Rational Design Method Based on Techno-Economic Principles for Integration of Organic/Organic Pervaporation with Lipase Catalyzed Transesterification.

Wouter Van Hecke,Pieterjan Debergh,Mohammed Nazeer Khan,Miet Van Dael

doi:10.3390/membranes11060407

Wouter Van Hecke, Pieterjan Debergh + Show 2 more

Open Access

https://doi.org/10.3390/membranes11060407

Copy DOI

Abstract

An engineering foundation is developed in this manuscript to allow the rational design of enzymatic transesterifications integrated with organic–organic pervaporation for the removal of methanol. In the first part, enzyme kinetics are elucidated for the solventless transesterification of two monoterpene alcohols with methyl acetate catalyzed by Novozym 435. Nonlinear regression revealed that three parameters (enzyme loading, forward and backward second-order reaction rate) sufficed to describe the entire conversion as a function of time. In the second part, a mathematical model for acetate ester production, integrated with organic–organic pervaporation, was developed based on a set of ordinary differential equations. To this end, empirical formulae for the pervaporation performance (of a PERVAP 2255-30 membrane and a standard HybSi® membrane) were established, relating methyl acetate and methanol flux to the methanol concentration in the reactor. The resulting digital twin, “PervApp”, allows us to study the influence of the key design parameters “enzyme loading” and “membrane surface” on, e.g., catalyst productivity. Finally, a techno-economic assessment is made for an annual production of 100 tons of geranyl acetate. The described methodology allows producers to shift from laborious, expensive and often disappointing trial-and-error approaches to the rational design of such integrated units.

Highlights

Lipase catalysis has the edge over conventional catalysis in several cases where sensitive substrates are used [1]
As chemical equilibria are involved in both lipase and conventional catalysis, the completion ofesterification requires an excess of a reagent and/or the continuous removal of byproducts
Amathematical mathematical model based on ordinary differential equations

Summary

Introduction

Lipase catalysis has the edge over conventional catalysis in several cases where sensitive substrates are used [1]. As chemical equilibria are involved in both lipase and conventional catalysis, the completion of (trans)esterification requires an excess of a reagent and/or the continuous removal of byproducts (e.g., by using reactive distillation [2], molecular sieves [1], bubble reactors [3] or pervaporation [4]). Continuous reactive distillation was elegantly demonstrated on the pilot-scale for butyl butyrate production in 2017 [5]. Pervaporation is an appealing technology as well, in cases where azeotropic mixtures are involved, and is potentially a less energy consuming technology compared to reactive distillation [6,7]. To the best of our knowledge, large-scale industrial applications involving lipase-catalyzed (trans)esterifications integrated with pervaporation have not been implemented so far

Methods

Results

Conclusion