Separation of cationic biocide by means of ultrafiltration process

The usefulness of ultrafiltration process for removal of quaternary ammonium compound has been assessed. Intersep Nadir membranes with a cut-off of 5 kDa made of cellulose and polyethersulfone were tested. The concentration of cationic surfactant in the feed solutions amounted to 50–3500 mg/L. It was found that polymer type affects the removal efficiency of cationic biocide. The polyethersulfone membranes allowed to remove above 63% of BAC from the feed solution of concentration equal to 100 mg/L, while for cellulose membranes the highest retention (i.e. 27%) was obtained for process with 3500 mg/L. During the tests surfactant affected on membranes’ hydraulic properties. For experiments with polyethersulfone membranes, the relative flux obtained was in the range 80-20% (depending on pollutant concentration) of distilled water flux. Cellulose membranes were less fouling susceptible. Moreover, in experiment with surfactant concentration equal to 1000 mg/L an increase in membrane permeability (comparing to distilled water flux) was pronounced