.3 44.1 29.9 18.2 15.7 13.1

5.6 PentanenitrileeMethanol Binary System

0°C 10°C 25°C 35°C

35

ε0

30

25

20

0.0

0.2

0.4 0.6 Vol. fraction of Pentanenitrile

0.8

1.0

FIGURE 5.16 Static permittivity for pentanenitrileemethanol binary system.

80 0°C 10°C 25°C 35°C

70 60

τ (ps)

50 40 30 20 10 0.0

0.2

0.4 0.6 Vol. fraction of Pentanenitrile

FIGURE 5.17 Relaxation time for pentanenitrileemethanol binary system.

0.8

1.0

231

Dielectric Spectroscopic Study of Molecular Interaction

0.0

-0.5

εΕ

-1.0

-1.5

-2.0 0°C 10°C 25°C 35°C

-2.5

0.0

0.2

0.4

0.6

0.8

1.0

Mole fraction of Pentanenitrile

FIGURE 5.18 Excess permittivity for pentanenitrileemethanol binary system.

8 0°C 10°C 25°C 35°C

6

4 -1

CHAPTER 5:

(1/τ)E (ps ) (1/

232

2

0

-2

-4 0.0

0.2

0.4 0.6 Mole fraction of Pentanenitrile

FIGURE 5.19 Excess inverse relaxation time 103 pentanenitrileemethanol binary system.

0.8

1.0

5.6 PentanenitrileeMethanol Binary System

Table 5.17 Bj Coefficients of RedlicheKister Equation for Pentanenitrilee Methanol Binary System Excess Permittivity Temp.  C 0 10 25 35

B0 11 9 8 9

B1

B2

4 3 3 2

12 0 0 1

Excess Inv. Relax. Time

B3 12 1 1 3

B0 3 103 3 1 1 28

B1 3 103 9 3 19 19

B2 3 103

B3 3 103

53 38 18 26

44 59 34 1

Table 5.18 Kirkwood Correlation Factor geff for Pentanenitrile (PN)e Methanol Binary System geff Vol. Fraction of PN

0 C

10 C

25 C

35 C

45 C

0.0 0.1 0.2 0.5 0.8 0.9 1.0

3.22 2.71 2.35 1.50 0.99 0.86 0.74

3.15 2.67 2.27 1.46 0.96 0.83 0.71

3.12 2.64 2.26 1.46 0.97 0.85 0.73

2.93 2.46 2.09 1.35 0.89 0.78 0.68

2.81 2.40 2.06 1.33 0.89 0.77 0.66

Table 5.19 Activation Energy DH for Pentanenitrile (PN)eMethanol Binary Systems Vol. Fraction of PN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.5 0.8 0.9 1.0

6.30 8.00 8.08 8.99 8.29 7.88 4.51

233

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Dielectric Spectroscopic Study of Molecular Interaction

1.0 0°C 10°C 25°C 35°C Theo.

0.8

0.6 fB

234

0.4

0.2

0.0 0.0

0.2

0.4 0.6 Vol. fraction of Pentanenitrile

0.8

1.0

FIGURE 5.20 Bruggeman factor for pentanenitrileemethanol binary system. The Bruggeman parameter “a” is found to be 1.437, 1.407, 1.368, and 1.221 at 0, 10, 25, and 35 C, respectively, for pentanenitrileemethanol binary system.

5.7

HEXANENITRILEeMETHANOL BINARY SYSTEM

Table 5.20 Dielectric Relaxation Parameters for Hexanenitrile (HN)eMethanol Binary System Vol. Fraction of HN

ε0

0.0 0.1 0.2 0.5 0.8 0.9 1.0

37.0 34.9 32.2 26.6 21.4 19.7 18.1

0.0 0.1 0.2 0.5 0.8 0.9 1.0

30.0 27.4 25.8 21.7 18.0 17.1 16.0

s (ps) 0 C 76.50 73.6 66.8 54.0 35.2 30.8 28.2 35 C 44.50 40.8 35.3 26.6 19.8 17.3 16.3

ε0

s (ps)

