Patent · US Expired

Recovery of sulfur dioxide from gas mixtures

US3980760A · kind A · utility

2Cited by
8References
32Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 3, 1974
Grant dateSep 14, 1976
Priority date
Expiry dateSep 3, 1994

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D53/507
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Ammonia is added to combined aqueous scrubbing solutions containing an organic base-sulfuric acid reaction product, preferably an aromatic amine-sulfuric acid reaction product, an organic base-sulfurous acid reaction product, preferably an aromatic amine-sulfurous acid reaction product, and water in one or more separating zones located exteriorly of an absorption tower. The combined aqueous scrubbing solutions are obtained from sulfurous acid and sulfuric acid solution scrubbing sections of the absorption tower wherein an organic base, preferably an aromatic amine, is utilized as absorbent in a lower absorber section of the tower to remove SO.sub.2 from a SO.sub.2 -containing gas mixture, followed by scrubbing the SO.sub.2 -depleted, aromatic amine-enriched gas from the absorber section first with sulfurous acid solution in the sulfurous acid scrubbing section of the tower to remove most of the gaseous aromatic amine therefrom and then with dilute sulfuric acid solution in the sulfuric acid scrubbing section of the tower, to remove a major portion of the residual gaseous aromatic amine from the gas. Liquid sulfuric acid solution containing a relatively high concentration of aromati…

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