Potential of Pervaporation-Based Dehydration Processes as an Equilibrium-Limited Reactions Enhancer: Proof-of-Concept and Process Scale-up for an Acrylic Ester

Chemicals derived from equilibrium-limited reactions represent a huge challenge mainly from the process sustainability point of view. Usually, high temperatures are required to reach reasonable kinetic rates and interesting yields. Apart from a high energy demand and operating costs, some of those compounds are temperature-sensitive, such as butyl acrylate, for instance, which polymerizes above 100 °C. Therefore, other alternatives have been investigated to attain competitive yields from the industrial point of view, reducing the energy required through process intensification strategies. This work focuses on a strategy for combining an effective separation process with a reaction. Pervaporation technology was coupled with a fixed-bed reactor for the production of butyl acrylate while water is continuously removed from the reaction medium enabling a shift of the reaction equilibrium. This approach benefits complex reactions with limited operating temperature ranges, either because of product yield constraints or parallel reactions, such as the polymerization of acrylic acid and butyl acrylate. The benefits of membrane separation for this kind of reaction were addressed in this work, where the proof-of-concept was shown comparing the process operating with and without a membrane module. A significant difference in butyl acrylate molar composition was observed, which increased 16%, while the water molar composition decreased about 40%. Moreover, the mathematical model was validated successfully, and different operating parameters were evaluated by process simulation. All the results provided are considered valuable for the design of pervaporation-based process intensification strategies at a large scale working in continuous mode operation. Finally, a simple strategy comprising a coupled reaction–separation configuration at the industrial scale is proposed and assessed for the continuous manufacturing of butyl acrylate.