Kinetic modeling of active chlorine generation by low-amperage pulsating direct current in a circulating brine solution

A kinetic model was proposed to describe the generation of active chlorine species (ACS) in circulating 3% NaCl solution subjected to the treatments of low-amperage (0.01 A) pulsating direct current (PC) as a first step towards an effective circulation electrochemical brine disinfection process with low ACS level. The model was developed based on the mass balance between the electrochemical production and evaporation loss of ACS during the process, and found to predict reasonably well the sigmoidal ACS concentration profiles. Kinetic analysis revealed that at the same amperage, ACS was generated at a lower level by PC treatment than by normal direct current (DC) treatment through lowering of the frequency of current pulse and the capacity of condenser in the pulse circuit. This implies that PC could be more useful than DC for the delicate control of ACS at an appropriately low level during circulating electrochemical brine disinfection.