Brief description of the recovery of products sulfurs of value on the basis of sulphuric acid out of print and novel products thus obtained

摘要

Improvement in the method for recovering sulfur values in the form of sulfur dioxide from spent sulfuric acid by decomposing the spent sulfuric acid at elevated temperature in the presence of elemental sulfur to generate a sulfur dioxide-containing gas stream, which involves: (a) introducing the spent sulfuric acid into a pool of molten sulfur maintained at temperature of at least about 250 C. to thereby generate a gaseous stream comprising sulfur dioxide, vaporous elemental sulfur, and water; (b) cooling said gaseous stream to temperature above the melting point of the sulfur but below about 160 C. to condense elemental sulfur therefrom, separating the condensed elemental sulfur and returning it to the pool of molten sulfur; followed by (c) further cooling the gaseous stream from which elemental sulfur has been condensed to condense water therefrom, and separating the condensed water from the gaseous stream.