(255b) A Packed-Bed Dielectric Barrier Discharge Microplasmatron for Characterization of Plasma-Liquid Multiphase Flows

Micro dielectric barrier discharge plasma combines the advantages of non-thermal plasma with those of microreactors, and its potential in areas such as chemical synthesis has been explored. ^1–5 Plasma-liquid systems are attracting attention owing to their broad range of establish and promising applications. ^6,7 Microfabricated packed-bed reactors, with their enhanced mass transfer between multiple phases, enable precise on-chip temperature control and the ability to tune the porous media, e.g., void fraction, pore size, shape, and arrangement. ^8,9

Our lab has designed, fabricated, and characterized a multifunctional micro-plasmatron. The device consists of a low resistivity chromium layer deposited on top and bottom of the reactor to establish stable 3D counter-current multiphase flows. An additional high-dielectric-constant silicon layer serves as a dielectric barrier to generate homogeneous nonthermal plasma within hundreds of confined discharge gaps under atmospheric pressure. Micropillars are also implemented and are arranged in a way to serve as a porous media for the optimum 2-D mixing of components that replenish a plasma-liquid interface. Plasma excitation of methane/helium gas mixtures was pinpointed by applying an alternating high-voltage across the dielectric barrier. A dispersion model was evaluated through residence-time-distribution (RTD) measurements. The above results will be presented and discussed.

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9 S. Morais, et al., Lab Chip, 2016, 16, 3493–3502.