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[Display omitted] • Imprinted membranes with bilayer-mesoporous structure were successfully fabricated. • A shell@void@core@void@shell pathway was constructed for acteoside separation. • Imprinted membrane is used to selectively separate acteoside from natural products. • Imprinted membranes had high rebinding capacity and permselectivity for acteoside. The main active component of Cistanche tubulosa is acteoside (ACT), which is difficult to separate due to its low content. Therefore, it is important to develop an efficient method for efficient separation of ACT. Herein, the ACT-based molecularly imprinted nanocomposite membranes (A-MINMs) doped with bilayer-mesoporous carbon nanospheres (BMCNs) were fabricated for efficient separation of ACT. The designed BMCNs mixed with polyvinylidene fluoride (PVDF) powders to prepare the hybrid membranes (BMCNs@PVDF) by a phase inversion method. Then, a sol–gel method was used to synthesize the ACT-imprinted layer on the BMCNs@PVDF. The A-MINMs-400 synthesized under the given conditions demonstrated an excellent rebinding capacity of 114.94 mg/g, the brilliant permselectivity of 7.15, and the rebinding selectivity of 4.48. It mainly attributed to the following three reasons: (i) The designed BMCNs possessed a well-defined bilayer-mesoporous structure composed of the mesoporous carbon shell, interlayer void, and mesoporous carbon core. This bilayer-mesoporous structure can construct the efficient shell@void@core@void@shell pathways in A-MINMs for intercepting ACT molecules through the A-MINMs. (ii) The interlayer void structure can provide a large space for accommodating ACT molecules, thereby enhancing the rebinding capacities of A-MINMs. (iii) The introduced BMCNs nanofillers facilitated to form the abundant ACT-imprinted sites and cavities, improving the selectivity of A-MINMs for ACT. Therefore, the development and design of A-MINMs with bilayer-mesoporous nanofillers had a great potential for efficient separation of bioactive active constituents from natural products. [ABSTRACT FROM AUTHOR]

• Organic solvent NF membranes were prepared using 4,4′-diaminodiphenylmethane. • Hydrophobic-modified NF membrane had the optimal performance in THF. • The permeances of organic solvents are related to the specific solvent properties. A kind of thin film composite polyamide nanofiltration (NF) membrane was synthesized via the interfacial polymerization between a new diamine monomer of 4,4′-diaminodiphenylmethane and trimesoyl chloride on the surface of cross-linked polyetherimide, and evaluated in some organic solvents including ACN, MeOH, EtOH, THF, etc. The optimal organic solvent NF membrane was selected to prepare respectively the hydrophilic membrane (Phi-NF) via grafting of Tris and the hydrophobic membrane (Pho-NF) via grafting of 2,2,2-trifluoroethylamine, combining with the characterization of ATR-FTIR, XPS, SEM, 13C NMR, AFM, etc. The permeance values of Phi-NF and Pho-NF membranes change greatly with organic solvents. Pho-NF-2 possesses the highest permeance of 66.4 L m−2 h−1 MPa−1 in THF with the erythrosin B (EB) rejection of 99.5%. Through analyzing the physiochemical properties of the organic solvents and calculating the surface energy, the correlations are deduced for the synthesized membranes, illustrating that the permeances of organic solvents are roughly proportional to the specific solvent properties for Phi-NF-2 and Pho-NF-2. The results suggest one promising method to enhance the separation performance of organic solvent NF membranes. [ABSTRACT FROM AUTHOR]

