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[Display omitted] • A core–shell QQ-encapsulated structure was prepared by a standardized method. • SIPN shell enables excellent biocontainment with physical and chemical stability. • The anti-biofouling and phosphorus removal were enhanced in QQ microcapsule MBR. • QQ microcapsule promoted the application of QQ media for anti-biofouling in MBR. Microbial quorum quenching (QQ) has been proven to be a sustainable anti-biological fouling strategy for membrane bioreactors (MBR), but the long-term stability and practical application in MBR were uncertain. We reported a novel semi-interpenetrating network (SIPN) hydrogels-based design of QQ bacteria (Rhodococcus sp. BH4) encapsulation for both biofouling control and enhancement of organic pollutants removal in MBR. The microcapsule included the alginate core, chitosan thin intermediate compartment and SIPN (sodium alginate / polyacrylamide) shell, which exhibited near-perfect biocontainment, including preventing detectable QQ bacteria escape and improving mechanical strength. The QQ-microcapsules in the MBR demonstrated its significant anti-biofouling effect for treating synthetic wastewater (i.e., membrane fouling was delayed by 233%-280% compared to the control MBR membrane). Meanwhile, the efficiency of phosphorus removal was developed in QQ-microcapsule MBR because of the enhanced phosphorus removal triggered by the flocculation of polyacrylamide (PAM) fraction in SIPN. This promising QQ media brings the broad potential for biofouling control and long-term efficient operation in actual MBR wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • The BH4 immobilized media were prepared using nano-silica and silica beads as core reinforcements. • The inclusion of two types of silicon in the beads ensured they were ready for prolonged use. • The application of two quorum quenching media effectively mitigated MBR biofouling. Quorum quenching (QQ) is a strategy to alleviate membrane biofouling in membrane bioreactors (MBRs). As a stable inorganic material with a large specific surface area, silica is often used to prepare of microbial immobilization composites. This study selected two different sizes of silica materials (silica beads and Nano-silica) to make the core encapsulate a QQ bacterial strain (Rhodococcus sp. BH4). The compressive strength and stability under extreme environments were characterized, and the positive effect of silica on QQ beads was verified. The results showed that both QQ beads could resist the impact of high pressure, acid, alkali, salt and EDTA buffer. It was proved that they have the potential to quench effectively continuously. Both beads were still more than 70 % QQ activity after five months of use. In the lab-scale continuous MBR experiment, the time of transmembrane pressure (TMP) reaching 50 kPa in both experimental groups was more than 3 times that in the blank group. The TMP contamination time was extended from 5 to 6 days in the blank group to 18–19 days. Among them, silica beads greatly improve the compressive strength of the beads, and also have a better performance in QQ. [ABSTRACT FROM AUTHOR]