The influence of an applied electric field during ceramic ultrafiltration of post-electrodeposition rinse wastewater

Electro-ultrafiltration is a method that can be employed for treating wastewater containing charged particles. In this method, an electric field produced by an applied voltage influences the movement and electrophoretic mobility of the charged particles - minimizing concentration polarization and improving permeate flux. The present study has evaluated the influence of an electric field on the filtration performance of a 50-nm ceramic ultrafiltration membrane with respect to model wastewater containing 5% v/v suspension of CED paint. Results showed that the influence of an electric field during electro-ultrafiltration of the model wastewater was dependent on both the applied voltage and transmembrane pressure (TMP). At a TMP of 100 kPa, the application of different magnitudes of voltages generally improved filtration efficiency - with the most significant improvement obtained at an applied voltage of 60 V. At an applied voltage of 60 V and TMP of 100 kPa, flux rates obtained after 60 min were higher than the flux rates obtained from ultrafiltration alone. In contrast, at higher TMPs of 200 and 300 kPa, no improvement in filtration efficiency was obtained at all magnitudes of applied voltages. (C) 2012 Elsevier Ltd. All rights reserved.