Patent · US Expired

Process for purifying perfluorinated products

US6458249B2 · kind B2 · utility

5Cited by
9References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 9, 1998
Grant dateOct 1, 2002
Priority date
Expiry dateNov 9, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/80
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Nitrogen trifluoride (NF3) containing less than 10 parts-per-million molar impurities, e.g., tetrafluoromethane (PFC-14), is disclosed. Azeotropic and extractive distillation processes using entraining agents for separating NF3 and PFC-14 from each other and from mixtures with other electronics industry materials are disclosed.

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