(170b) Visualizing Large-Scale Biological Conversion Processes in Real-Time

The volumetric mass transfer coefficient of gas molecules is one of critical factors when designing and scaling up gas-liquid reactors as well as improving the efficiency of gas conversion. This is typically done by chromatographic techniques. For example, sampling a gas molecule of interest from the headspace of the gas-liquid reactor and subsequent gas chromatography measurement with Henry’s constants allows us to estimate the amount of the gas molecule such as carbon monoxide dissolving in water. However, this sampling-based method for determining the volumetric mass transfer coefficient is only limited to the gas-liquid reactors with relatively large gas and liquid volumes. In this talk, I will report how to precisely determine volumetric mass transfer coefficient (kLa) of carbon monoxide (CO) in miniaturized gas-liquid reactors via sensitive probing of the Raman transitions of aqueous trace CO without sampling. Then, I will briefly discuss our recent efforts to visualize biological conversion processes that take place in large-scale bioreactors in real-time. I am confident that our proposed method has a huge impact on biological conversions ranging from design and scale-up of gas-liquid reactors, process monitoring and optimization to high-throughput screening of strains or catalysts.