11.4 SEPARATION METHODS

Boiling

Solvent strength parameter

Viscosity,

Refractive

point,

mN · s · m 2

index

UV

Solvent

C

e (SiO2 )

e (Al 2 O3 )

(20 C)

(20 C)

cutoff, nm

Fluoroalkanes

0.25

1.25

Pentane

36

0.0

0.0

0.24

15 C

1.358

210

Hexane

69

0.0

0.0

0.31

1.375

210

2,2,4-Trimethylpentane

99

0.01

0.50

1.392

215

Decane

174

0.04

0.93

1.412

210

Cyclohexane

81

0.05

0.04

0.98

1.426

210

Cyclopentane

49

0.05

0.44

1.407

210

Diisobutylene

101

0.06

1.411

1-Pentene

30

0.08

0.24

0 C

1.371

Carbon disulfide

46

0.14

0.15

0.36

1.626

380

Carbon tetrachloride

77

0.14

0.18

0.97

1.466

265

1-Chlorobutane

78

0.26

0.43

1.402

220

1-Chloropentane

98

0.26

0.58

1.412

225

o -Xylene

144

0.26

0.81

1.505

290

Diisopropyl ether

68

0.28

0.38

25 C

1.369

220

2-Chloropropane

35

0.29

0.33

1.378

225

Toluene

111

0.29

0.59

1.497

286

1-Chloropropane

47

0.30

0.35

1.389

225

Chlorobenzene

132

0.40

0.80

1.525

Benzene

80

0.25

0.32

0.65

1.501

280

Bromoethane

38

0.37

0.40

1.424

16.11

TABLE 11.11 Solvents of Chromatographic Interest

Continued

Boiling

Solvent strength parameter

Viscosity,

Refractive

point,

mN · s · m 2

index

UV

Solvent

C

e (SiO2 )

e (Al 2 O3 )

(20 C)

(20 C)

