Ammonia → Zinc Sulfate
Reaction equation
[NH3:1].[S:2]([O-:6])([O-:5])(=[O:4])=[O:3].[Zn+2:7].[S:8](=[O:12])(=[O:11])([OH:10])[OH:9]>>[S:2]([O-:6])([O-:5])(=[O:4])=[O:3].[Zn+2:7].[S:8]([O-:12])([O-:11])(=[O:10])=[O:9].[NH4+:1].[NH4+:1]Participants
5
Procedure
A more preferred process for the direct reduction of ammonia from a waste stream includes reacting an aqueous ammonia stream with a zinc sulfate and sulfuric acid solution to produce a spent regeneration solution of zinc sulfate and ammonium sulfate and treating such solution to cause crystallization of zinc ammonium sulfate hydrate. Preferably, the crystallization is caused by concentrating the stream by removing water. Typically this is accomplished by evaporation by conventional heating, vacuum or a combination of the two. The crystallization may also be caused by reducing the temperature of the zinc sulfate/ammonium sulfate solution or by a combination of concentration and cooling.