Plasma-chemical reaction

Pollution control such as the reduction of nitrogen oxides, halocarbons and hydrocarbons from flue gases [37] is another important field of plasma-assisted chemistry using non-thennal plasmas. The efficiency of plasma chemical reactions can be enhanced by introducing catalysts into the plasma [38, 39]. 

The concept of macroscopic kinetics avoids the difficulties of microscopic kinetics [46, 47] This method allows a very compact description of different non-thennal plasma chemical reactors working with continuous gas flows or closed reactor systems. The state of the plasma chemical reaction is investigated, not in the active plasma zone, but... 

The direct nitridation of Si powder by a plasma chemical reaction takes place at temperatures much higher than the melting point of Si up to 6000 K... 

The firm theoretical understanding of the spectra of model molecules has been a major impetus to apply the techniques to complex, unknown solid-state structures of technological importance. Characterization of atomic composition, structure, and bonding in the surface and subsurface of practical specimens is the first step. Most studies interpret changes in the core-level spectra in terms of surface-chemical mechanisms involved in, for example, processing conditions, exposure to inert or reactive gas plasmas, chemical reactions, or aggressive service environments. 

The NOx removal process was studied experimentally in a pulsed corona discharge combined with the Ti02 photocatalytic reaction [387]. N02 was found to adsorb easily on the photocatalyst surface, whereas NO was hardly adsorbed. Addition of water vapor enhanced the N02 adsorption. It was concluded that the main role of the plasma-chemical reaction in this system is the oxidation of NO into N02. A considerable part of N02 is adsorbed on the photocatalyst surface, and is transformed to HN03 through photocatalytic reaction with OH. 

Plasma chemical reactions are characterized by a fast reaction time involving free radicals, ions and excited molecules. Since the formation of primary radicals and the subsequent radical reactions proceed very fast within usually 10 sec, which is much shorter than the gas residence time in a NTP reactor, the overall effictetKy is not influenced by gas residence time but is determined by the energy input to the NTP reactor. It is therefore important to know the energy efficiency not only for the commercial use but also for the optimization of the system. One of the important scaling parameters is the specific input energy (SIE Pdis Qr) which is defined as the ratio of energy input (Pdis) to the unit gas flow rate (Qr). 

Yoshida, H. Marui. Z. Aoyama, M, Sugiura, J. and Mizuno, A. Removal of odor gas component utilizing plasma chemical reactions promoted by the partial discharge in a ferroelectric pellet layer / Inst. Electrostat. Jpn. 1989. /3, 425-430... 

ELEMENTARY PLASMA-CHEMICAL REACTIONS OF POSITIVE IONS... 

Elementary Plasma-Chemical Reactions of Positive Ions... 

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