Organic solvent nanofiltration (OSN) is an emerging membrane separation technology, which urgently requires robust, easily processed, OSN membranes possessing high permeance and small ...solutes‐selectivity to facilitate enhanced industrial uptake. Herein, we describe the use of two 2,2′‐biphenol (BIPOL) derivatives to fabricate hyper‐crosslinked, microporous polymer nanofilms through IP. Ultra‐thin, defect‐free polyesteramide/polyester nanofilms (≈5 nm) could be obtained readily due to the relatively large molecular size and ionized nature of the BIPOL monomers retarding the rate of the IP. The enhanced microporosity arises from the hyper‐crosslinked network structure and monomer rigidity. Specifically, the amino‐BIPOL/PAN membrane exhibits extraordinary permselectivity performances with molecular weight cut‐off as low as 233 Da and MeOH permeance of ≈13 LMH/bar. Precise separation of small dye mixtures with similar M.W. based on both their charge and molecular size are achieved.
Ultra‐thin microporous polymer composite membranes with extraordinary perm‐selectivity for organic solvent nanofiltration were fabricated by employing two novel 2,2′‐biphenol (BIPOL) derivatives as IP monomers. The enhanced microporosity arises from the hyper‐crosslinked network structure and monomer rigidity. Moreover, it can achieve precise separation of organic molecules with similar molecular weights on their charge and molecular size.
•Membrane surface modification with imidazole derivative compounds were achieved.•Imidazole derivatives were grafted onto PA membrane via surface amination with TMC.•Electrostatic repulsion was ...neutralized while size sieving obstruction was strengthened.•Solute-solute separation toward nutrient recovery and micropollutant removal was achieved.•High water permeance and excellent antifouling/anti-biofouling properties were obtained.
Domestic wastewater (DWW) contains a reservoir of nutrients, such as nitrogen, potassium, and phosphorus; however, emerging micropollutants (EMPs) hinder its applications in resource recovery. In this study, a novel class of nanofiltration (NF) membranes was developed; it enabled the efficient removal of harmful EMP constituents while preserving valuable nutrients in the permeate. Neutral (IM-N) and positively charged (IM-P) imidazole derivative compounds have been used to chemically functionalize pristine polyamide (PA) membranes to synchronously inhibit the hydrolysis of residual acyl chloride and promote their amination. Owing to their distinct properties, these IM modifiers can custom-build the membrane physicochemical properties and structures to benefit the NF process in DWW treatment. The electroneutral NF membrane exhibited ultrahigh solute-solute selectivity by minimizing the Donnan effects on ion penetration (K, N, and P ions rejection < 25%) while imposing remarkable size-sieving obstruction against EMPs (rejection ratio > 91%). Moreover, the hydrophilic IM-modifier synergistically led to enhanced water permeance of 9.2 L m−2 h−1 bar−1, reaching a 2-fold higher magnitude than that of the pristine PA membrane, along with excellent antifouling/antibacterial fouling properties. This study may provide a paradigm shift in membrane technology to convert wastewater streams into valuable water and nutrient resources.
Display omitted
Organic solvent nanofiltration (OSN) is an emerging membrane separation technology, which urgently requires robust, easily processed, OSN membranes possessing high permeance and small ...solutes‐selectivity to facilitate enhanced industrial uptake. Herein, we describe the use of two 2,2′‐biphenol (BIPOL) derivatives to fabricate hyper‐crosslinked, microporous polymer nanofilms through IP. Ultra‐thin, defect‐free polyesteramide/polyester nanofilms (≈5 nm) could be obtained readily due to the relatively large molecular size and ionized nature of the BIPOL monomers retarding the rate of the IP. The enhanced microporosity arises from the hyper‐crosslinked network structure and monomer rigidity. Specifically, the amino‐BIPOL/PAN membrane exhibits extraordinary permselectivity performances with molecular weight cut‐off as low as 233 Da and MeOH permeance of ≈13 LMH/bar. Precise separation of small dye mixtures with similar M.W. based on both their charge and molecular size are achieved.
Ultra‐thin microporous polymer composite membranes with extraordinary perm‐selectivity for organic solvent nanofiltration were fabricated by employing two novel 2,2′‐biphenol (BIPOL) derivatives as IP monomers. The enhanced microporosity arises from the hyper‐crosslinked network structure and monomer rigidity. Moreover, it can achieve precise separation of organic molecules with similar molecular weights on their charge and molecular size.
For the enhancement of pigment production by red beet hairy roots, the effects of medium constituents on hairy root cultures were investigated in flasks. In a series of cultures using media with ...diluted medium components, it was found that phosphate was a key nutrient involved in pigment accumulation in the hairy roots, and that higher pigment contents in the roots were obtained at lower phosphate concentrations. In an 18 d batch culture using phosphate-free medium, the total amount of pigment production was 4.8 times than obtained in a control culture using normal MS medium with 1.25 mol/cubic meter phosphate.
