Microfluidic Liquid-Liquid Extraction Chip with Integrated Spectroscopic Sensors

Nuclear power is the most environmentally benign way to produce electricity on a large scale. The successful use of nuclear power, however, is dependent upon adequate and safe processing and disposal of spent nuclear fuels. An important feature of nuclear energy is that spent fuels can be reprocessed to recover fissile and fertile materials and then used as fresh fuel for nuclear power plants. In nuclear fuel reprocessing system, centrifugal contactors are used as liquid-liquid extraction devices where two immiscible liquids are mixed at high speeds using a rotor, which creates a fine dispersion of droplets of organic phase in an aqueous phase that contains the analyte. Understanding the extraction efficiency at these contactors through modeling and simulation is important in the development of reprocessing technologies and the optimization of current technologies. A microfluidic flow cell extraction chip with embedded spectroscopic sensors for the analysis of analytes is being developed. The SpectraChip™ sensor will be useful in the optimization of new fuel reprocessing schemes and existing reprocessing processes by providing a microfluidic modeling platform and sensing platform to optimize extraction parameters. The Phase I work developed an MFC chip with integrated Raman and absorption fiber optic probes, demonstrated that the sensors accurately predicts the concentration of analytes by chemometric analysis and demonstrated the feasibility of using Raman and absorption measurements to detect analytes that partition into the aqueous and organic phases in a flowing system in real time. Phase II will develop an MFC chip with embedded Raman and absorption sensors, develop a field deployable SpectraChip™ sensor module, develop the chemometric model for analyte prediction, develop a rapid acquisition and chemometric modeling software, and demonstrate that the SpectraChip™ sensor yieldsextraction parameters that can optimize the extraction process. Commercial applications and other benefits: The SpectraChip™ sensor can be used in drug discovery where it could be used in the purification and detection of analytes. The SpectraChip™ sensor can be used as detectors for separation techniques such as HPLC and capillary zone electrophoresis. These techniques are widely used in the pharmaceutical, environmental, chemical and petrochemical industries.