Abstract: Methods for separating, monitoring, identifying, and/or quantifying a plurality of ionic species in a mixture are disclosed herein. The ionic species can include a plurality of amines in an industrial fluid. The methods can include a first chromatography step, a second chromatography step, and optionally, a third chromatography step. The first chromatography step and second chromatography step can be performed simultaneously, for example in a dual channel apparatus, such that the method can be performed in less than about 24 hours. Disclosed herein are also methods for efficiently operating a refinery.