28.0 25.4 23.6

10 C 64.4 55.9 50.0 40.4 26.4 23.2 22.0 45 C 37.2 30.8 30.4

15.8 14.9 14.2

17.7 15.7 14.2

35.0 33.2 31.3 25.9 21.0 19.6 18.0

ε0 33.7 31.4 29.3 24.3 19.1 17.6 16.3

s (ps) 25 C 51.4 50.5 46.8 35.2 22.2 19.3 17.4

5.7 HexanenitrileeMethanol Binary System

0°C 10°C 25°C 35°C

35

ε0

30

25

20

15

0.0

0.2

0.4

0.6

0.8

1.0

Vol. fraction of Hexanenitrile

FIGURE 5.21 Static permittivity for hexanenitrileemethanol binary system.

80 0°C 10°C 25°C 35°C

70

τ (ps)

60 50 40 30 20 0.0

0.2

0.4 0.6 Vol. fraction of Hexanenitrile

FIGURE 5.22 Relaxation time for hexanenitrileemethanol binary system.

0.8

1.0

235

Dielectric Spectroscopic Study of Molecular Interaction

0

-1

-2

εΕ

CHAPTER 5:

-3

-4 0°C 10°C 25°C 35°C

-5

-6 0.0

0.2

0.4 0.6 Mole fraction of Hexanenitrile

0.8

1.0

FIGURE 5.23 Excess permittivity for hexanenitrileemethanol binary system.

0°C 10°C 25°C 35°C

6 5 4

(1/τ)E (ps-1) (1/

236

3 2 1 0 0.0

0.2

0.4

0.6

Mole fraction of Hexanenitrile

FIGURE 5.24 Excess inverse relaxation time 103 hexanenitrileemethanol binary system.

0.8

1.0

5.7 HexanenitrileeMethanol Binary System

Table 5.21 Bj Coefficients of RedlicheKister Equation for Hexanenitrilee Methanol Binary System Excess Permittivity Temp.  C 0 10 25 35

B0 21 19 19 17

B1

B2

10 11 7 5

10 4 4 9

Excess Inv. Relax. Time B0 3 103

B3 12 4 7 31

7 16 13 23

B1 3 103 19 33 27 1

B2 3 103 4 7 9 31

B3 3 103 17 59 24 20

Table 5.22 Kirkwood Correlation Factor geff for Hexanenitrile (HN)e Methanol Binary System geff Vol. Fraction of HN

0 C

10 C

25 C

35 C

45 C

0.0 0.1 0.2 0.5 0.8 0.9 1.0

3.22 2.76 2.32 1.50 0.97 0.83 0.72

3.15 2.63 2.33 1.51 0.99 0.86 0.74

3.12 2.70 2.30 1.49 0.94 0.81 0.70

2.98 2.42 2.08 1.37 0.91 0.81 0.71

2.81 2.31 1.96

Table 5.23 Activation Energy DH for Hexanenitrile (HN)e Methanol Binary Systems Vol. Fraction of HN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.5 0.8 0.9 1.0

6.30 10.22 9.45 10.57 8.06 7.95 8.60

0.82 0.72 0.64

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1.0 0°C 10°C 25°C 35°C Theo.

0.8

0.6 fB

238

0.4

0.2

0.0

0.0

0.2

0.4 0.6 Vol. fraction of Hexanenitrile

0.8

1.0

FIGURE 5.25 Bruggeman factor for hexanenitrileemethanol binary system. The Bruggeman parameter “a” is found to be 1.062, 1.118, 1.136 and 0.794 at 0, 10, 25 and 35 C respectively for hexanenitrileemethanol binary system.

5.8

OCTANENITRILEeMETHANOL BINARY SYSTEM

Table 5.24 Dielectric Relaxation Parameters for Octanenitrile (ON)e Methanol Binary System Vol. Fraction of ON

ε0

s (ps)

ε0

0 C 0.0 0.1 0.2 0.5 0.8 0.9 1.0 0.0 0.1 0.2 0.5 0.8 0.9 1.0

37.00 34.8 32.1 24.2 18.6 17.0 14.7

76.50 74.0 70.2 58.0 49.7 47.4 45.0 35 C 30.00 44.50 27.3 43.0 25.8 42.4 19.7 32.4 14.8 29.2 13.2 28.1 12.2 25.6

35.0 31.4 29.0 22.9 16.5 15.2 13.2 28.0 24.8 22.8 17.0 12.6 11.4 10.8

s (ps) 10 C 64.4 59.5 58.5 54.5 40.7 38.6 36.6 45 C 37.2 33.9 32.7 28.4 23.4 22.8 22.0

