Scrubber solutions for scrubbing flue gas often contain amines for absorbing acid gases, e.g., sulfur dioxide (SO2). 1-(2-hydroxyethyl)piperazine and 1,4- Bis(2-hydroxyethyl)piperazine from gas scrubber solutions are separated in the Metrosep Carb 2 - 150/4.0 column and then determined using pulsed amperometric detection.