Performance Evaluation of Pervaporation Technology for Process Intensification of Butyl Acrylate Synthesis

Pervaporation-based hybrid processes have been investigated to overcome the drawbacks of equilibrium-limited reactions. Pervaporation processes are strongly recommended for heat-sensitive products and azeotropic mixtures as in the butyl acrylate system case, since pervaporation can operate at lower temperatures than distillation. In this work, experimental pervaporation data for multicomponent mixtures in the absence of reaction were measured for the compounds involved in the esterification reaction of acrylic acid with n-butanol at different temperatures: 323, 353, and 363 K. A commercial tubular microporous silica membrane from Pervatech was used which is highly selective to water, and its performance was evaluated by studying several parameters, like the selectivity, permeate fluxes, driving force of species, and separation factor. The effects of temperature and feed composition were assessed for binary, ternary, and quaternary mixtures. Increasing the temperature increases significantly the total permeate flux as well as the separation factor, which is higher for quaternary mixtures. The presence of butyl acrylate and acrylic acid reduces the total permeate flux since these molecules hinder the water permeation. The permeance of each species was correlated with temperature according to the Arrhenius equation, and a mathematical model was proposed to develop an integrated reaction separation process using the experimental data obtained. The reaction conversion of the fixed-bed membrane reactor at steady state achieved 98.7% at isothermal conditions, increasing by 66% the conversion obtained in a fixed bed reactor (at the same operating conditions).