Patent · US Expired

Treatment of offgas from aluminum chloride production

US4209496A · kind A · utility

19Cited by
11References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 3, 1979
Grant dateJun 24, 1980
Priority date
Expiry dateMay 3, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2004/61
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A process for treatment of aluminum chloride production offgas containing Cl.sub.2, CO, CO.sub.2, HCl, COCl.sub.2, COS, SO.sub.2, N.sub.2, SiCl.sub.4 and metal chlorides by reaction with water vapor in the presence of an alumina or low iron sand catalyst to convert SiCl.sub.4 and metal chlorides to the corresponding oxides and HCl; subsequent reaction of COCl.sub.2 with water vapor in the presence of an activated carbon catalyst to form CO.sub.2 and HCl; and removal of HCl by contacting the offgas with liquid water. Reaction with steam in the presence of alumina catalyst prior to reaction with steam in the presence of an activated carbon catalyst prolongs the useful life of the activated carbon catalyst and avoids the necessity of removing SiCl.sub.4 and metal chlorides from the offgas by adsorption onto dry activated carbon prior to contacting the activated carbon catalyst with offgas.

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