2
0
2009
smi
bad
1
journal
Original
Smirnov, V. I.[Valeriy I.]
Badelin, V. G.[Valentin G.]
Thermochim. Acta
2009
2020-09-29
Enthalpies of solution of l-threonine in a (water + alcohol) mixture at 298.15K
The enthalpies of solution of l-threonine in the (water +methanol), (water + ethanol), (water + npropanol), and (water + i-propanol) mixtures, with an alcohol content up to 0.4 mol fractions, have been measured calorimetrically at T = 298.15K. The standard enthalpies of solution and transfer of l-threonine fromwater to an aqueous alcohol have been calculated. The effect of the structure properties of the mixed solvent on the specified enthalpy characteristics of l-threonine is discussed. The enthalpy coefficients of pairwise interactions between amino acid and alcohol molecules have been computed. It has been found that these coefficients become increasingly positive in the methanol, ethanol, n-propanol, and i-propanol consequence. A comparative analysis of the thermodynamic characteristics of dissolution of l-threonine and some other amino acids (glycine, l-alanine and l-valine) in the mixtures studied has been made.
Amino acids
Aqueous alcohols
Enthalpies of solution and transfer
10.1016/j.tca.2009.06.005
1-2
495
90-94
1
InChI=1S/C4H9NO3/c1-2(6)3(5)4(7)8/h2-3,6H,5H2,1H3,(H,7,8)/t2-,3+/m1/s1
AYFVYJQAPQTCCC-GBXIJSLDSA-N
L-threonine
(-)-threonine
[R-(R*,S*)]-2-amino-3-hydroxybutanoic acid
C4H9NO3
1
Commercial source
1
Crystallization from solution
Dried in a desiccator
Crystallization from solution
Dried in a desiccator
2
99
2
Estimated by the compiler
2
InChI=1S/CH4O/c1-2/h2H,1H3
OKKJLVBELUTLKV-UHFFFAOYSA-N
methanol
methyl alcohol
CH4O
1
Commercial source
1
Crystallization from solution
2
99.5
3
Estimated by the compiler
3
0.03
1
Karl Fischer titration
3
InChI=1S/C2H6O/c1-2-3/h3H,2H2,1H3
LFQSCWFLJHTTHZ-UHFFFAOYSA-N
ethanol
ethyl alcohol
C2H6O
1
Commercial source
1
99.5
3
Estimated by the compiler
2
0.05
1
Karl Fischer titration
4
InChI=1S/C3H8O/c1-2-3-4/h4H,2-3H2,1H3
BDERNNFJNOPAEC-UHFFFAOYSA-N
propan-1-ol
1-propanol
n-propanol
n-propyl alcohol
C3H8O
1
Commercial source
1
Crystallization from solution
2
99.5
3
Estimated by the compiler
3
0.03
1
Karl Fischer titration
5
InChI=1S/C3H8O/c1-3(2)4/h3-4H,1-2H3
KFZMGEQAYNKOFK-UHFFFAOYSA-N
propan-2-ol
2-propanol
isopropanol
isopropyl alcohol
sec-propyl alcohol
C3H8O
1
Commercial source
1
Crystallization from solution
2
99.5
3
Estimated by the compiler
3
0.04
1
Karl Fischer titration
6
InChI=1S/H2O/h1H2
XLYOFNOQVPJJNP-UHFFFAOYSA-N
water
H2O
1
Commercial source
1
Fractional distillation
2
99.99
4
Estimated by the compiler
1
2
1
1
1
6
1
Principal objective of the work
VVD
TRC
11/17/2009
1
