Yu. V. Titova

Investigation of the Opportunity for Increasing the Yield of Hydrogen Peroxide in Plasma-Solution Systems

The influence of the addition of alcohol (ethanol and propanol-2) to an electrolyte solution on hydrogen peroxide formation under the action of glow and gliding discharges of atmospheric pressure was studied. The addition of alcohol up to 0.1 mol/l was found to increase the yield of H2O2 significantly.

Yields of hydroxyl radicals and hydrogen peroxide in a glow discharge system with a liquid cathode

A model of the hydroxyl radical yield estimation in a glow discharge-water system is presented. The hydroxyl radical yield has been found. The initial yield of hydrogen peroxide and its effective lifetime have been calculated. The yield of hydroxyl radicals obtained by the suggested model is shown to be in good agreement with the experimental data of other investigators.

The influence of plasma-solution treatment on the properties of hemp fiber lignin

The effect of an atmospheric pressure gas discharge generated inside an electrolyte solution on hemp lignin has been investigated by the methods of IR spectroscopy. It is shown that the gas-discharge activation causes a threefold increase of the lignin solubility with the further chemical treatment. The feasible processes of the interaction of the active particles generated in the electrolyte solution under the discharge action with the lignin macromolecules are considered.

Application of Plasma-Solution Treatment for Modification of Bast Fibers

Delignification processes of rough bast fibers under the action of face discharge were studied. The residual lignin content in the fiber and the fiber mass loss were determined after the plasma-solution and subsequent short chemical treatment with reduced alkalinity. This two-stage treatment was shown to be an effective delignification method for bast fibers, since the delignification degree amounts to 68% for flax, 64% for hemp, and 39% for jute fibers.

Effect of the cathode material on the accumulation of hydrogen peroxide in a plasma-solution system

The accumulation of hydrogen peroxide in a plasma-solution system with an electrolyte cathode under glow discharge action in relation to the cathode material has been studied, as well as the kinetics of the accumulation of Cu2+, Ni2+, and Ag+ ions passing from the cathode into the solution at the discharge combustion. It is shown that the Cu2+ concentration is comparable with that of the H2O2, and the use of a silver cathode results in a considerable decrease of the initial formation rate and the highest concentration of hydrogen peroxide in the plasma-solution system under study.

Accumulation of hydrogen peroxide at the long-term effect of an atmosphere pressure glow discharge on electrolyte solutions

The kinetic characteristics of the hydrogen peroxide accumulation at the long-term effect of an atmospheric pressure glow discharge on aqueous solutions of electrolytes have been obtained. The initial rates of the H2O2 generation and the primary yields are calculated using the straight line portions of the kinetic characteristics. It is found that the times of reaching a steady hydrogen peroxide concentration (or its maximum) are rather long (about several hours). The OH· yield has been estimated, and the initial yield of hydrogen peroxide and its effective lifetime have been calculated using the kinetic relationship obtained for a glow discharge-water system.

Chemical interactions of a model lignin compound under plasma-solution treatment

Chemical transformations of isoeugenol (a model lignin compound) have been investigated under the combined action of an atmospheric pressure discharge initiated in the volume of an electrolyte and alkali treatment using UV spectrophotometric analysis. Plasma-solution activation has been shown to be an initiator of the oxidative breakdown of the aromatic structure of the compound during alkali treatment.

Effect of a gas discharge in the bulk of an electrolyte solution on its physical and chemical properties

The effect of a gas discharge at atmospheric pressure in dielectric tubes filled with an electrolyte solution on the acidity and electroconductivity of solutions of sulfuric acid, sodium hydroxide, and sodium sulfate at various concentrations has been studied. The dynamic current-voltage characteristics of the volume discharge have been obtained for a wide number of electrolytes. It is shown that such discharge action on the investigated solutions causes the growth of their pH and the decrease of their electroconductivity. The process under study is found to be periodic with the electrophysical parameters being dependent not only on the solution electroconductivity but also on its chemical composition.

Investigation of atmospheric-pressure gliding discharge action on an electrolyte solution

The effect of atmospheric-pressure gliding discharge action on an electrolyte solution was studied. The hydrogen peroxide yields in the solutions were defined after the discharge treatment, as well as the pH and electroconductivity values. Gliding discharge was shown to be more effective than glow discharge for H2O2 formation in the electrolyte solution.

Influence of gas-discharge plasma treatment in the electrolyte bulk on the cellulose properties

The effect exerted on cellulose properties by plasma-solution treatment using the atmospheric-pressure diaphragm and end discharges was examined.