Plasma–Catalytic Ceramic Membrane Reactor for Volatile Organic Compound Control

Decomposition of a volatile organic compound (ethylene) was carried out using nonthermal plasma created in a multihole porous ceramic membrane. The ceramic membrane employed as a low pressure drop catalyst support was loaded with manganese oxide capable of removing unreacted ozone. AC-driven discharge plasma was created inside the porous ceramic membrane to produce radicals, ozone, ions, and excited molecules available for the decomposition of ethylene. As the voltage applied to the plasma reactor was increased, the electrical discharge plasma gradually developed in the radial direction, and uniform plasma was produced in the entire ceramic membrane. The effects of specific energy input, initial ethylene concentration, and manganese oxide loading on the decomposition efficiency and the formation of byproducts were examined. It was found that the use of the manganese oxide-loaded ceramic membrane efficiently removed unreacted ozone while keeping the ethylene decomposition efficiency as high as the bare ceramic membrane case achieved. In addition, partially oxidized products such as formaldehyde, acetaldehyde, and formic acid greatly decreased by manganese loading.