Abstract: Polysilazane/polysiloxane block copolymers particularly suitable for the preparation of durable, adherent silicon-containing coatings comprising polymeric segments of a polysilazane and polysiloxane are disclosed.

Abstract: Polysilazane/polysiloxane block copolymers particularly suitable for the preparation of durable, adherent silicon-containing coatings comprising polymeric segments of a polysilazane and polysiloxane are disclosed.

Abstract: This invention is directed to novel ammonolysis products including novel silazanes and polysilazanes characterized by repeating units of silicon-nitrogen in a polymeric compound having a reduced amount of Si—H bonds relative to the amount of Si—H bonds in the starting compound. Preparation of these novel ammonolysis products comprises introducing a starting compound containing at least one Si—H bond, such as a halosilane into a stoichiometric excess of anhydrous liquid ammonia wherein an ammonium halide is generated acting as an acid catalyst to provide an ionic and/or acidic environment for preparing the novel ammonolysis compounds. The prepared novel ammonolysis products are retained in a separate liquid-phase layer and distinct from the anhydrous liquid ammonia containing the ionized ammonium halide. Also provided are methods to purify ammonolysis products and to modify ammonolysis products by controllably increasing viscosity from a liquid to a solid and viscosities there between.

Abstract: Energetic materials, such as nitrocellulose, TNT, RDX, and combinations thereof, optionally in combination with chemical warfare agents, such as mustard gas, Lewisite, Tabun, Sarin, Toman, VX, and combinations thereof, are destroyed when chemically reacted according to the method of the invention. The method comprises reacting the energetic materials and chemical warfare agents, of present, with solvated electrons which are preferably produced by dissolving an active metal such as sodium in a nitrogenous base such as anhydrous liquid ammonia.

Abstract: Chemical warfare agents, including vesicants and nerve agents distributed throughout the world, are destroyed when chemically reacted according to the method and utilizing the apparatus of this invention. The method comprises reacting the chemical warfare agents with nitrogenous base, optionally containing solvated electrons which are conveniently produced by dissolving an active metal like sodium in a nitrogenous base such as anhydrous liquid ammonia.

Abstract: Refrigerants, such as Freon.RTM. 12 and other potential ozone depleting substances will be in short supply as their production is phased out, and until existing refrigeration equipment is retrofitted to receive more environmentally friendly refrigerants. Existing supplies of such refrigerants when contaminated with other refrigerants especially hydrofluoroalkanes like Freon 22 can form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with aqueous solutions of metal hydroxides or other bases. The remaining non-reacted refrigerant-containing composition is readily recycled by separation and recovery methods from the reaction mixture to provide a reusable refrigerant composition virtually free of contaminating refrigerant.

Abstract: Solid and liquid substrates, such as soil and solvents having radioactive metals or hazardous non-radioactive metals are decontaminated with the aid of cyanide ion generated in-situ to form co-ordination compounds with the unwanted metal contaminants. Cyanides are prepared by introducing into an ammoniacal liquid-containing slurry of a contaminated soil, or other solid or liquid substrate, a refrigerant compound, such as a hydrochlorofluorocarbon which produces ammonium cyanide, which in-turn forms a complex with the hazardous metal contaminant for separation with the ammoniacal liquid. The process may also utilize solvated electrons to at least partially dehalogenate a perhalogenated refrigerant like diclorodifluoromethane (R-12). Process avoids exposure to potentially hazardous cyanides through in-situ generation, while simultaneously destroying unwanted refrigerants which are potentially harmful to Earth's ozone layer.

Abstract: Refrigerants, such as Freon.RTM. 12 and other potential ozone depleting substances will be in short supply as their production is phased out, and until existing refrigeration equipment is retrofitted to receive more environmentally friendly refrigerants. Existing supplies of such refrigerants when contaminated with other refrigerants especially chlorofluorohydrocarbons like Freon 22 form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with bases such as metal hydroxides in aqueous solutions or compatible organic solvents. The remaining non-reacted refrigerant-containing composition is readily recycled by separation and recovery methods from the reaction mixture to provide a reusable refrigerant composition practically free of contaminating refrigerant.

Abstract: Soil including sand and clays contaminated with nuclear waste materials and/or ions of hazardous non-radioactive metals or metalloids are decontaminated by treating with anhydrous liquid ammonia alone or in combination with solvated electrons. Methods include removing ions of hazardous metals or metalloids by mixing with ammoniacal solutions to provide an ammoniacal liquid-containing product with coordination complexes. Methods also comprise concentrating contaminants, such as plutonium, uranium and thorium, for example, in the fines of soil and clay to yield residual soil products which are sufficiently free of contaminants to allow reclamation. Economics are improved over aqueous systems since ammonia can be recovered and recycled. By concentrating nuclear and nonnuclear wastes in soil fines space requirements ordinarily needed for storage of untreated soil and handling costs can be significantly reduced.

Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse. Hazardous cyanides which may develop are converted to relatively benign products during the process by introducing a base to convert volatile cyanides to more stable salts which in turn are converted to useful compounds of lesser toxicity.

Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with non-aqueous liquid nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse.

Abstract: Improved methods for purification and recovery of individual refrigerants from refrigerant mixtures without chemical destruction of the contaminating refrigerant. Aqueous solutions are employed in extraction methods by relying on differences in water solubilities and partition coefficients at ambient temperatures. All refrigerants can be recovered and the aqueous solutions reused to form a cyclic process. Methods include countercurrent extraction.

Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with non-aqueous liquid nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse.