Antibiofouling performance and mechanisms of a modified membrane in a membrane bioreactor: Role of silver@silica nanopollens
Antibiofouling performance and mechanisms of a modified membrane in a membrane bioreactor: Role of silver@silica nanopollens
复制标题
膜生物反应器中改性膜的防污性能和机制：银@二氧化硅纳米花粉的作用
DOI：
10.1016/j.watres.2020.115749
复制
发表时间：
2020
期刊：
影响因子：
12.8
通讯作者：
Wang Zhiwei
中科院分区：
文献类型：
--
作者：
Zhang Xingran;Guo Yu;Wang Tianlin;Wu Zhichao;Wang Zhiwei
Biofouling remains to be one of major obstacles in membrane bioreactors (MBRs), calling for the development of antibiofouling membranes. Silver nanoparticles (AgNPs), being a kind of broad spectrum bactericidal agent, have been widely used for modifying membrane; however, uncontrollable release of AgNPs and thus a short lifetime of modified membranes are thorny issues for the AgNPs-modified membranes. In this study, silica nanopollens were used as AgNPs nanocarriers for membrane modification (ASNP-M), which could improve silver delivery efficacy, avoid agglomeration and control Ag+release towards bacteria. At a silver loading of 107.7 ± 10.9 μg Ag/cm2, ASNP-M effectively inhibited growth ofEscherichia coliandStaphylococcus aureus, with an Ag+release rate of 0.5 μg/(cm2d). Long-term MBR tests showed that ASNP-M exhibited a significantly reduced transmembrane pressure increase rate of 0.88 ± 0.34 kPa/d which was much lower than that of two control membranes, i.e., pristine membrane (M0) (2.32 ± 0.86 kPa/d) and Ag@silica nanospheres (without spikes) modified membrane (ASNS-M) (2.25 ± 1.28 kPa/d). No significant adverse influences on the pollutant removal were also observed in the reactor. Foulants analysis revealed that biofilm of ASNP-M was thinner and comprised of mainly dead cells, and only organic matter with strong adhesion properties was allowed to attach onto the membrane surface. Bacterial community analysis suggested that the incorporation of Ag@silica nanopollens inhibited colonization of bacteria which are capable of causing membrane biofouling (e.g.,ProteobacteriaandActinobacteria). These findings highlight the potential of the antibiofouling membrane to be used in MBRs for wastewater treatment and reclamation.
