Coupling of dielectric barrier discharge plasma with oxygen permeable membrane for highly efficient low-temperature permeation

Abstract

Ceramic oxygen permeable membranes (OPMs) are widely considered the “next generation” technology for pure oxygen separation and catalytic membrane reactors. However, the main issue of OPM is high operating temperature (above 800 °C) and resulting implications for materials, cost, as well as operating complexities (e.g., sealing, creep deformation, and thermal shock during thermal cycling). A new design for coupling OPM La0.6Sr0.4Co0.2Fe0.8O3-δ with a dielectric barrier discharge plasma (a type of atmospheric pressure non-thermal plasma) is proposed for highly efficient low-temperature (600 °C) oxygen permeation. This study demonstrates that the plasma can activate the surface exchange reactions. Applying 15 W air-plasma can effectively reduce the apparent activation energy of the permeation process from 136.6 to 43.1 kJ mol−1. The oxygen flux is increased by a factor of nearly 30 at 600 °C with a plasma power of 15 W. The newly developed plasma-membrane micro-reactor design enables further performance enhancement at lower operating temperatures and integration with solid oxide fuel cells, catalytic membrane reactors, and oxygen permeable membranes.