Abstract: In some examples, an article may include a carbon-carbon composite, an antioxidant in pores in a surface of the carbon-carbon composite, and a hydrophobic coating on the surface. The hydrophobic coating includes an oxide of a metal. The metal has a Pauling electronegativity of less than about 1.7. In some examples, the article may be a carbon-carbon composite brake disk that includes a carbon-carbon composite substrate defining a friction surface and a non-friction surface. The antioxidant may be a phosphate-based antioxidant, and the antioxidant may be in pores in the non-friction surface. In some examples, the hydrophobic coating is on the non-friction surface over the phosphate-based antioxidant. In some examples, the hydrophobic coating may include a majority of at least one of yttrium oxide, scandium oxide, or zirconium oxide.

Abstract: In some examples, an article may include a carbon-carbon composite, an antioxidant in pores in a surface of the carbon-carbon composite, and a hydrophobic coating on the surface. The hydrophobic coating includes an oxide of a metal. The metal has a Pauling electronegativity of less than about 1.7. In some examples, the article may be a carbon-carbon composite brake disk that includes a carbon-carbon composite substrate defining a friction surface and a non-friction surface. The antioxidant may be a phosphate-based antioxidant, and the antioxidant may be in pores in the non-friction surface. In some examples, the hydrophobic coating is on the non-friction surface over the phosphate-based antioxidant. In some examples, the hydrophobic coating may include a majority of at least one of yttrium oxide, scandium oxide, or zirconium oxide.

Abstract: In the synthesis of 1,1,1,3,3-pentafluorobutane (R-365mfc), a mixture of R-365mfc and the impurity 1,1,1,3-tetrafluoro-2-butene (R-1354mzy) is purified and R-1354mzy is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1354mzy in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture. The R-1354mzy is reduced to below 10 wt. ppm as it is converted to 2,3-dichloro-1,1,1,3-tetrafluorobutane (R-354) or other butane containing more chlorine and having a higher boiling point than R-365mfc. The butane(s) may be separated more easily from R-365mfc. The photochlorination is effected in a manner such that at least about 96 weight percent of the starting amount of R-365mfc is maintained in the mixture.

Abstract: A gas adsorbent system includes a molded gas adsorbent within a housing. The molded gas adsorbent is disposed in the housing so that shifting is prevented without adhering the gas adsorbent to the housing, for example, by completely filling the housing. The gas adsorbent may include activated zeolite 13X. The gas adsorbent may be formed from a polymer solution such as polysulfone, and contain an organic binder.

Abstract: In the synthesis of 1,1,1,3,3-pentafluorobutane (R-365mfc), a mixture of R-365mfc and the impurity 1-chloro-3,3,3-trifluoropropene (R-1354zd) is purified and R-1354zd is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1354zd in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture. The R-1354zd is reduced to below 10 wt. ppm as it is converted to 2,3-dichloro-1,1,1,3-tetrafluorobutane (R-354) or other butane containing more chlorine and having a higher boiling point than R-365mfc. The butane(s) may be separated more easily from R-365mfc. The photochlorination is effected in a manner such that at least about 96 weight percent of the starting amount of R-365mfc is maintained in the mixture.

Abstract: A method of making a gas adsorbent comprises dissolving a polymer in one or more first solvents to form a polymer solution; mixing an inorganic adsorbent with the polymer solution to form a precursor; molding the precursor; and leaching the first solvents from the precursor with a second solvent.

Abstract: A gas adsorbent is made by dissolving a polymer in one or more first solvents to form a polymer solution; mixing an inorganic adsorbent with the polymer solution to form a precursor; molding the precursor; and leaching the first solvents from the precursor with a second solvent.

Abstract: In the synthesis of 1,1,1,3,3-pentafluorobutane (R-365mfc), a mixture of R-365mfc and the impurity 1-chloro-3,3,3-trifluoropropene (R-1354zd) is purified and R-1354zd is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1354zd in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture. The R-1354zd is reduced to below 10 wt. ppm as it is converted to 2,3-dichloro-1,1,1,3-tetrafluorobutane (R-354) or other butane containing more chlorine and having a higher boiling point than R-365mfc. The butane(s) may be separated more easily from R-365mfc. The photochlorination is effected in a manner such that at least about 96 weight percent of the starting amount of R-365mfc is maintained in the mixture.

Abstract: A titania bound ion exchange composition is prepared by admixing crystalline sodium titanate and a hydrolyzable titanium compound and then drying the titania bound crystalline sodium titanate. The dried titania bound ion exchange composition is subjected to optional compaction and calcination steps to improve the physical strength of the titania bound composition.

Abstract: A chemically modified mica composite formed by heating a trioctahedral mica in an aqueous solution of sodium chloride having a concentration of at least 1 mole/liter at a temperature greater than 180 degrees Centigrade for at least 20 hours, thereby replacing exchangeable ions in the mica with sodium. Formation is accomplished at temperatures and pressures which are easily accessed by industrial equipment. The reagent employed is inexpensive and non-hazardous, and generates a precipitate which is readily separated from the modified mica.

Abstract: In the synthesis of 1,1,1,3,3-pentafluoropropane (R-245fa), a mixture of R-245fa and the impurity 1-chloro-3,3,3-trifluoropropene (R-1233zd) is purified and R-1233zd is removed from the mixture by contacting the mixture with 1-5 mols of chlorine for each mol of R-1233zd in the presence of ultraviolet light having a wavelength between about 300 to 400 nm which provides at least 0.02 watts-hour/kg of the mixture, the R-1233zd being reduced to below 10 wt. ppm or lower, as it is converted to 1,2,2-trichloro-3,3,3-trifluoropropane (R-233) or other propane which contains more chlorine and which has a higher boiling point than R-245fa and can be separated easily from R-245fa, the photochlorination being effected in a manner such that at least about 96 wt. % of the starting amount of R-245fa is maintained in the mixture.

Abstract: This invention is method for preparing a titania bound ion exchange composition comprising admixing crystalline sodium titanate and a hydrolyzable titanium compound and, thereafter drying the titania bound crystalline sodium titanate and subjecting the dried titania bound ion exchange composition to optional compaction and calcination steps to improve the physical strength of the titania bound composition.

Abstract: The present invention relates to a process for recovering sulfur hexafluoride ("SF.sub.6 "). More specifically, the invention provides a pressure swing adsorption--desorption process for recovering SF.sub.6 from a gas stream using zeolites, activated carbons, or silicalites to adsorb the SF.sub.6.