Electrochemical acidification of Kraft black liquor: Impacts of pulsed electric field application on bipolar membrane colloidal fouling and process intensification

A comparison between the experimental results obtained from four pause lapses (6, 12, 18 and 24 s) with a pulse lapse of 6 s and a DC current indicated that application of a rigorous selected pulse/pause ratio can limit the growth of the colloidal particle, suppress the fouling on the bipolar membrane and intensify the EDBM process. The pulse/pause ratio of 6(s)/24(s) was found to be the most appropriate ratio which yielded a high current efficiency (≃80%), a low global system resistance and relative energy consumption (2.6Wh/g−NaOH) and a final pH value of 9.7 which would facilitate an efficient lignin extraction process.