ε0 33.7 30.9 28.4 21.6 15.7 14.0 13.0

s (ps) 25 C 51.4 52.0 50.0 42.2 35.3 32.4 31.4

5.8 OctanenitrileeMethanol Binary System

0°C 10°C 25°C 35°C

35

ε0

30

25

20

15

0.0

0.2

0.4 0.6 Vol. fraction of Octanenitrile

0.8

1.0

FIGURE 5.26 Static permittivity for octanenitrileemethanol binary system.

80 0°C 10°C 25°C 35°C

70

τ (ps)

60

50

40

30

0.0

0.2

0.4

0.6

Vol. fraction of Octanenitrile

FIGURE 5.27 Relaxation time for octanenitrileemethanol binary system.

0.8

1.0

239

Dielectric Spectroscopic Study of Molecular Interaction

0

-2

εΕ

CHAPTER 5:

-4

-6 0°C 10°C 25°C 35°C

-8

0.0

0.2

0.4

0.6

0.8

1.0

Mole fraction of Octanenitrile

FIGURE 5.28 Excess permittivity for octanenitrileemethanol binary system.

6 0°C 10°C 25°C 35°C

5

4

(1/τ)E (ps-1) (1/

240

3

2

1

0 0.0

0.2

0.4

0.6

Mole fraction of Octanenitrile

FIGURE 5.29 Excess inverse relaxation time 103 octanenitrileemethanol binary system.

0.8

1.0

5.8 OctanenitrileeMethanol Binary System

Table 5.25 Bj Coefficients of RedlicheKister Equation for Octanenitrilee Methanol Binary System Excess Permittivity Temp.  C

B0

0 10 25 35

29 29 29 25

B1 30 3 17 12

B2 19 7 14 12

Excess Inv. Relax. Time

B3

B0 3 103

B1 3 103

B2 3 103

B3 3 103

15 85 4 21

10 11 12 14

10 23 3 46

5 34 13 27

19 77 16 102

Table 5.26 Kirkwood Correlation Factor geff for Octanenitrilee Methanol Binary System geff Vol. Fraction of ON

0 C

10 C

25 C

35 C

45 C

0.0 0.1 0.2 0.5 0.8 0.9 1.0

3.22 2.85 2.47 1.57 1.02 0.88 0.72

3.15 2.66 2.31 1.53 0.93 0.81 0.66

3.12 2.75 2.38 1.52 0.93 0.78 0.68

2.93 2.50 2.23 1.42 0.90 0.75 0.66

2.81 2.34 2.02 1.25 0.78 0.66 0.59

Table 5.27 Activation Energy DH for Octanenitrile (ON)eMethanol Binary Systems Vol. Fraction of ON

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.5 0.8 0.9 1.0

6.30 9.18 8.96 9.69 8.90 8.62 8.67

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1.0 0°C 10°C 25°C 35°C Theo.

0.8

0.6 fB

242

0.4

0.2

0.0

0.0

0.2

0.4 0.6 Vol. fraction of Octanenitrile

0.8

1.0

FIGURE 5.30 Bruggeman factor for octanenitrileemethanol binary system. The Bruggeman parameter “a” is found to be 1.160, 1.081, 1.045, and 1.008 at 0, 10, 25, and 35 C, respectively, for octanenitrilee methanol binary system.

