Performance of selected anion exchange resins for the treatment of a high DOC content surface water

The MIEX® and IRA938® anionic resins exhibit a faster removal of NOM and mineral anions compared to the DOWEX11® and MSA® AERs. All the resins were found to be very effective with similar performances after 30 to 45 min of contact time. As expected, only limited sorption of atrazine and isoproturon (C0=1 μg/L) occurred with MIEX®, DOWEX11® and MSA® AERs. MIEX® resin proved to be very efficient in eliminating NOM of high-molecular weight but also a large part of the smallest UV absorbing organic compounds which were refractory to coagulation/flocculation treatment. Remaining DOC levels after 30 min of contact with MIEX® were found similar in raw water, clarified water and even post-ozonated water implying no DOC benefit can be gained by employing conventional treatment prior to MIEX® treatment. Removal of bromide (initial concentration 110 μg/L) was also observed and ranged from 30% to 65% for resin dose increasing from 2 to 8 mL/L.