Volatile organic compounds' (VOCs) effluents, which come from many industries, are triggering serious environmental problems. As an emerging technology, non-thermal plasma (NTP) technology is a potential technology for VOCs emission control. NTP coupled with F-TiO2/γ-Al2O3 is used for toluene removal from a gaseous influent at normal temperature and atmospheric pressure. NTP is generated by dielectric barrier discharge, and F-TiO2/γ-Al2O3 can be prepared by sol-gel method in the laboratory. In the experiment, the different packed materials were packed into the plasma reactor, including γ-Al2O3, TiO2/γ-Al2O3 and F-TiO2/γ-Al2O3. Through a series of characterization methods such as X-ray diffraction, scanning electronic microscopy and Brunner-Emmet-Teller measurements, the results show that the particle size distribution of F-TiO2 is relatively smaller than that of TiO2, and the pore distribution of F-TiO2 is more uniformly distributed than that of TiO2. The relationships among toluene removal efficiency, reactor input energy density, and the equivalent capacitances of air gap and dielectric barrier layer were investigated. The results show that the synergistic technology NTP with F-TiO2/γ-Al2O3 resulted in greater enhancement of toluene removal efficiency and energy efficiency. Especially, when packing with F-TiO2/γ-Al2O3 in NTP reactor, toluene removal efficiency reaches 99% and higher. Based on the data analysis of Fourier Transform Infrared Spectroscopy, the experimental results showed that NTP reactor packed with F-TiO2/γ-Al2O3 resulted in a better inhibition for by-products formation effectively in the gas exhaust.

Plasma technology has some shortcomings, such as higher energy consumption and byproducts produced in the reaction process. However non-thermal plasma associated with catalyst can resolve these problems. So this kind of technology was paid more and more attention to treat waste gas. In this paper, we make use of this technology to decompose toluene under different electric field and packed materials. At the same time, the mechanism of toluene decomposition using plasma and catalyst is discussed. The experimental results show toluene decomposition increases with electric field strength increasing and flow velocity and initial concentration decreasing. There are four conditions in plasma: without packed materials (1); with packed materials (2); with BaTiO3 in the surfaces of packed materials (3); and with nanometer Ba 0.8 Sr 0.2 Zr 0.1 Ti 0.9 O 3 (4). Toluene decomposition represents a obvious trend, that is, η(4) > η(3) > η(2) > η(1). The best decomposition efficiency of toluene arrives at 95%.

A new insight into self-support ray polarization (SSRP) of nonthermal plasma for benzene hydrocarbon decomposition in fuel exhaust was put forward. A wire-tube dielectric barrier discharge (DBD) AC plasma reactor was used at atmospheric pressure and room temperature. The catalyst was made of nano-TiO2and ceramic raschig rings. Nano-TiO2was prepared as an active component by ourselves in the laboratory. Ceramic raschig rings were selected for catalyst support materials. Then, the catalyst was packed into nonthermal plasma (NTP) reactor. Six aspects, benzene initial concentration, gas flux, electric field strength, removal efficiency, ozone output, and CO2selectivity on benzene removal efficiency, were investigated. The results showed SSRP can effectively enhance benzene removal efficiency. The removal efficiency of benzene was up to 99% at electric field strength of 12 kV/cm. At the same time, SSRP decreases ozone yield and shows a better selectivity of CO2than the single technology of nonthermal plasma. The final products were mostly CO, CO2, and H2O. Our research will lay the foundation for SSRP industrial application in the future.