Working up spent sulphuric acid simultaneously with sulphate salts

US4153628A · kind A · utility

Assignees

• BAYER HEALTHCARE LLC · DE
• Metallgesellschaft AG · DE

Inventors

• Rudolf Gerken · Krefeld, DE
• Hans Guth · Leverkusen, DE
• Christoph Mucke · Krefeld, DE
• Willi Potes · Neunburg vorm Wald, DE
• Hermann Wieschen

Key dates

• Filing date: Sep 26, 1977
• Grant date: May 8, 1979
• Expiry date: Sep 26, 1997

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S423/02
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Spent sulphuric acid, either alongside or mixed with contaminated metal salts such as iron sulphate heptahydrate, is regenerated to fresh acid by countercurrent contact with gases from cleavage of the sulphate salts, such gases containing SO.sub.3 which effects build up of the acid concentration. The built up acid is evaporated in another stage to obtain pure acid. The metal sulphate solids are subjected to high temperature cleavage, generating SO.sub.3 which effects the previous concentration. Cleavage also produces some SO.sub.2 which is converted to SO.sub.3 by wet catalysis.