This article studies the consecutive transesterification of dimethyl carbonate with ethanol to form ethyl methyl carbonate and diethyl carbonate. The chemical equilibrium and reaction kinetics of this system are investigated experimentally and theoretically. To enhance the reaction rate, the homogeneous catalyst sodium ethoxide was applied. Molar-based and activity-based chemical equilibrium constants were calculated from experimental results, and their temperature dependence was described using the van't Hoff equation. An activity-based kinetic model that considers the temperature dependence of the reaction rate constants with the Arrhenius equation was derived.

Due to a high risk of polymerization and complex thermodynamic behavior of the chemical system, the current production process for n-butyl acrylate synthesis is cost-intensive and challenging. Reactive distillation integrates chemical reactions and distillation into one unit at the same time and is one of the best-known examples of process intensification. To facilitate industrial application of this concept for the production of n-butyl acrylate, reliable experimental data are required. This article presents an experimental and theoretical investigation of the synthesis of n-butyl acrylate using reactive distillation. Experiments were conducted in a pilot-scale reactive distillation column, and the decisive operational parameters were varied. To predict the experimental results, a nonequilibrium-stage model was applied and the model was validated using the experimental data. The validated model was then used to perform a process analysis, showing trends in the conversion of acrylic acid and n-butanol and the purity of n-butyl acrylate that can be used for prospective optimization studies.

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This work presents a feasibility study for an enzymatic reaction in a continuously operated reactive distillation column. As a model reaction, the transesterification of ethyl butyrate with n-butanol in the presence of lipase CALB was considered. For use in the distillation column, lipase CALB was immobilized by entrapment in a hydrophobic silica xerogel and introduced as granulate into the catalytic packing Katapak-SP-11. The reaction kinetics was experimentally determined for different concentration and temperature ranges and described by means of the Michaelis−Menten double-substrate kinetic model in combination with the Arrhenius model. With these kinetic data, process simulations were carried out with an Aspen Custom Modeler nonequilibrium-stage model validated for a DN50 pilot-scale column. The concentration of n-butanol in the reactive section was maintained low to decrease the inhibiting effects on the enzyme. For an optimized setup and operating conditions, conversion rates of more than 90% were achieved for n-butanol and 26% for ethyl butyrate. These results clearly demonstrate that lipase CALB can be applied in a continuously operated reactive distillation column.