Buffered flue gas scrubbing system using adipic acid by-product stream

In a method for the removal of sulfur dioxide from waste combustion gases which comprises bringing the gases into interfacial contact with an aqueous solution or slurry of limestone or lime buffered by a compound or compounds which significantly increase the dissolution of limestone or lime, the improvement comprising employing as the buffer a byproduct stream which is the byproduct of the process comprising:

• (1) oxidizing cyclohexane to cyclohexanol and cyclohexanone;
• (2) oxidizing the cyclohexanol and cyclohexanone with a strong oxidizing acid into a product stream comprising adipic acid with minor amounts of glutaric and succinic acids;
• (3) crystallizing adipic acid from the product stream in one or more stages leaving said byproduct stream comprising glutaric acid, succinic acid, residual amounts of adipic acid and water, and the strong oxidizing acid.