5.9

P-FLUOROPHENYLACETONITRILEeMETHANOL BINARY SYSTEM

Table 5.28 Dielectric Relaxation Parameters for p-Fluorophenylacetonitrile (FPAN)eMethanol Binary System Vol. Fraction of FPAN

ε0

s (ps)

ε0

10 C 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

35.72 33.82 32.05 30.17 28.52 26.84 24.80 21.93 19.60 17.84 16.23

66.01 62.14 56.05 50.82 44.18 33.18 32.25 25.83 22.02 19.51 17.16

s (ps) 20 C

34.28 32.29 30.66 28.92 27.02 25.01 22.89 20.31 17.84 16.61 15.64

55.76 54.13 46.97 40.54 34.45 29.83 25.85 22.65 19.70 17.08 15.01

5.9 p-FluorophenylacetonitrileeMethanol Binary System

Table 5.28 Dielectric Relaxation Parameters for p-Fluorophenylacetonitrile (FPAN)eMethanol Binary System continued ε0

Vol. Fraction of FPAN 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

31.53 29.81 27.93 26.52 24.80 22.95 21.08 18.68 16.31 15.12 14.65

s (ps) 30 C 45.28 40.23 33.72 30.46 26.44 23.42 20.78 18.48 16.83 14.92 13.05

ε0 29.96 28.06 26.25 24.75 23.23 21.41 19.51 17.05 15.12 14.11 13.85

s (ps) 40 C 38.38 33.13 28.09 25.21 22.45 20.29 18.32 16.50 14.66 13.56 12.27

10°C 20°C 30°C 40°C

35

εs

30

25

20

15 0.0

0.2

0.4 0.6 0.8 Vol. fraction of p-flurophenylacetonitrile

FIGURE 5.31 Static permittivity for FPANemethanol binary system.

1.0

243

Dielectric Spectroscopic Study of Molecular Interaction

70 10°C 20°C 30°C 40°C

60

50

τ (ps)

CHAPTER 5:

40

30

20

10 0.0

0.2

0.4 0.6 0.8 Vol. fraction of p-flurophenylacetonitrile

1.0

FIGURE 5.32 Relaxation time for FPANemethanol binary system.

0

-1

-2

εΕ

244

-3

-4

10°C 20°C 30°C 40°C

-5

-6 0.0

0.2 0.4 0.6 Mole fraction of p-flurophenylacetonitrile

FIGURE 5.33 Excess permittivity for FPANemethanol binary system.

0.8

1.0

5.9 p-FluorophenylacetonitrileeMethanol Binary System

10°C 20°C 30°C 40°C

10

6

E

-1

(1/τ) (ps )

8

4 2 0 0.0

0.2 0.4 0.6 0.8 Mole fraction of p-flurophenylacetonitrile

1.0

FIGURE 5.34 Excess inverse relaxation time 103 FPANemethanol binary system.

Table 5.29 Bj Coefficients of RedlicheKister Equation for p-Flurophenylacetonitrile (FPAN)eMethanol Binary System Excess Permittivity Temp.  C

B0

10 20 30 40

9 8 6 4

B1 5 1 1 0

B2 10 10 12 18

B3 14 12 16 15

Excess Inv. Relax. Time B0 3 10

3

56 50 44 35

B1 3 103

B2 3 103

B3 3 103

21 12 15 21

37 21 8 10

29 2 12 18

Table 5.30 Kirkwood Correlation Factor geff for p-Fluorophenylacetonitrile (FPAN)eMethanol Binary System geff Vol. Fraction of FPAN

10 C

20 C

30 C

40 C

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

3.27 2.53 2.05 1.70 1.47 1.22 1.03 0.86 0.68 0.52 0.48

3.20 2.44 1.99 1.63 1.44 1.18 1.00 0.83 0.64 0.51 0.48

3.11 2.38 1.90 1.57 1.39 1.14 0.95 0.80 0.61 0.51 0.47

3.02 2.32 1.81 1.51 1.33 1.08 0.91 0.76 0.58 0.49 0.47

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Table 5.31 Activation Energy for p-Fluorophenylacetonitrile (FPAN)e Methanol Binary System Vol. Fraction of FPAN

Activation Energy (DH), kJ/mol

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

6.30 13.57 15.24 15.13 14.46 12.65 11.67 8.93 7.65 6.57 5.60

1.0 10°C 20°C 30°C 40°C Theo.

0.8

0.6

fB

246

0.4

0.2

0.0 0.0

0.2

0.4

0.6

0.8

1.0

Vol. fraction of p-flurophenylacetonitrile

FIGURE 5.35 Bruggeman factor for FPANemethanol binary system. The Bruggeman parameter “a” is found to be 1.361, 1.268, 1.134, and 1.014 at 10, 20, 30, and 40 C, respectively, for p-fluorophenylacetonitrileemethanol binary system.

