(308b) Heterogeneous Interfaces Confined in Microreactors and Characterized By in situ Spectroscopic Techniques

Engineering novel tools for the discovery of science and translation of the new knowledge from the laboratory to application are societal challenges. In this work, we help address these challenges by applying microreaction engineering principles with in situ Raman and UV-vis spectroscopy and microscopy. Engineering online analytics with continuous-flow microsystems has the potential to reduce the amount of chemical waste generated, minimize the building space and energy requirements, expedite information, yield more accurate predictive mathematical models, and enable safer handling of hazardous compounds during scientific discovery, development, and manufacture. This so called “process intensification” has merit to revolutionize the way we currently discover, develop, and manufacture useful materials and compounds.

This presentation will summarize three examples of why microflow reactors with in situ analytics can advance society. Confined gas-liquid and liquid-liquid interfaces behave differently than unconfined ones created in traditional chemical manufacturing processes. Using in situ Raman spectroscopy, the role of tangential fluid motion at static confined methane-water and aqueous-nonpolar interfaces will be reported. Remarkably, the interfaces are made up of layers that influence molecular transport. In our second example, we have begun to examine the influence of the Al₂O₃:SiO₂ ratio (an important characteristic of hydrocarbon reservoir mineralogy) on asphaltenes damage in quartz packed-bed microreactors using in situ Raman spectroscopy, UV-vis spectroscopy, and pressure sensors. Hydrocarbon reservoirs are complex in their mineralogy and chemistry. The outcomes of stimulation chemistry on asphaltenes-damaged reservoirs are not yet well understood, due to a lack of available information in the field and limited laboratory techniques for the discovery of asphaltenes-reservoir interactions. Microfluidics offer an effective platform for rapid, in situ characterizations at experimental conditions that simulate sandstone reservoirs. In our third example, cryogenic flash crystallizations are often difficult to control, and therefore understanding mixed-heat-transfer-limited and crystallization-limited kinetics can be an arduous endeavour in the laboratory. By in situ Raman spectroscopy and microscopy, we have discovered the transition from heat-transfer-limited to crystallization-limited kinetics of methane (sI) hydrates. Our findings could help understand strategies for natural gas storage, flow assurance in hydrocarbon and natural gas production, and the continuous manufacture of nanomaterials. Finally, a few emerging trends in catalysis and reaction engineering will be highlighted.