Patent · US Expired

Process and composition for drying of gaseous hydrogen halides

US4925646A · kind A · utility

26Cited by
6References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 25, 1989
Grant dateMay 15, 1990
Priority date
Expiry dateMay 25, 2009

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01G1/06
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process for drying a gaseous hydrogen halide of the formula HX, wherein X is bromine, Chlorine, FLuorine, or iodine, to remove water impurity therefrom, in which a scavenger precursor composition is provided, including a support having associated therewith partially or fully alkylated metal alkyl compounds or pendant groups. The precursor composition is reacted with gaseous hydrogen halide to convert the metal alkyl compounds and/or pendant functional groups to the corresponding metal halide compounds and/or pendant functional groups, which in turn react with the water impurity to produce an essentially completely water-free (below 0.1 ppm) gaseous hydrogen halide effluent. The process of the invention has utility for producing high purity, anhydrous gaseous hydrogen halides for semiconductor manufacturing operations.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.