References

5.10

OTHER SIMILAR SYSTEMS

1. Butanenitrilee1,2-dichloroethane13 2. Methanolenitrile11 3. Nitrile solubilized by sodium dodecyl in aqueous solutions9

5.11

CONCLUSIONS

In this chapter, dielectric properties of binary mixtures of nonhydrogenbonded liquids (nitriles) and hydrogen-bonded liquids (water, methanol) are given using time domain reflectometry technique in the frequency range of 10 MHz to 10 GHz. For pure nitriles, static permittivity decreases and relaxation time increases with an increase in the number of carbon atoms in the chain. Comparison of the static permittivity and relaxation time for nitriles and alcohols shows that as in the case of n-alcohols, static permittivity also decreases with a number of carbon atoms in n-nitriles. Similarly, relaxation time increases with an increase in the number of carbon atoms in nitriles as well as alcohols. From the values of relaxation times, due to hydrogen bonding, molecules do not rotate easily in case of alcohols, which leads to very high relaxation time, whereas in case of n-nitriles due to nonhydrogen bonding, molecules rotate easily resulting in smaller values of relaxation time. The change in static permittivity with an increase in number of carbon atoms in a chain is the same for n-nitriles and n-alcohols but the change in relaxation time with an increase in number of carbon atoms in a chain is very small for n-nitriles compare to n-alcohols. This shows that in n-nitriles intermolecular interaction is less. Therefore, relaxation time for n-nitriles is very small compared to n-alcohols. The nitrile systems have reduced tendency to disturb the hydrogen bonding with an increase of molecular size. The Kirkwood correlation factor for all nitrileewater and nitrileemethanol systems decreases with an increase in concentration of nitriles. The Kirkwood correlation factor is less than one in all pure nitriles. The dipoleedipole interaction in the nitrile liquids seems to be responsible for antiparallel alignment of dipoles since the hydrogen-bonding interactions are not possible in these liquids.

References 1. Helambe SN, Lokhande MP, Kumbharkhane AC, Mehrotra SC, Doraiswamy S. Pramana 1995; 44:405e10. 2. Helambe SN, Lokhande MP, Kumbharkhane AC, Mehrotra SC. Pramana 1995;45:19e24. 3. Helambe SN, Chaudhari A, Mehrotra SC. J Mol Liq 2000;84:235e44. 4. Helambe SN. Dielectric study of organic liquids with CN group at microwave frequency using computer aided time domain technique. 1993 [Ph.D. Thesis], Dr. B. A. M. University, Aurangabad, India.

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248

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5. Dannhauser W, Flueckinger AF. J Phys Chem 1964;68:1814e9. 6. Schlundt H. J Phys Chem 1901;5:157e69. 7. Eloranta JK, Kadaba PK. Trans Faraday Soc 1970;66:817e23. 8. Eloranta JK, Kadaba PK. Chem Phys Lett 1971;11:251e4. 9. Kalaivani T, Undre P, Sabesan R, Krishnan S. J Mol Liq 2012;172:76e80. 10.

Madan MP. Can J Phys 1987;65:1573e6.

11.

Madhurima V, Sobhanadri J, Murthy VRK. Ind J Pure Appl Phys 2004;42:837e40.

12.

Moumouzlas G, Panopoulos DK, Ritzoulis G. J Chem Engg Data 1991;36:20e3.

13.

Shere IG, Pawar VP, Mehrotra SC. Arch Appl Sci Res 2012;4:947e50.

14.

Hosamani MT, Fattepur RH, Deshpande DK, Mehrotra SC. J Chem Soc Faraday Trans 1995;91: 623e6.

15.

Gagliardi LG, Castells CB, Ràfols C, Rosés M, Bosch E. J Chem Eng Data 2007;52:1103e7.

16.

Subramanian M, Thenappan T, Parthipan G. Philos Mag Lett 2008;88:889e95.

17.

Weast RC. Handbook of chemistry and physics. 64th ed. Boca Raton, FL: CRC Press; 1983e84.