Excess molar enthalpies of methylformate + (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) at T = 298.15 K, p = (5.0, 10.0) MPa, and methylformate + 1-propanol at T = 333.15 K, p = 10.0 MPa

doi:10.1016/j.tca.2005.11.041

Thermochimica Acta

Volume 443, Issue 1, 1 April 2006, Pages 125-128

https://doi.org/10.1016/j.tca.2005.11.041 Get rights and content

Abstract

A high pressure flow-mixing isothermal calorimeter is used to determine the excess molar enthalpies of methylformate + (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) at T = 298.15 K and p = (5.0, 10.0) MPa, and methylformate + 1-propanol at T = 333.15 K and p = 10.0 MPa. The Redlich–Kister equation is fit to the experimental results.

Introduction

For proper design of chemical processes and to test theories of solution, there is a constant need for thermodynamic excess enthalpy data. To determine the influence of temperature and pressure on the excess molar enthalpy, and to overcome the lack of the data on mixtures of ester and alcohols at high pressure, excess molar enthalpies of five binary systems for methylformate and (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) were determined at T = (298.15, 333.15) K and p = (5.0, 10.0) MPa. The excess molar enthalpy of methylformate and 1-propanol at T = 298.15 K and p = 0.1 MPa was reported in literature [1]. But the published $H_{m}^{E}$ data were determined at ambient pressure.

Section snippets

Chemicals

In all experiments, methylformate (A.R. grade) and alcohols (A.R. grade) were dried with the help of molecular sieves (3 Å) and filtered by Millipore filter (0.45 μm).

Apparatus

A commercial isothermal calorimeter (model IMC 4400, Calorimetry Sciences Corporation, USA) was used in these measurements. The flow-mixing system consists of a sample cell and a reference cell (model CSC 4442), two syringe pumps (model 260D, ISCO Inc., USA) with a resolution of 0.1 μL min⁻¹, and a back pressure regulator (model CSC

Results

Excess molar enthalpies of methylformate and (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) at T = (298.15, 333.15) K and p = (5.0, 10.0) MPa are listed in Table 1, Table 2, Table 3, Table 4, Table 5. Experimental results were fitted to a Redlich–Kister polynomial: $H_{m}^{E} = x (1 - x) \sum_{i = 0}^{N} A_{i} {(1 - 2 x)}^{i}$ Table 6 contains the parameters of Redlich–Kister equation and standard deviations (S.D.). The experimental data from Table 1, Table 2, Table 3, Table 4, Table 5 are plotted in Fig. 1, Fig. 2, Fig. 3.

Discussion

All the binary systems showed endothermic and symmetrical behavior over the whole mole fraction range. The explanation of the above behavior is thought to be steric interactions. The most important molecular associations in the pure liquids are through hydrogen bonds in the alcohols and dipole–dipole interactions between molecules of ester. The main interactions in the hydrogen bonds are those between the oxygen atoms of the ester group and hydrogen atoms of the alcohol hydroxyl group [3]. The

References (6)

R. Zhang et al.
Molar excess enthalpies of ethyl acetate + alkanols at T = 298.15 K, p = 10 MPa
Thermochim. Acta
(2005)
E. Romano et al.
Thermophysical properties of four binary dimethyl carbonate + 1-alcohol systems at 288.15–313.15 K
Fluid Phase Equilibr.
(2003)
H.Y. Yang et al.
Excess molar enthalpies of n-alkanols or isomeric alkanols + N,N-dimethlethanolamine at 298.15 K
Thermochim. Acta
(1995)

There are more references available in the full text version of this article.

Cited by (4)

Excess molar enthalpies of ethyl acetoacetate + (methanol, +ethanol, +1-propanol, and +2-propanol) at T= (298.15, 313.15 and 328.15) K and p = (0.1 and 10.0) MPa
2008, Fluid Phase Equilibria
The excess molar enthalpies of four binary systems for ethyl acetoacetate + (methanol, +ethanol, +1-propanol, and +2-propanol) at T = (298.15, 313.15, and 328.15) K and p = (0.1 and 10.0) MPa were determined by a high pressure flow-mixing isothermal microcalorimeter. The densities of ethyl acetoacetate at T = (278.15, 288.15, 298.15, 313.15, 328.15, 338.15, and 348.15) K were determined by pycnometer. The excess molar enthalpies increase with an increase in the temperature and the molecular size of alcohols and decrease with an increase in pressure. The experimental data were correlated by the Redlich–Kister equation and two local composition models (NRTL and UNIQUAC).
Nitrogen mineralization, soil microbial biomass and extracellular enzyme activities regulated by long-term n fertilizer inputs: A comparison study from upland and paddy soils in a red soil region of china
2021, Agronomy
Excess molar enthalpies of n,n-dimethylethanolamine with (methanol, ethanol, 1-propanol, and 2-propanol) at T = (298.2, 313.2, and 328.2) K and p = (0.1 and 10.0) MPa
2008, Journal of Chemical and Engineering Data
Determination and correlation of excess molar enthalpies of eight binary systems containing acetophenone at different temperatures
2008, Journal of Chemical and Engineering Data

View full text

Short communicationExcess molar enthalpies of methylformate + (1-propanol, 2-propanol, 1-butanol, 2-butanol and 1-pentanol) at T = 298.15 K, p = (5.0, 10.0) MPa, and methylformate + 1-propanol at T = 333.15 K, p = 10.0 MPa