Fouling Prevention Using Plasma Catalysis 1999-01-3641
Atmospheric pressure nonthermal plasmas packed with a catalyst are applied to decomposition of toxic and hazardous materials in flowing gas streams for building heating, ventilation, and air conditioning (HVAC) systems. We have conducted several experiments wherein the gas phase corona reactor (GPCR) process avoids catalyst-poisoning problems. Cyanogen chloride was passed through a GPCR and a thermal reactor packed with the same three-way automobile catalyst operated at similar conditions including temperature, catalyst volume, and contaminant challenges. Within two hours, the typical breakthrough curve was observed. Large amounts of cyanogen chloride were soon found in the thermal catalyst reactor effluent revealing poisoning. In contrast, the GPCR was operated for over 100 hours without poisoning the catalyst. Other experiments are described. A mechanism that explains this catalyst preservation suggests that the application of a plasma could transport particulate from the bed in automotive applications.