I. E. Filatov

Nickel nitride synthesized by nitrogen ion beam sputtering of a nickel target

The sputtering of a nickel target with a beam of nitrogen ions is accompanied by the formation of crystalline nickel nitride (Ni3N), which is deposited on cold surfaces surrounding the target. A special feature of this synthesis is the low temperature of the process and the formation of this single form of nickel nitride. The products were studied using electron probe microanalysis, X-ray diffraction, and magnetic measurements.

Cleaning air from multicomponent impurities of volatile organic compounds by pulsed corona discharge

The relative efficiency of the removal of impurities from airflow under the action of pulsed corona discharge has been studied by processing model mixtures of air with volatile organic compounds (VOCs). A method is proposed that allows the influence of the VOC structure on its reactivity to be directly determined. For this purpose, it is suggested to calculate a relative energy parameter characterizing the reactivity of a given impurity component in the framework of the method employed. This approach significantly intensifies the process of determination of the energy parameters of impurity removal and can be used as a criterion for comparative estimation of the efficiency of various methods employing nonequilibrium plasma for cleaning air from VOCs.

Processes of carbon disulfide degradation under the action of a pulsed corona discharge

Experiments on decomposition of carbon disulfide CS2 in air under the action of a pulsed nanosecond corona discharge have been carried out. The energetic efficiency of the degradation amounted to 290–340 g (kW h)–1, which is significantly higher than with the use of a corona discharge at a constant voltage. The main degradation products are sulfur dioxide SO2, carbonyl sulfide COS, sulfuric acid, and carbon dioxide. Processes occurring in pulsed corona discharge plasma and leading to carbon disulfide degradation are considered. Different methods of air purification from carbon disulfide are compared.

Macrokinetic description of the elimination of volatile organic impurities from gases using plasmachemical methods

We present a mathematical model describing the elimination of volatile organic impurities from gases by plasmachemical methods and formulate criteria for the purification of a medium from an impurity. Comparison of the developed theory to experimental data on the styrene conversion in ionized air shows adequacy of the description. Using the proposed model, it is possible to generalize data obtained for the gas mixtures of various compositions with allowance for the method of activation employed in each particular case. A change in the reaction order with respect to the eliminated component is demonstrated. The obtained relations provide a basis for the development of effective methods of eliminating toxic compounds from waste gases.

Elimination of styrene vapor from air by a pulsed electron beam

Styrene vapor contained in air in small amounts is decomposed when the air is subjected to a pulsed electron beam and non-self-maintained space discharge. The physical laws of the process and the final products of styrene vapor conversion are found. Experimental data make it possible to consistently describe the styrene vapor elimination from air exposed to a pulsed electron beam and relate the beam parameters to the properties of the gas flow being irradiated.

Streamer corona removes styrene vapor from air flow

Decomposition of the styrene vapor in air induced by a 60-ns pulsed streamer corona discharge was studied. Empirical relationships were obtained that allow the necessary energy consumption to be evaluated depending on the required degree of purification, the initial styrene content in air, and the nitrogen-oxygen mixture composition. On this basis, a general equation is derived that provides systematization of the experience in air purification.

Styrene vapor decomposition in air under the action of a pulsed electron beam

The results of experiments on the removal of styrene vapors from air with the aid of nanosecond electron beam pulses and a non-self-sustained volume discharge are reported. The macrokinetic equations based on these results allow the experimental data to be systematized and extrapolated beyond the range of vapor concentrations and deposited energies studied.

The removal of volatile organic compounds from air by pulsed electron beams

Many organic synthesis processes are accompanied by ventilation emissions of exhaust air contaminated with the vapor of volatile organic compounds (VOCs). Recent investigations have shown the efficiency of using electron beams to remove the vapor of VOCs from exhaust air. The use of pulsed electron beams for these purposes has not been, adequately explored yet. The goal of the present work was to study the processes of removal of VOCs from the air by means of a 3-ns electron beam. Subjects of inquiry included acrolein, styrene and benzene, i.e., the most common toxic VOCs present in emissions by various enterprises, synthesizing organic compounds, producing plastic materials, etc.

Estimation of Qualitative and Quantitative Parameters of Air Cleaning by a Pulsed Corona Discharge Using Multicomponent Standard Mixtures

The efficiency of removal of volatile organic impurities in air by a pulsed corona discharge is investigated using model mixtures. Based on the method of competing reactions, an approach to estimating the qualitative and quantitative parameters of the employed electrophysical technique is proposed. The concept of the “toluene coefficient” characterizing the relative reactivity of a component as compared to toluene is introduced. It is proposed that the energy efficiency of the electrophysical method be estimated using the concept of diversified yield of the removal process. Such an approach makes it possible to substantially intensify the determination of energy parameters of removal of impurities and can also serve as a criterion for estimating the effectiveness of various methods in which a nonequilibrium plasma is used for air cleaning from volatile impurities.

The Catalytic Effect of Electronegative Additives on Removal of Perchloroethylene Vapor from Air by Pulsed Corona Discharge

It is established that electronegative additives (CCl4, freon-113) produce a catalytic effect on the conversion of volatile organic compounds (VOCs) under the action of atmospheric-pressure nonequilibrium plasma generated in pulsed corona discharge. At concentrations below 0.1%, these additives significantly decrease the discharge current, but the energy efficiency of the process of VOC removal from air increases. The catalytic effect of electronegative additives on the VOC conversion in air and nitrogen is quantitatively demonstrated in the case of perchloroethylene C2Cl4 (PCE) vapor removal. The addition of 0.085% CCl4 to air reduces the energy consumption for PCE removal at initial concentration of 0.09% by half (from 12 to 6 eV per molecule) at a 63% degree of cleaning. Mechanisms explaining the active inf luence of electronegative additives on the discharge current and the process of impurity removal are suggested.