ZIF-67 Incorporated Sulfonated Poly (Aryl Ether Sulfone) Mixed Matrix Membranes for Pervaporation Separation of Methanol/Methyl Tert-Butyl Ether Mixture.

Mixed matrix membranes (MMMs) with nano-fillers dispersed in polymer matrix have been proposed as alternative pervaporation membrane materials. They possess both promising selectivity benefiting from the fillers and economical processing capabilities of polymers. ZIF-67 was synthesized and incorporated into the sulfonated poly (aryl ether sulfone) (SPES) matrix to prepare SPES/ZIF-67 mixed matrix membranes with different ZIF-67 mass fractions. The as-prepared membranes were used for pervaporation separation of methanol/methyl tert-butyl ether mixtures. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and laser particle size analysis results show that ZIF-67 is successfully synthesized, and the particle size is mainly between 280 nm and 400 nm. The membranes were characterized by SEM, atomic force microscope (AFM), water contact angle, thermogravimetric analysis (TGA), mechanical property testing and positron annihilation technique (PAT), sorption and swelling experiments, and the pervaporation performance was also investigated. The results reveal that ZIF-67 particles disperse uniformly in the SPES matrix. The roughness and hydrophilicity are enhanced by ZIF-67 exposed on the membrane surface. The mixed matrix membrane has good thermal stability and mechanical properties, which can meet the requirements of pervaporation operation. The introduction of ZIF-67 effectively regulates the free volume parameters of the mixed matrix membrane. With increasing ZIF-67 mass fraction, the cavity radius and free volume fraction increase gradually. When the operating temperature is 40 °C, the flow rate is 50 L·h-1 and the mass fraction of methanol in feed is 15%, the mixed matrix membrane with ZIF-67 mass fraction of 20% shows the best comprehensive pervaporation performance. The total flux and separation factor reach 0.297 kg·m-2·h-1 and 2123, respectively.

Impacts of exogenous quorum sensing signal molecule-acylated homoserine lactones (AHLs) with different addition modes on Anammox process.

Anammox was proved having the quorum sensing ability, and several acylated homoserine lactones (AHLs) signal molecules were detected in the system. In this study, the impact of exogenous N-dodecanoyl homoserine lactone (C12-HSL) with different addition modes on the nitrogen removal, key enzymes' activity, and microbial revolution were investigated in Anammox system. Results showed that once-addition of C12-HSL had no obvious impact on Anammox. Daily-addition with 40 nM slightly improved the TN removal from 71.1 % to 74.5 %, while 80 and 200 nM significantly decreased it to 62.7 % and 61.8 %, respectively. The enzyme activity of ammonia monooxygenase increased from 0.015 to 0.068, nitrite reductase increased from 0.25 to 1.23, and nitrate reductase increased from 0.05 to 0.11 µg NO2--N mg-1 Protein min-1. Arenimonas abundance showed positive correlation with TN removal while Candidatus Kuenenia was continuously suppressed. C12-HSL was beneficial for partial nitrification, and it could be adopted for regulating the nitrite production.

One-step-synthesized d-gluconic acetal-based supramolecular organogelators with effective phase-selective gelation.

Two effective and one-step-synthesized organogelators based on d-gluconic acetal derivatives have been developed to show phase-selective gelation behaviours towards aromatic solvents from their biphasic mixtures with water. The dominant factors that drive gelation have been studied using FT-IR and temperature-dependent 1H NMR spectroscopy. Particularly, gelator GAA-2 in powder form could selectively congeal toluene, benzene and o-xylene at room temperature under mild stirring. Additionally, GAA-2 could gelate the aromatic solvents within 10 min and the recovery rate of the aromatic solvents could reach about 82% under a certain condition. The benefits of wide source availability, being easy to synthesize, and recyclable performance of the gelator make GAA-2 ideal for real-world remediation of aromatic solvents.

Water-soluble lanthanide coordination polymers particles with white-light emission and color tuning.

Water-soluble polymer particles (PPs) with strong fluorescence emission were prepared from hyperbranched poly(ethylenimine) (PEI) and terpyridine-bearing aldehyde (TPy) via Schiff base reaction and self-assembly in aqueous phase. TPy/PEI PPs were then used to develop a series of luminescent lanthanide coordination polymers particles (Ln-CPPs). The optical properties of these Ln-CPPs are readily modulated over a wide spectrum in water systems. Finally, water-soluble white-emitting Ln-CPPs were achieved by controlling the lanthanide ion stoichiometry. This Ln-CPPs design approach offers a robust pathway for white-luminescent materials in water systems.

Short-term and long-term effects of Zn (II) on the microbial activity and sludge property of partial nitrification process.

Autotrophic nitrogen removal was an innovative and economical nitrogen removal technology with less oxygen and no organics consumption, in which partial nitrification (PN) is the key component. It is necessary to clear the impact of metal ions on PN since the development of industry increased their opportunity for entering into wastewater. In this study, PN process was successfully started-up in an SBR, the short-term and long-term effects of Zn (II) on microbial bioactivity and the sludge adsorption ability for Zn (II) were investigated. Results suggested that low Zn (II) were favorable for AOB bioactivity, while the long-term effect also induced NOB bioactivity. The suppression threshold of Zn (II) on AOB in short-term effect was 10mgL-1, which rose to 50mgL-1 in the long-term effect due to the self-adaption. The PN sludge presented prominent absorbability for zinc and performed a quadratic relation with the Zn (II) concentration.