Vapor Pressure, Heat Capacity, and Density along the Saturation Line, Measurements for Cyclohexanol, 2-Cyclohexen-1-one, 1,2-Dichloropropane, 1,4-Di-tert-butylbenzene, (±)-2-Ethylhexanoic Acid, 2-(Methylamino)ethanol, Perfluoro-n-heptane, and Sulfolane

Abstract

This paper reports measurements made for DIPPR Research Project 821 in the 1994 Project Year. Vapor pressures were measured to a pressure limit of 270 kPa or lower decomposition point for eight compounds using a twin ebulliometric apparatus. Liquid-phase densities along the saturation line were measured for each compound over a range of temperatures (ambient to a maximum of 548 K). A differential scanning calorimeter (DSC) was used to measure two-phase (liquid + vapor) heat capacities for each compound in the temperature region ambient to the critical temperature or lower decomposition point. Where possible, the critical temperature and critical density for each compound were determined experimentally. The results of the measurements were combined to derive a series of thermophysical properties including critical temperature, critical density, critical pressure, acentric factor, enthalpies of vaporization [within the temperature range (±50 K) of the vapor pressures], enthalpies of fusion if solid at ambient temperature, solubility parameter, and heat capacities along the saturation line. Wagner-type vapor-pressure equations were derived for each compound. In addition, the liquid-phase densities were compared with values derived using a four-term power series in either T or [(1 − T r)1/3]. All measured and derived values were compared with those obtained in a search of the literature. Recommended critical parameters are listed for each of the compounds studied. A “Rule-Of-Thumb” derived in the 1992 Project Year was used to estimate thermal decomposition temperatures by radical scission from a knowledge of the bond dissociation energy or vice versa.

Liquid heat capacity of aqueous sulfolane+2-amino-2-methyl-1-propanol solutions

“…As can be seen in Fig. 2, the values of C p obtained in this study were in good agreement with the literature values (Castagnolo et al, 1981;Steele et al, 1997). From the available C p data of sulfolane, a solid line was determined as a function of temperature according to:…”

“…The average absolute percentage deviation between the calculated and the measured C p of sulfolane were 0.2 and 0.3%, respectively, for the values obtained in this study and those of Steele et al (1997).…”

“…The heat capacities of sulfolane were measured for temperatures ranging from 303.15 to 353.15 K. The measured C p of sulfolane along with the literature values (Castagnolo et al, 1981;Steele et al, 1997) is presented in Table 1. As can be seen in Fig.…”

Heat capacity, thermal conductivity and thermal diffusivity of aqueous sulfolane solutions

“…Saleh et al [5] reported the atmospheric pressure densities and viscosities of water + sulfolane mixtures in the entire composition range at temperatures ranging from (303.15 to 323.15) K. Steele et al [6] reported heat capacity, vapor pressure, and density along the saturation line, measurements for cyclohexane-1-one, 1,2-dichloro-propane, 1,4-ditert-butylbenzene, (±)-2-ethylhexanoic, 2-(methylamino)ethanol, perfluoro-n-heptane, and sulfolane. Castagnolo et al [7] measured heat capacities of binary liquid mixtures of water-sulfolane and water-hexamethylphosphotriamide.…”

A New Process for Synthesis of γ‐Butyrolactone and Cyclohexanone

“…The critical temperature T C and pressure P C of each component used in the present work is cited from references [42][43][44]. Fig.…”