Patent ID: 7927572

Claim:
A process for treating gaseous carbon dioxide, comprising (A) providing a gaseous feed stream of carbon dioxide that also comprises NOx and sulfur dioxide, and that is at a pressure of at least 2 bar; (B) contacting NOx-rich sulfuric acid with said gaseous feed stream and with NO 2 desorbed in step (C) to strip NOx from said NOx-rich sulfuric acid and form NOx-reduced sulfuric acid and NOx-augmented gaseous carbon dioxide that comprises SO 2 and NO 2 ; (C) converting NO in said NOx-reduced sulfuric acid to NO 2 , and desorbing said NO 2 from said NOx-reduced sulfuric acid to form NOx-lean sulfuric acid and desorbed NO 2 ; and (D) controlling the amount of desorbed NO 2 contacted with NOx-rich sulfuric acid in step (B) by converting desorbed NO 2 to nitric acid and NO, and recovering said nitric acid.