Control Study of Ethyl tert-Butyl Ether Reactive Distillation

Abstract

Control structures for ethyl tert-butyl ether (ETBE) reactive distillation columns are studied. Two process configurations are explored: a design with two fresh reactant feed streams and a design with a single mixed reactant feed. An optimum design for the double-feed case is presented. A design given in the literature is used for the single-feed case. Several control structures are investigated, and their effectiveness in the ETBE case is compared with that in previously studied chemical systems. Results show that the double-feed system requires internal composition control to balance the stoichiometry, along with temperature control to maintain product purity. The single-feed case, which operates with an excess of ethanol, is effectively controlled with only a temperature controller provided disturbances are not too large.

Plantwide control for TAME production using reactive distillation

“…Both have two reactants, one product and light inerts. We studied the control of the ETBE reactive distillation "neat" operation in a previous article (Al-Arfaj and Luyben, 2002a). A control structure that consists of internal composition control of one of the reactants by the reactant feed rate and a temperature control of a tray in the stripping zone by the heat input was found to be effective.…”

Control of Quaternary Ideal Endothermic Reactive Distillation with and without Internal Heat Integration

“…Furthermore, using CS4 L/D , both designs are tested for 5 mol % feed impurity disturbances and the final steady-state values of the product purities are given in Tab. 5 …”

“…The separation often gets simplified via ''reacting away'' of azeotropes [2]. RD has thus been successfully implemented as a promising commercial alternative to the conventional schemes of ''reaction followed by separation'' for a large variety of reaction chemistries such as etherification [3][4][5], esterification [6,7] and hydration [8,9].…”

Simulation Studies of the Removal of Water From Ethanol by a Catalytic Distillation Process

“…The UNIFAC activity coefficient model for the liquid phase and the Redlich Kwong equation of state in the gas phase were used as the equilibrium models. The UNIFAC equation has been used successfully in the simulation of catalytic distillation columns for several similar reaction mixtures including ETBE=ethanol=butenes (Sneesby et al, 1997;Al-Arfaj and Luyben, 2002) and MTBE=methanol=butenes (Pilavachi et al, 1997).…”