Search

The removal of acetone and benzene series (BTEX) under individual and concurrent conditions is carried out in a coaxial nonthermal plasma (NTP) reactor. The results show that the benzene series has a significant negative impact on acetone conversion and CO2 selectivity under NTP treatment. Furthermore, it is found that p-xylene significantly promotes COx selectivity under co-treatment with acetone because of greater CO generation. Based on the results of transient FTIR, MS, and GC-MS, it is seen that quantities of formic acid, formaldehyde, and ring-opening byproducts from benzene series decomposition are reduced, while quantities of aromatic byproducts with carboxyl, phenolic, and aldehyde groups on the benzene ring increase under coexistence conditions. With the help of theoretical calculation and kinetic analysis, hydrogen abstraction from the methyl group and active hydroxyl radical consumption are proposed as critical factors in the BTEX inhibition effect on acetone degradation.

A coaxial nonthermal plasma (NTP) reactor was used for the removal of nitric oxide in mist. The effects of discharge gap, thorn number, tooth slice number as well as discharge polarity on NO oxidation and NOx removal were investigated. Decreasing the discharge gap is favorable for the NO oxidation and NOx removal. The mist is almost captured completely even under a relative low input energy. Increasing the thorn number of discharge slice or tooth slice number facilitates the energy input in the plasma reactor and thus enhances the NO oxidation and NOx removal under a fixed applied voltage. The energy efficiency for the positive DC (4.5 g NO/kWh) is three times as much as that for the negative DC (1.5 g NO/kWh), corresponding to NO oxidation efficiency of around 80%. [ABSTRACT FROM AUTHOR]

The simultaneous removal of nitrogen oxides (NOx) and sulfur dioxide (SO2) by absorption is considered to be one of the most promising technologies for flue gas treatment, and sulfite is the main component of the absorption solution. To understand the chemical behaviors of the NO2 absorption in sulfite solution, the absorption time dependences of concentrations of nitrogen and sulfur compositions in both gas phase and liquid phases were investigated by flue gas analyzer, Ion chromatography (IC), Gas chromatography (GC), and Fourier transform infrared spectrometry (FTIR) methods using a bubbling reactor. The mass equilibrium of the N and S compositions were also studied. The results indicate that sulfite concentration plays a vital role in NO2 absorption. The main absorption products are NO3- and NO2 -, and NO2 -can be converted into NO3- in the presence of oxygen. Besides, about 4% to 9% by-products of S compositions are formed, and 4% to 11% by-products of N compositions such as NO, N2, N2O5, N2O, and HNO3 in the gas phase were detected in the emissions from the bubbling reactor. On the basis of N and S compositions, a possible pathway of NO2 absorption in sulfite solution was proposed. [ABSTRACT FROM AUTHOR]