An experimental and mechanistic study on the destruction of Volatile Organic Compounds (VOCs: Methane, Methyl Chloride, Chlorobenzene, Toluene, Methyl Ethyl Ketone, 1-Pentene and Cyclohexene) in 0.21: 0.79 oxygen-nitrogen mixture “zero air” over the concentration range of 5-100000 ppm by dielectric barrier corona discharge plasma was performed. Tubular-flow, coaxial-wire, AC-powered dielectric barrier corona discharge reactors were used to determine the kinetics of destruction, reaction products and electric power requirements. High efficiency VOC destruction/removal was demonstrated. Efficiency of destruction (calculated per unit volume of air) increases with decreasing VOC concentration. At low VOC concentrations (5-100 ppm) the energy required for destruction is 0.001- 0.1 J cm

Supercritical carbon dioxide was used as a solvent to produce polymeric films on fused silica plates and metal (Al, Mg) powders. Two polymers, poly(vinylidene fluoride) and poly(4-vinylbiphenyl) (PVB), were used. Polymer-coated particles of metal powders exhibit enhanced resistance to the dissolution in aqueous basic and acidic solutions. The protective properties of the films were quantified based on the dissolution rate. The average thickness of the PVB films (that contain aromatic rings) was evaluated using UV absorption spectroscopy. A technique to measure the solubilities of poorly soluble polymers in supercritical carbon dioxide was developed. The effect of the coating conditions on the protective properties of the produced polymeric films was evaluated.

The kinetics of the reaction of maleic anhydride and isoprene in supercritical carbon dioxide was studied over an extended concentration range, from 5 × 10 -5 to 1.3 × 10 -2 mole fractions of both maleic anhydride and isoprene at 60 °C and pressure 100 atm. The apparent rate constant of the reaction was found to be concentration dependent, in contradiction with the literature data. The results are interpreted in terms of limited solubility of maleic anhydride in supercritical CO 2 . The solubility of maleic anhydride in supercritical carbon dioxide was directly measured by sampling and analyzing the supercritical phase. The observed sharp increase in the apparent rate constant of the reaction between maleic anhydride and isoprene correlates with the solubility of maleic anhydride in supercritical carbon dioxide. The interpretation was confirmed using visual observations of the phase behavior. The rate constant of the reaction measured under the true supercritical, single phase, conditions is k x ) (17.0 ( 1.3) hr -1 (mole fraction units, 60 °C, pressure 100 atm).

No abstract

No abstract