Toward Ideal VOCs and Nanoparticle Emission Control Technology Using a Wet-Type Catalysis Nonthermal Plasma Reactor

Abstract

Several exhaust gas regulations are being implemented to prevent the hazardous emissions of volatile organic compounds (VOCs) and particulate matter (PM) from paint and print factories. The VOCs generate photochemical oxidants and suspended PM, such as PM _2.5 , which has become a global environmental problem. We evaluate the catalytic nonthermal plasma (NTP) technique for controlling the emission of VOCs. The article proposes a wet-type catalysis plasma reactor to extend the treatment of water-soluble VOCs. Initial evaluation of the proposed technique involves simultaneous removal of nanoparticles along with individual VOCs, toluene, acetaldehyde, acetic acid, and ammonia, at a relatively high gas flow rate of 10 L/min. Further, pellets of α -alumina and TiO ₂ spheres are employed in the NTP reactors for assessing their catalytic performance. We install an MnO ₂ catalytic reactor downstream of the plasma reactor for ozone removal. Simultaneous treatment of typical VOCs and nanoparticles using dry and wet-type catalytic NTP reactors shows that the wet-type reactor has superior average particle collection efficiency of 100%. However, the dry-type NTP with α -alumina shows a higher toluene removal efficiency of 91% compared to 73% in the wet type. Further, the respective removal efficiencies for acetaldehyde, acetic acid, and ammonia are 100%, 100%, and 95%. Notably, the toluene removal efficiency drops to 65% with the TiO ₂ catalyst.