The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 31, 1979
Filed:
Jun. 30, 1977
Karl-Heinz Dorr, Mainz, DE;
Georg Daradimos, Maintal, DE;
Hugo Grimm, Frankfurt am Main, DE;
Georg Schmidt, Frankfurt am Main, DE;
Rudolf Gerken, Krefeld-Traar, DE;
Christoph Mucke, Krefeld-Bockum, DE;
Hermann Wieschen, Cologne, DE;
Metallgesellschaft Aktiengesellschaft, Frankfurt am Main, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
A process for the recovery of sulfuric acid from waste sulfuric acid containing iron sulfate and from solid iron sulfate of high water content of crystallization which consists essentially of: A. concentrating waste sulfuric acid to an acid concentration of 25-55 weight percent, based upon the suspension, by removing water therefrom; B. mixing the concentrated acid of Step A with recycled concentrated sulfuric acid obtained from Step E to form a resultant acid mixture of acid concentration of 30-65 weight percent, based upon the suspension; C. adding said solid iron sulfate of high water content of crystallization to the acid mixture of Step B thereby obtaining iron sulfate of low water content of crystallization; D. separating the iron sulfate of low water content from the resultant sulfuric acid solution of Step C; E. concentrating the separated sulfuric acid solution of Step D to an acid concentration of 45-70 weight percent, based on salt-free acid, and recycling at least a portion thereof to Step B; and F. thermally decomposing the iron sulfate from Step D to produce iron oxide and sulfur dioxide.