Biomimetic dynamic membrane for aquatic dye removal. (15th March 2019)

• Record Type: Journal Article
• Authors: Chen, Wensong; Mo, Jiahao; Du, Xing; Zhang, Zhien; Zhang, Wenxiang
• Is Part Of: Water research. Volume 151(2019)
• Page Start: 243
• Page End: 251
• Publication Date: 2019-03-15
• Subjects: Biomimetic dynamic membrane (BDM) -- Adsorptive dynamic membrane (ADM) -- Dye removal -- Enzymatic degradation -- Adsorption; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2018.11.078
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: This study utilized physical adsorption and filtration of carbon nanotubes (CNTs) and laccases to fabricate biomimetic dynamic membrane (BDM) for the advanced treatment of dye wastewater. In BDM, the adsorption, enzymatic degradation and membrane separation demonstrated a synergism effect on pollutant removal. At first, the fabrication methods of BDM were investigated, and the mixed filtration for laccases and CNTs showed a better performance than the stepwise filtration. Furthermore, the operation parameters of BDM, including CNTs and laccase loading amounts, dye concentration, agitation speed and transmembrane pressure (TMP), were studied. Suitable CNTs and laccase amounts could reduce filtration resistance and increase catalysis efficiency, while moderate TMP and agitation speed were in favor of boosting the BDM structure for catalysis and permeability. Optimized operation parameters (CNT loading amount = 20 g m −2, laccase loading amount = 74.6 g m −2, agitation speed = 100 rpm, and TMP = 1.0 bar) sustained a high removal rate, and the flux was over 120 L m −2 h −1, even for 7 operation cycle' tests. BDM exhibited an excellent dye removal rate, stable flux and great antifouling capacity, on the ground that adsorption saturation and foulant may be alleviated "online and in-situ" by the enzymatic degradation. Afterwards, the bionic layer on BDM, after absorption saturation and catalyst deactivation, could be eliminated rapidly by carrying out a simple backwash cleaning operation, then a new one could be fabricated immediately. Therefore, BDM is a good candidate for functional membrane materials in future water treatment. Graphical abstract: Image 1 Highlights: BDM was fabricated by physical adsorption and forward filtration of laccase and CNTs. Adsorption, enzymatic degradation and membrane separation had a synergism effect. Mixed filtration was more conductive for BDM fabrication than stepwise filtration. Backwash could rapidly remove the inactive BDM and refabricate a new one. BDM had high removal rate and great flux (over 120 L m −2 h −1 ) for 7 cycle' tests.