cutoff, nm

Diethyl ether

35

0.38

0.38

0.25

1.353

218

Diethyl sulfide

92

0.38

0.45

1.443

290

Chloroform

62

0.26

0.40

0.57

1.443

245

Dichloromethane

41

0.42

0.44

1.425

235

4-Methyl-2-pentanone

116

0.43

0.42

15 C

1.396

335

Tetrahydrofuran

66

0.45

0.55

1.407

220

1,2-Dichloroethane

84

0.49

0.80

1.445

228

2-Butanone

80

0.51

0.42

15 C

1.379

330

1-Nitropropane

131

0.53

0.80

25 C

1.402

380

Acetone

56

0.47

0.56

0.32

1.359

330

1,4-Dioxane

101

0.49

0.56

1.44

15 C

1.420

215

Ethyl acetate

77

0.38

0.58

0.45

1.372

255

Methyl acetate

56

0.60

0.48

15 C

1.362

260

1-Pentanol

138

0.61

4.1

1.410

210

Dimethyl sulfoxide

189

0.62

2.47

1.478

265

Aniline

184

0.62

4.40

1.586

Diethylamine

56

0.63

0.33

1.386

275

Nitromethane

101

0.64

0.67

1.394

380

Acetonitrile

82

0.50

0.65

0.37

1.344

190

Pyridine

115

0.71

0.97

1.510

330

2-Butoxyethanol

170

0.74

3.15

25 C

1.420

220

1-Propanol

97

0.82

2.25

1.386

210

2-Propanol

82

0.82

2.50

1.377

210

Ethanol

78

0.88

1.20

1.361

210

Methanol

65

0.95

0.59

1.328

210

Ethylene glycol

198

1.11

21.8

1.432

210

Acetic acid

118

large

1.23

1.372

260

Water

100

large

1.00

1.333

191

17.11

11.18

SECTION

11

TABLE 11.12 Solvents Having the Same Refractive Index and the Same Density at 25

C

Refractive

index

Density, g/mL

Solvent 1

Solvent 2

1

2

1

2

Acetone

Ethanol

1.357

1.359

0.788

0.786

Ethyl formate

Methyl acetate

1.358

1.360

0.916

0.935

Ethanol

Propionitrile

1.359

1.363

0.786

0.777

2,2-Dimethylbutane

2

-Methylpentane

1.366

1.369

0.644

0.649

2-Methylpentane

Hexane

1.369

1.372

0.649

0.655

Isopropyl acetate

2-Chloropropane

1.375

1.376

0.868

0.865

3-Butanone

Butyraldehyde

1.377

1.378

0.801

0.799

Butyraldehyde

Butyronitrile

1.378

1.382

0.799

0.786

Dipropyl ether

Butyl ethyl ether

1.379

1.380

0.753

0.746

Propyl acetate

Ethyl propionate

1.382

1.382

0.883

0.888

Propyl acetate

1-Chloropropane

1.382

1.386

0.883

0.890

Butyronitrile

2-Methyl-2-propanol

1.382

1.385

0.786

0.781

Ethyl propionate

1-Chloropropane

1.382

1.386

0.888

0.890

1-Propanol

2-Pentanone

1.383

1.387

0.806

0.804

Isobutyl formate

1-Chloropropane

1.383

1.386

0.881

0.890

1-Chloropropane

Butyl formate

1.386

1.387

0.890

0.888

Butyl formate

Methyl butyrate

1.387

1.391

0.888

0.875

Methyl butyrate

2-Chlorobutane

1.392

1.395

0.875

0.868

Butyl acetate

2-Chlorobutane

1.392

1.395

0.877

0.868

4-Methyl-2-pentanone

Pentanonitrile

1.394

1.395

0.797

0.795

4-Methyl-2-pentanone

1-Butanol

1.394

1.397

0.797

0.812

2-Methyl-1-propanol

Pentanonitrile

1.394

1.395

0.798

0.795

2-Methyl-1-propanol

2-Hexanone

1.394

1.395

0.798

0.810

2-Butanol

2,4-Dimethyl-3-pentanone

1.395

1.399

0.803

0.805

2-Hexanone

1-Butanol

1.395

1.397

0.810

0.812

Pentanonitrile

2,4-Dimethyl-3-pentanone

1.395

1.399

0.795

0.805

2-Chlorobutane

Isobutyl butyrate

1.395

1.399

0.868

0.860

Butyric acid

2-Methoxyethanol

1.396

1.400

0.955

0.960

1-Butanol

3-Methyl-2-pentanone

1.397

1.398

0.812

0.808

1-Chloro-2-methylpropane

Isobutyl butyrate

1.397

1.399

0.872

0.860

1-Chloro-2-methylpropane

Pentyl acetate

1.397

1.400

0.872

0.871

Methyl methacrylate

3-Methyl-2-pentanone

1.398

1.398

0.795

0.808

Triethylamine

2,2,3-Trimethylpentane

1.399

1.401

0.723

0.712

Butylamine

Dodecane

1.399

1.400

0.736

0.746

Isobutyl butyrate

1-Chlorobutane

1.399

1.401

0.860

0.875

1-Nitropropane

Propionic anhydride

1.399

1.400

0.995

1.007

Pentyl acetate

1-Chlorobutane

1.400

1.400

0.871

0.881

Pentyl acetate

Tetrahydrofuran

1.400

1.404

0.871

0.885

Dodecane

Dipropylamine

1.400

1.400

0.746

0.736

1-Chlorobutane

Tetrahydrofuran

1.401

1.404

0.871

0.885

Isopentanoic acid

2-Ethoxyethanol

1.402

1.405

0.923

0.926

Dipropylamine

Cyclopentane

1.403

1.404

0.736

0.740

2-Pentanol

4-Heptanone

1.404

1.405

0.804

0.813

3-Methyl-1-butanol

Hexanonitrile

1.404

1.405

0.805

0.801

3-Methyl-1-butanol

4-Heptanone

1.404

1.405

0.805

0.813

Hexanonitrile

4-Heptanone

1.405

1.405

0.801

0.813

Hexanonitrile

1-Pentanol

1.405

1.408

0.801

0.810

Hexanonitrile

2-Methyl-1-butanol

1.405

1.409

0.801

0.815

4-Heptanone

1-Pentanol

1.405

1.408

0.813

0.810

PRACTICAL

LABORATORY INFORMATION

11.19

TABLE 11.12 Solvents Having the Same Refractive Index and the Same Density at 25

C ( Continued

)

