Patent · US Expired

Method and apparatus for producing sulfur hexafluoride

US5744022A · kind A · utility

2Cited by
5References
25Claims
0Family size

Inventor

Key dates

Filing dateFeb 19, 1997
Grant dateApr 28, 1998
Priority date
Expiry dateFeb 19, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25B1/245
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

The present invention is directed to an apparatus and methods for preparing sulfur hexafluoride within an electrolytic cell by reacting elemental sulfur with fluorine electrolytically generated from substantially anhydrous hydrogen fluoride in the presence of a conductivity-enhancing solute. The reaction occurs at the anode of the electrolytic cell in a liquid electrolyte comprising substantially anhydrous hydrogen fluoride and an alkali fluoride wherein the concentration of hydrogen fluoride is maintained between about 64 and about 88 mole percent. The electrolytic cell is preferably divided into a cathodic half-cell and an anodic half-cell by a non-conductive diaphragm which permits passage of the electrolyte and current to provide communication between the half-cells while being impervious to fluid communication above the electrolyte to keep the generated gases separate. When so divided, substantially pure sulfur hexafluoride may be recovered from the space above the electrolyte in the anodic half-cell. The present apparatus and methods provide significant energy savings in the manufacture of sulfur hexafluoride.

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