NEW MEMBRANE-BASED ELECTROLYTIC SUPPRESSOR DEVICE FOR SUPPRESSED CONDUCTIVITY DETECTION IN ION CHROMATOGRAPHY

This paper discusses the newest advancement in chemical suppression pr eceding conductivity detection. The new suppressor uses electrolysis o f deionized water to generate the required acid or base for the suppre ssion neutralization reaction and utilizes the electrical field to enh ance, through electrodialysis, the suppressor's capacity for neutraliz ation. The suppressor is able to accommodate eluents as high as 150 mM NaOH, without the need for a separate regenerant solution, by recycli ng the conductivity detector cell waste to the regenerant and electrol yzing the water in the waste stream to the required acid or base. The device is able to use deionized water as regenerant and neutralize the eluent stream to deionized water without the expected increase in res istance by employing ion exchange material in intimate contact with th e electrodes and the membranes. The current is carried with low resist ance through the ion-exchange material via ion transport from one ion- exchange site to another.