SLLE and SLLVE of the water + NH 4 Cl + 1-propanol system at 101.3 kPa

Abstract

• Multiphase equilibrium for water+1-propanol+NH 4 CL • LL, SL and SLL and LLV, SLV and SLLV equilibrium data are determined at 298.15 K and at boiling temperature • Inconsistency of previous results is shown • Results are compared with the equilibrium phase diagram of water + NaCl + 1-propanol • Extended UNIQUAC modeling of three-phase equilibrium including solid

Influence of the temperature on the equilibrium phase diagram of the ternary system water + ammonium chloride + 2-propanol at 101.3 kPa

“…The boundaries of the LV, SLV, LLV and SLLV regions are plotted in Figure 2, where solid tie lines are used in the LLV and SLV regions and dashed lines to join the liquid phases with the compositions of the vapors in equilibria. The shape of the equilibrium diagram is similar to those of previous studied systems containing a completely miscible pair water-alcohol [7,8] From an interpolation of the data in Table 3, we have drawn Figures 3 and 4, showing the boiling temperature isotherms and the iso-concentration curves of 2-propanol in the vapor phase. As was demonstrated previously [7], the construction of these figures constitutes the best way to check the consistency of the data.…”

“…Moreover, not only is the amount of previous experimental data insufficient and incomplete, but some of the published data [5,6] also contain great inconsistencies as it is demonstrated in Ref. [7,8].…”

Equilibrium diagram of the water + K2SO4 or Na2SO4 + 1-propanol or 2-propanol systems at boiling conditions and 101.3 kPa

“…Their SLL equilibrium data at 353.15 K are represented in Figure 2. Mills and Smith [16] also determined liquid-liquid equilibrium data for the system with 2-propanol at 313.15 and 333.15 K. As in the systems with K2SO4, the temperatures used in the present work are higher than those but follow the trends of the previous data within the uncertainty of the measurements as can be seen in Figure . In previous works, the equilibrium diagrams of water + NaCl/KCl/NH4Cl + 1-propanol or 2propanol systems [7][8][9][10][11] were determined at boiling temperatures and 101.3 kPa. All these systems, where monovalent salts were involved, showed liquid-liquid phase splitting at the boiling point and even at lower temperatures, giving rise to ATPSs.…”

“…In previous works, the solid-liquid-liquid-vapor (SLLV) equilibrium diagrams of mixtures of water and 1-propanol or 2-propanol with different monovalent salts such as NaCl [7][8], KCl [9] or NH4Cl [10][11] have been studied under boiling conditions at 101.3 kPa. The objective of this work is to study the SLLV equilibrium of water + salt + alcohol systems where the considered salts are divalent.…”

Use of Ultrasound in the Determination of Isobaric LLV, SLV, and SLLV Equilibrium Data. Application to the Determination of the Water + Na2SO4 or K2SO4 + 2-Methylpropan-2-ol Systems at 101.3 kPa and Boiling Conditions

“…In addition to the mass transfer required to reach the equilibrium state between the liquid phases and between the liquid and the vapor, the mass transfer between the solid and the liquid phase should be enhanced. Ultrasonic waves can also be used, as shown previously [8][9][10] . As in the case of LLV equilibrium, the ultrasonics promote a dispersion of the phases and increase the mass transfer between them.…”