Feasibility Evaluation of Quinary Heterogeneous Reactive Extractive Distillation

Abstract

This study addresses a feasibility evaluation method for the heterogeneous reactive extractive distillation of azeotropic quinary mixtures based on visualization in composition space. A critical composition region, that is, thermodynamically infeasible region for heterogeneous reactive extractive distillation, is determined by the constraint of reaction and phase equilibria. In addition, operating constraints are imposed on the feasibility evaluation in terms of the upper and lower internal reflux boundaries. Using these two kinds of feasibility constraints, we examine how the ethyl and isopropyl acetate reactive distillation systems, which cannot produce pure products because of four minimum-boiling azeotropes, lead to a full conversion and pure product recovery with the introduction of an external entrainer inducing L−L splits. The pure acetate production in a single reactive extractive distillation column is possible because the composition trajectory approaches the desired region in composition space without being blocked by both the critical composition region and the infeasible region confined by the internal reflux boundaries.

Enhanced Energy Savings from Simultaneous Triple Esterification of C4–C6 Alcohols in a Single Reactive Distillation Column

“…The main issue for checking the feasibility of integrating V–L–L separation and reaction is that this integration can lead to the pure product recovery and the complete conversion of the reaction. − The feasibility criteria of RD processes with a single reaction have been well established using the dynamic properties of singular points in phase equilibrium diagrams and reaction equilibrium information . However, determining the feasibility of multiple reactions and distillation is quite challenging because it is hard to visualize the reaction equilibrium and phase equilibrium in the visible composition space.…”

“…25−28 The feasibility criteria of RD processes with a single reaction have been well established using the dynamic properties of singular points in phase equilibrium diagrams and reaction equilibrium information. 29 However, determining the feasibility of multiple reactions and distillation is quite challenging because it is hard to visualize the reaction equilibrium and phase equilibrium in the visible composition space.…”

Prediction of Main Regime Transition with Variations of Gas and Liquid Phases in a Bubble Column

“…The bubble column is an important gas–liquid contactor. It has been widely applied, such as in the petrochemical and mineral processing industries as well as in biomass production, because of their superior mass and heat transfer, simple construction, and flexible operation under various reaction conditions. − A bubble column consists of a main body column and a gas sparger at the bottom of the column. Gas is distributed through the gas sparger, and gas–liquid flow development occurs upon introduction to the column.…”

A fixed point methodology for the design of reactive distillation columns

“…However, this design method only can be used to one feed stream because of the limitation of the design equations. Conventional graphical techniques (Guo et al, 2004;Kang et al, 2014;Lee, 2002) has been developed to the double feed streams and reactive extractive distillation, which is the next research point of the modified fixed point method.…”