Alleviating reverse osmosis membrane fouling caused by biopolymers using pre-ozonation

Publication date: Available online 9 October 2019Source: Journal of Membrane ScienceAuthor(s): Zhonglong Yin, Tiancheng Wen, Yan Li Aimin, Li, Chao LongAbstractPre-ozonation prior to membrane filtration was widely investigated for the mitigation of membrane fouling by biopolymers, nevertheless, the application of ozone pre-treatment on reverse osmosis (RO) membrane is limited. In this work, bovine serum albumin (BSA) and sodium alginate (SA) were selected as representatives of protein and polysaccharides, respectively. RO fouling by BSA, SA and BSA + SA (weight ratio = 1:1) solutions was investigated before and after pre-ozonation with ozone dose ranging from 0.05 to 0.25 mg O3/mg DOC (dissolved organic carbon). The results showed the fouling alleviation was limited for filtration of all foulants at ozone dose of 0.05 mg O3/mg DOC. When ozone dose was higher than 0.10 mg O3/mg DOC, however, pre-ozonation effectively increased the permeate flux and decreased the irreversible fouling. The improvement of the permeate flux and reversible fouling was due to the increase in electrostatic (EL) repulsion and decrease in hydrophobic interaction between biopolymer and RO membrane, resulting from the increase in negative charge and hydrophilicity of BSA and SA after pre-ozonation. In addition, the results of in-situ streaming potential measurement showed that pre-ozonation reduced the deposition of BSA and SA on RO membrane and weakened the adhesive force between BSA (or SA) an...
Source: Journal of Membrane Science - Category: Materials Science Source Type: research