Enthalpies for ethylbenzene, isooctane and ethylcyclohexane in the fluid state

Abstract

An electrical-matching, flow calorimeter was used to measure the enthalpies of ethylbenzene (349-551 K, 1.5-200 bar), Isooctane (358-520 K, 20-100 bar), and ethylcyclohexane (335-576 K, 20-100 bar). Water/steam calibration measurements show the apparatus capable of 0.1-0.2% precision with no detectable systematic bias.The present measurements are shown to be accurate to ±0.25% In enthalpy and ±2% in heat capacity.Literature vapor pressures, heats of vaporization, and perfect gas state enthalpies, consistent with the present hydrocarbon enthalpies, are used with our results to provide pressure/enthalpy diagrams for both the liquid and vapor states.

High Temperature High Pressure Thermodynamic Measurements for Coal Model Compounds

“…H E =-4469.000188Xb 6 +13670.6146Xb 5 Figure 24 shows how the polynomial matches the experimental data. Table 5 gives the Cp values derived by Cp= ∆ H/ ∆ T, Figure 25 shows the Cp distributions as the temperature rises.…”

“…Castro-Gomez et al (2) presented a flow enthalpy-increment calorimeter, as A large variety of methods and procedures to measure the enthalpy increments of different kind of chemicals are available in the literature. Johnson et al (5) describe a Freon-11 boil-off calorimeter which was designed to measure the enthalpy increment of fluid up to 700 K and 200 bar. Karlsruhe (6) reports another design of flow calorimeter for the measurement of isobaric enthalpy increment (150 bar and 600 K), which can produce very good results.…”

High Temperature High Pressure Thermodynamic Measurements for Coal Model Compounds

“…The temperature of the liquid is raised to within 5 C of the desired experimental temperature. The feed then enters the second coil placed inside the main heater oven (4) where the temperature of the liquid stream is raised to the desired temperature before it enters the vapor-liquid equilibrium cell (5). The vapor and liquid flow rates out of the VLE cell are controlled by two control valves (23,24), placed in the respective lines.…”

“…A large variety of methods and procedures to measure the enthalpy increments of different kind of chemicals are available in the literature. Johnson et al (5) describe a Freon-11 boil-off calorimeter which was designed to measure the enthalpy increment of fluid up to 700 K and 200 bar. Karlsruhe (6) reports another design of flow calorimeter for the measurement of isobaric enthalpy increment (150 bar and 600 K), which can produce very good results.…”