We are interested in designing continuous-flow reactors for catalytic reactions, which require intensified transport phenomena. The examples include multiphase and photocatalytic reactions. Flow chemistry presents a paradigm shift for conducting multiphase reactions as it creates a large interfacial area between phases. Our effort has been to develop flow systems (rotating bed, spinning-disk, and packed-bed reactors) for a biphasic liquid-liquid esterification reaction and an oxygen-dependent enzymatic reaction. We are employing flow chemistry to transform the way we approach photochemical reactions. We have utilized flow reactors with short light paths to enhance photon transfer to reagents and photocatalysts. We are also engaged in developing transport phenomenon modeling to elucidate interactions between reagents and heterogeneous catalysts as they flow through the reactor.

Selected publications: 

• React. Chem. Eng., 2019, 4(2), 235-243

• J. Env. Chem. Eng., 2023, 11(5), 111010

• Ind. Eng. Chem. Res., 2022, 61(3), 1322-133

We use reaction engineering principles, including kinetics modeling and dimensional analysis, in order to design an efficient biocatalytic process. Our key strategies encompass flow biocatalysis and bioprocess-separation integration. The flow biocatalysis development is to address key challenges in most bioprocesses such as a low gas diffusion rate and a difficult bioprocess scale-up. Moreover, our research has explored new hybrid separation-bioprocess systems such as an extractive bioconversion, which significantly increases a production yield due to an in-situ removal of inhibitory products. We have undertaken a comprehensive analysis of in-situ and in-line separations. We used a semi-empirical approach to simulate the continuous hydrogen fermentation integrated with continuous in-line liquid-liquid extraction and to evaluate the process for its feasibility. Our on-going progress also involves a bioprocess simulation to perform techno-economic and life-cycle assessments in order to evaluate each bioprocess as well as benchmark it against a conventional chemical method.

Selected publications: 

• React. Chem. Eng., 2021, 6(10), 1771-1790

• React. Chem. Eng., 2022, 7(2), 310-318

• React. Chem. Eng., 2023, 8(10), 2387-2402

• Biores. Tech. Reports., 2023, 101651

• ACS Sustain. Chem. Eng., 2022, 10(45), 14724-14734

We also have made significant progress on in-line purification tools that facilitate integration of multi-step flow synthesis. The scheme allows for continuous synthesis without any batchwise separation between reaction steps. In particular, we are interested in creating new continuous extraction tools such as membrane-based liquid-liquid separations and dynamic-flow pressurized extractions (Unpublished work). We have developed analytic models to understand membrane-based separations. We have demonstrated use of the membrane-based separators for continuous extractions. Recently, we also aim to create new solid-liquid extraction techniques (e.g., dynamic-flow pressurized solvent extraction) for applications in recovery of essential compounds in plant materials.

Selected publications: 

• J. Flow. Chem., 2020, 10, 353-362

• Chem. Eur. J., 2018, 24(11), 2776-2784 

• ACS Med. Chem. Lett., 2020, 11(1), 9-15

• Ind. Eng. Chem. Res., 2017, 56(14), 4095-4103 

• Ind. Eng. Chem. Res., 2017, 56(42), 12184-12191 

• React. Chem. Eng., 2019, 4(2), 235-243