Liquid-liquid equilibrium for the quaternary system propionic acid + n-propanol + n-propyl propionate + water at 293.15, 313.15 and 333.15 K

Abstract

Please cite this article as: A. Samarov, M. Toikka, M. Trofimova, A. Toikka, Liquid-liquid equilibrium for the quaternary system propionic acid + n-propanol + n-propyl propionate + water at 293.15, 313.15 and 333.15 K, Fluid Phase Equilibria (2016), AbstractLiquid-liquid equilibrium (LLE) for the quaternary system propionic acid + n-propanol + n-propyl propionate + water and for the ternary sub-systems propionic acid + n-propyl propionate + water and n-propanol + n-propyl propionate + water were studied at 293.15, 313.15 and 333.15 K and atmospheric pressure. Binodal surface in quaternary system and binodal curves in ternary systems were determined. Experimental LLE data were compared with the values calculated by NRTL models, these data are in good agreement.Keywords: Liquid-liquid equilibria, n-propyl propionate, NRTL model IntroductionThe data on phase diagrams of heterogeneous systems are of well-known importance for the design of modern industrial processes. n-Propyl propionate is one of commonly used solvents having a lot of practical applications. This ester is used in many different fields, for example, as a constituent part of coatings, printing inks, air freshener, confecting essence, detergent and other industrial products. n-Propyl propionate is readily biodegradable and it is expected to be rapidly degraded in wastewater treatment plants or in the environment [1]. n-Propyl propionate is generally synthesized by the esterification reaction of propionic acid with n-propanol. The complex process of its production involves reaction and separation operations. One of the best and well-known chemical engineering processes which combines chemical reaction and separation into a multifunctional reactor is a reactive distillation [2] and [3]. The limited mutual solubility of components of n-propyl propionate synthesis reaction should be taken into account in reactive distillation design. For example, one can use the advantage of the phase splitting by coupling the distillation column with a liquid-liquid separator [4]. For this reason the majority of recent papers on n-propyl propionate production include the discussion of the splitting in propionic acid + n-propanol + n-propyl propionate + water system [1,[4][5][6][7][8][9][10]. Nevertheless the available experimental data sets on LLE were presented for binary sub-systems and for ternary n-propanol + water + n-propyl propionate system only [11]. The LLE in this ternary system was studied by Altman et al at 288.15 K [5] and by Mozzhukhin et al at 293.15 K [12]. The aim of our work was to study LLE for quaternary system propionic acid + n-propanol + n-propyl propionate + water and for both ternary sub-system propionic acid + n-propyl propionate + water and n-propanol + n-propyl propionate + water with miscibility gap at three temperatures, 293.15, 313.15 and 333.15 K. The sets of obtained experimental data gave us the opportunity to present in more details the binodal surface and tielines position of the system with n-propyl propionate synthesis reaction in com...

Experimental Liquid–Liquid Equilibrium and Solubility Study of an Acetic Acid–n-Propyl Alcohol–n-Propyl Acetate–Water System at 323.15 and 333.15 K

“…The shape of the surface itself is quite common: this is an ellipsoid segment. Other similar quaternary systems that we previously studied have a similar form of the binodal surface: formic acid–ethyl alcohol–ethyl formate–water, acetic acid–ethyl alcohol–ethyl acetate–water, propionic acid–ethyl alcohol–ethyl propionate–water, and propionic acid– n -propyl alcohol– n -propyl propionate–water …”

“…Other similar quaternary systems that we previously studied have a similar form of the binodal surface: formic acid−ethyl alcohol−ethyl formate−water, 36 acetic acid−ethyl alcohol−ethyl acetate−water, 31 propionic acid−ethyl alcohol−ethyl propionate−water, 34 and propionic acid−n-propyl alcohol−n-propyl propionate−water. 37 To compare experimental LLE results for the binary system n-propyl acetate−water with the literature data, 11,14,17,38,39 a diagram of the concentration of propyl acetate on temperature was plotted (Figure 7).…”

A Complete Heterogeneous Model for the Production of n-Propyl Propionate Using a Simulated Moving Bed Reactor

“…where n c is the number of components, g ij measures component i and j interactions, and α ij measures the lack of randomness. The value of 0.3 is adopted for α ij obtained from Samarov et al (2016) [20], and g ij are the thermodynamic parameters to be estimated. The mass transfer coefficient, K L,ik , is given by the following [18,21]:…”

“…The concentration of component i in section k in the adsorbed phase, q i,k in equilibrium with the fluid phase concentration, c i,k is given by the Langmuir adsorption isotherm equation for liquid phase adsorption [18][19][20]:…”

“…Thermodynamic experimental data were obtained from Samarov et al (2016)'s LLE at 313.15 K [20]. The authors estimated the thermodynamic parameters within a temperature range from 293.15 to 333.15.…”