Molar enthalpy of solution, kJ/mol
ISOPERIBOL
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
2
6
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
298.15
5
2
Pressure, kPa
Liquid
101
3
3
Molality, mol/kg
1
Liquid
0.01
1
1
Solvent: Molality, mol/kg
2
Liquid
1
0.712
3
1
11.15
4
1
0.14
1
1.357
4
1
11.78
4
1
0.14
1
2.034
4
1
12.56
4
1
0.15
1
2.837
4
1
13.11
4
1
0.16
1
4.117
4
1
14.93
4
1
0.18
1
5.529
4
1
15.99
4
1
0.2
1
7.371
4
1
16.98
4
1
0.21
1
10.302
5
1
18.18
4
1
0.22
1
10.882
5
1
18.2
4
1
0.22
1
16.067
5
1
19.55
4
1
0.24
1
24.303
5
1
20.16
4
1
0.25
1
35.716
5
1
20.92
4
1
0.26
2
3
1
1
1
6
1
Principal objective of the work
VVD
TRC
11/17/2009
1
Molar enthalpy of solution, kJ/mol
ISOPERIBOL
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
3
6
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
298.15
5
2
Pressure, kPa
Liquid
101
3
3
Molality, mol/kg
1
Liquid
0.01
1
1
Solvent: Molality, mol/kg
3
Liquid
1
0.721
3
1
11.51
4
1
0.14
1
1.452
4
1
12.78
4
1
0.16
1
2.368
4
1
13.65
4
1
0.17
1
3.437
4
1
14.59
4
1
0.18
1
4.512
4
1
15.99
4
1
0.2
1
5.435
4
1
17.23
4
1
0.21
1
7.616
4
1
18.79
4
1
0.23
1
9.011
4
1
19.96
4
1
0.24
1
12.268
5
1
20.91
4
1
0.26
1
17.247
5
1
21.51
4
1
0.26
1
24.089
5
1
20.69
4
1
0.25
1
34.344
5
1
19.19
4
1
0.24
3
4
1
1
1
6
1
Principal objective of the work
VVD
TRC
11/17/2009
1
Molar enthalpy of solution, kJ/mol
ISOPERIBOL
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
4
6
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
298.15
5
2
Pressure, kPa
Liquid
101
3
3
Molality, mol/kg
1
Liquid
0.01
1
1
Solvent: Molality, mol/kg
4
Liquid
1
0.733
3
1
11.68
4
1
0.14
1
1.215
4
1
12.25
4
1
0.15
1
1.982
4
1
13.57
4
1
0.17
1
2.726
4
1
14.71
4
1
0.18
1
3.375
4
1
15.54
4
1
0.19
1
4.028
4
1
16.02
4
1
0.2
1
4.815
4
1
16.96
4
1
0.21
1
6.021
4
1
17.89
4
1
0.22
1
8.878
4
1
18.82
4
1
0.23
1
13.417
5
1
18.89
4
1
0.23
1
18.749
5
1
17.81
4
1
0.22
1
26.796
5
1
16.56
4
1
0.2
4
5
1
1
1
6
1
Principal objective of the work
VVD
TRC
11/17/2009
1
Molar enthalpy of solution, kJ/mol
ISOPERIBOL
Liquid
Difference with the reference state, X-X(REF)
Pure solute at the same temperature and pressure
Crystal
5
6
1
Data file compiler
Propagation of evaluated standard uncertainties
95
Liquid
1
Temperature, K
Liquid
298.15
5
2
Pressure, kPa
Liquid
101
3
3
Molality, mol/kg
1
Liquid
0.01
1
1
Solvent: Molality, mol/kg
5
Liquid
1
0.715
3
1
11.93
4
1
0.15
1
1.181
4
1
12.74
4
1
0.16
1
1.742
4
1
13.85
4
1
0.17
1
2.581
4
1
15.04
4
1
0.18
1
3.356
4
1
16.19
4
1
0.2
1
4.285
4
1
18.16
4
1
0.22
1
5.387
4
1
18.83
4
1
0.23
1
6.417
4
1
18.98
4
1
0.23
1
9.149
4
1
19.83
4
1
0.24
1
12.838
5
1
20.78
4
1
0.25
1
17.966
5
1
20.22
4
1
0.25
1
25.659
5
1
19.06
4
1
0.23