Refractive

index

Density, g/mL

Solvent 1

Solvent 2

1

2

1

2

2-Ethoxyethanol

Pentanoic acid

1.405

1.406

0.926

0.936

2-Heptanone

1

-Pentanol

1.406

1.408

0.811

0.810

2-Heptanone

2

-Methyl-1-butanol

1.406

1.409

0.811

0.815

2-Heptanone

Dipentyl ether

1.406

1.410

0.811

0.799

2-Pentanol

3-Isopropyl-2-pentanone

1.407

1.409

0.804

0.808

1-Pentanol

Dipentyl ether

1.408

1.410

0.810

0.799

2-Methyl-1-butanol

Dipentyl ether

1.409

1.410

0.815

0.799

Isopentyl isopentanoate

Allyl alcohol

1.410

1.411

0.853

0.847

Dipentyl ether

2-Octanone

1.410

1.414

0.799

0.814

2,4-Dimethyldioxane

3-Chloropentene

1.412

1.413

0.935

0.932

2,4-Dimethyldioxane

Hexanoic acid

1.412

1.415

0.935

0.923

Diethyl malonate

Ethyl cyanoacetate

1.412

1.415

1.051

1.056

3-Chloropentene

Octanoic acid

1.413

1.415

0.932

0.923

2-Octanone

1-Hexanol

1.414

1.416

0.814

0.814

2-Octanone

Octanonitrile

1.414

1.418

0.814

0.810

3-Octanone

3-Methyl-2-heptanone

1.414

1.416

0.830

0.818

3-Methyl-2-heptanone

1-Hexanol

1.415

1.416

0.818

0.814

3-Methyl-2-heptanone

Octanonitrile

1.415

1.418

0.818

0.810

1-Hexanol

Octanonitrile

1.416

1.418

0.814

0.810

Dibutylamine

Allylamine

1.416

1.419

0.756

0.758

Allylamine

Methylcyclohexane

1.419

1.421

0.758

0.765

Butyrolactone

1,3-Propanediol

1.434

1.438

1.051

1.049

Butyrolactone

Diethyl maleate

1.434

1.438

1.051

1.064

2-Chloromethyl-2-

Diethyl maleate

1.436

1.438

1.059

1.064

propanol

N

-Methylmorpholine

Dibutyl decanedioate

1.436

1.440

0.924

0.932

1,3-Propanediol

Diethyl maleate

1.438

1.438

1.049

1.064

Methyl salicylate

Diethyl sulfide

1.438

1.442

0.836

0.831

Methyl salicylate

1-Butanethiol

1.438

1.442

0.836

0.837

1-Chlorodecane

Mesityl oxide

1.441

1.442

0.862

0.850

Diethylene glycol

Formamide

1.445

1.446

1.128

1.129

Diethylene glycol

Ethylene glycol diglycidyl

1.445

1.447

1.128

1.134

ether

Formamide

Ethylene glycol diglycidyl

1.446

1.447

1.129

1.134

ether

2-Methylmorpholine

Cyclohexanone

1.446

1.448

0.951

0.943

2-Methylmorpholine

1-Amino-2-propanol

1.446

1.448

0.951

0.961

Dipropylene glycol mono-

Tetrahydrofurfuryl alcohol

1.446

1.450

1.043

1.050

ethyl ether

1-Amino-2-methyl-2-

2-Butylcyclohexanone

1.449

1.453

0.904

0.901

pentanol

2-Propylcyclohexanone

4-Methylcyclohexanol

1.452

1.454

0.923

0.908

Carbon tetrachloride

4,5-Dichloro-1,3-

1.459

1.461

1.584

1.591

dioxolane-2-one

N

-Butyldiethanolamine

Cyclohexanol

1.461

1.465

0.965

0.968

D

- -Pinene

trans

-Decahydro-

1.464

1.468

0.855

0.867

naphthalene

Propylbenzene

p -Xylene

1.490

1.493

0.858

0.857

Propylbenzene

Toluene

1.490

1.494

0.858

0.860

11.20

SECTION

11

TABLE 11.12 Solvents Having the Same Refractive Index and the Same Density at 25

C (

Continued

)

Refractive

index

Density, g/mL

Solvent 1

Solvent 2

1

2

1

2

Phenyl 1-hydroxyphenyl

1,3-Dimorpholyl-2-

1.491

1.493

1.081

1.094

ether

propanol

Phenetole

Pyridine

1.505

1.507

0.961

0.978

2-Furanmethanol

Thiophene

1.524

1.526

1.057

1.059

m -Cresol

Benzaldehyde

1.542

1.544

1.037

1.041

TABLE 11.13

McReynolds’ Constants

for Stationary

Phases in Gas Chromatography

Temp.,

C

McReynolds’ constants

Similar stationary

USP

Stationary phase

Chemical

type

phases

Min

Max

x ’

y ’

z ’

u ’

s ’

code

Boiling-point separation of broad molecular weight range of compounds; nonpolar phases

