Counter-Currently Operated Reactive Extractor with Additively Manufactured Enzyme Carrier Structure

The development of continuous flow reactors for heterogeneous chemical or biochemical reactions raises the question of efficient mixing and catalyst immobilization. Especially, in those cases where hybrid reactor concepts are aimed at, combining of reaction and extraction in one apparatus requires a solution for reaction and extraction phase distribution and immobilization concepts. Precisely designed structures inserted as reactor packings can be used to control the multiphase hydrodynamics and to act as a catalyst carrier simultaneously. However, the decision for the most suitable structure for specific reaction systems remains a challenge. While numerical simulations with computational fluid dynamics (CFD) has limitations regarding the complex interactions in multiphase flows, performing experiments using rapid prototyping (RP) offers the possibility of a fast fabrication and verification of tailor-made structures for specific flow characteristics, efficient mass transport and high conversion rates. Additionally, RP can be used to quickly approve results from CFD simulations in experiments. In the presented work the development of a counter-currently (CC) operated additively manufactured reactor (AMR) for the decarboxylation of ferulic acid (FA) to 2-metoxy-4-vinylphenol (MVP) along in situ extraction with n-heptane is shown. Here, the use and optimization of periodic open-cell structures (POCS) as a carrier for the enzyme phenolic acid decarboxylase and a distributor for the extraction phase is targeted. By rapid prototyping of transparent structures and their examination with respect to the induced flow characteristics of colored heptane, a structure could be optimized for the specific reaction system. The additive manufacturing of the POCS and its application in a CC AMR enabled 95% conversion of 5 mM FA in two hours and a MVP concentration in reaction phase below 0.5 mM.