Squalane

2,6,10,15,19,23-Hexa-

20

150

0

0

0

0

0

0

methyltetracosane

Paraffin oil

9

5

2

6

11

33

Apiezon

L

50

300

32

22

15

32

42

143

SPB-1

Poly(dimethylsiloxane)

SA-1, DB-1

60

320

4

58

43

56

38

199

SP -2100

Poly(dimethylsiloxane)

DC-200, SE 30, UC

0

350

17

57

45

67

43

229

G 9

W98, DC 200

OV-1

Methylsiloxane gum

100

350

16

55

44

65

42

227

G 2

OV-101

Methylsiloxane fluid

20

350

17

57

45

67

43

234

G 1

SPB-5

1% Vinyl, 5% phenyl

SA-5, DB-5

60

320

19

74

64

93

62

312

methyl

polysiloxane

SE-54

1% Vinyl, 5% phenyl

PTE-5

50

300

19

74

64

93

62

312

G 36

methyl

polysiloxane

SE-52

5% Phenyl methyl

50

300

32

72

65

98

67

334

G 27

polysiloxane

OV-73

5.5% Phenyl methyl

SP-400

0

325

40

86

76

114

85

401

G 27

polysiloxane

OV-3

Poly(dimethyldiphenyl-

0

350

44

86

81

124

88

423

siloxane); 90%:10%

Dexsil

300

Carborane

9methyl

50

450

47

80

103

148

96

474

G 33

silicone

Dexsil

400

Carborane

9methyl-

50

400

72

108

118

166

123

587

21.11

phenyl

silicone

TABLE 11.13

McReynolds’ Constants for Stationary Phases in Gas Chromatography (

Continued

)

Temp.,

C

McReynolds’

constants

Similar stationary

USP

Stationary phase

Chemical type

phases

Min

Max

x ’

y ’

z ’

u ’

s ’

code

Boiling-point separation of broad molecular weight range of compounds; nonpolar phases

(

continued

)

OV-7

20% Phenyl methyl

DC 550

0

350

69

113

111

171

128

592

polysiloxane

SPB-20

20% Phenyl methyl

SPB-35, SPB-1701,

20

300

67

116

117

174

131

605

polysiloxane

DB-1301

Di-(2-ethylhexyl)-

20

125

72

168

108

180

125

653

G 11

sebacate

DC 550

25% Phenyl methyl

20

225

81

124

124

189

145

663

G 28

polysiloxane

Unsaturated hydrocarbons and other compounds of intermediate polarity

Diisodecyl

20

150

84

173

137

218

155

767

G 24

phthalate

OV-11

35% Phenyl methyl

0

350

102

142

145

219

178

786

polysiloxane

OV-1701

Vinyl methyl poly-

SPB-1701, SA-1701,

0

250

67

170

152

228

171

789

siloxane

DB-1701

Poly-I 110

275

115

194

122

204

202

837

G 37

SP-2250

Poly(phenylmethyl-

OV-17, DB-17

0

375

119

158

162

243

202

884

G 3

siloxane); 50% phenyl

Dexsil

410

Carborane— methylcyano

50

400

72

286

174

249

171

952

ethyl silicone

UCON

LB-550-X

Polyalkylene glycol

20

200

118

271

158

243

206

996

UCON LB-1880-X

Polyalkylene glycol

200

123

275

161

249

212

1020

G 18

Poly-A 103

275

115

331

144

263

214

1072

G 10

TABLE 11.13

McReynolds’ Constants for

Stationary Phases in Gas Chromatography (

Continued

)

Temp.,

C

McReynolds’

constants

Similar stationary

USP

Stationary phase

Chemical type

phases

Min

Max

x ’

y ’

z ’

u ’

s ’

code

Unsaturated hydrocarbons and other

compounds of intermediate polarity

(continued

)

OV-22

Poly(diphenyldimethyl-

0

350

160

188

191

283

253

1075

siloxane); 65%:35%

Di(2-ethylhexyl)

150

135

254

213

320

235

1157

G 22

phthalate

OV-25

Poly(diphenyldimethyl-

0

350

178

204

208

305

280

1175

G 17

siloxane); 75%:25%

Moderately polar

compounds

DC QF-1

0

250

144

233

355

463

305

1500

OV-210

50% Trifluoropropyl-

SP-2401, DB-210

0

275

146

238

358

468

310

1520

G 6

methylpolysiloxane

OV-215

Poly(trifluoropropyl-

0

275

149