Graphical abstract Organic solvent NF membranes prepared via IP between BTC and amine terminals on co-crosslinked PEI show stable permeance and rejection in DMF solutions. Highlights • EDA-XDA co-crosslinked polyetherimide (C-PEI) has excellent organic solvent resistance. • NF membranes are synthesized via interfacial polymerization between BTC and the amine terminals on C-PEI. • The modified NF membrane has the DMF permeance of 6.1 L m−2 h−1 MPa−1 and the RB rejection about 89%. Abstract A co-crosslinked poly(ether imide) (PEI) material with excellent organic solvent resistance was synthesized using mixed amines of aliphatic ethylenediamine (EDA) and aromatic p-xylylenediamine (XDA), on which the organic solvent nanofiltration (NF) membrane was prepared via the interfacial polymerization between the monomer 1,2,4,5-benzene tetracarbonyl chloride (BTC) and the amine terminals on the co-crosslinked PEI. Structural characterizations indicate that the EDA-XDA co-crosslinking is an effective pathway to modulate the species and the amount of amine terminals on the surfaces, which can in turn affect the toplayer thickness and the surface roughness of the synthesized NF membrane. The results illustrate that the NF membrane prepared on the EDA-XDA (1:1) co-crosslinked PEI (c-P/1E1X) possesses superior separation performance and stability for N,N-dimethylformamide (DMF) solution. Further, the superior solvent resistant NF membrane gly-NF-c-P/1E1X-XDA was synthesized through an additional quick patching-like IP using XDA, with the aid of ethylene glycol filling inside the intermediate pores. The membrane gly-NF-c-P/1E1X-XDA shows the DMF permeance of 6.1 L m−2 h−1 MPa−1 and the Rose Bengal (RB) rejection about 89%, and for a 5 g/L ceftazidime antibiotic DMF solution, the permeance is 4.6 L m−2 h−1 MPa−1 and the ceftazidime rejection is 81%, which is promising to be applied for the recovery of heat sensitivity ceftazidime in DMF solution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of solid particles on liquid–liquid extraction were revealed. • Impacts of rotor structures of high shear mixer on extraction were assessed. • Equipment performance is highly related to vortex and turbulent characteristics. • Machine learning algorithms were used for prediction of mass transfer coefficient. The liquid–liquid extraction process with solid particles is of practical importance in the chemical industry. Consequently, the inline high shear mixer (HSM) was employed for the process intensification, and the effects of particle size and concentration, rotor revolution speeds, and rotor structural parameters were revealed in this work. Results indicate that increasing the rotor revolution speed remarkably promotes mass transfer performance. The extraction efficiency (E) and mass transfer coefficient (K L a) increase at low revolution speeds, yet mainly decrease with the elevated particle concentration. The larger particle size is more unfavorable to mass transfer. E and K L a first decline and then increase with the raised rotor outer diameter, and more rotor teeth correspond to higher E and K L a. Increasing the forward teeth angle promotes liquid–liquid extraction. The relationship between K L a and key parameters is established via machine learning algorithms with high accuracy for HSM design and optimization. [ABSTRACT FROM AUTHOR]

Ammonium lignosulfonate (AL), a cheap lignin derivative with abundant phenolic building block structures, was first used as the monomer to synthesize a thin film composite nanofiltration (NF) membrane via interfacial polymerization with trimesoyl chloride (TMC) on the cross-linked poly(ether imide) substrate. The AL-TMC NF membranes show superior organic solvent resistance, the optimal NF-2AL membrane has a permeance of 0.97 L m −2  h −1  MPa −1 and a 98% rejection for Brilliant Blue R-250 (BB, 825 g mol −1 ) in DMSO. To enhance the permeance further, we adopted vanillic alcohol (VA), which possesses a molecular structure similar to the subunit of AL, to synthesize a VA-TMC NF membrane. Combining with characterizations of ATR-FTIR, 13 C NMR, XPS, SEM and AFM, etc., it is illustrated that the VA-TMC NF membrane is composed of polyarylester and exhibits high DMSO permeance about 21 L m −2  h −1  MPa −1 , the comparable BB rejection of 89% and a rejection of 81% for clindamycin phosphate. These results suggest a promising route to select potential monomers to synthesize desirable nanofiltration membrane with superior antisolvent property and separation performance. [ABSTRACT FROM AUTHOR]

For efficient recovery of lithium from brines, a composite nanofiltration (NF) membrane with positively charged skin layer (PA-B) was first synthesized via interfacial polymerization between branched poly(ethylene imine) (BPEI) and trimesoyl chloride (TMC) on the support of crosslinked polyetherimide, and the separation performance was assessed for simulative brine of mixed LiCl/MgCl 2 solution. To improve the permselectivity of Li + against Mg 2+ , then we adopted EDTA to modify the as-prepared positively charged PA-B NF membrane. The optimal EDTA modified NF membrane PA-B2-E3 showed the separation factor S Li , Mg about 9.2 for the LiCl/MgCl 2 mixed solution with a Mg 2+ /Li + mass ratio of 24, with excellent stability within 36 h filtration, which would have promising applications in the recovery of Li from brine. [ABSTRACT FROM AUTHOR]

To explore an economic Fluoride-adsorbent with high capacity and superior selectivity as well as easy regeneration, a new synthetic strategy was constructed through a hydrothermal procedure with the aid of glucose to prepare high performance adsorbent ZrO 2 -MgO@C composite (CZMC). The adsorption capacity and the selectivity toward fluorine ions were evaluated for the synthesized adsorbents. Through characterizations of XRD, BET, SEM, HRTEM, XPS, etc., the crystal structure, the morphology and the chemical composition of the adsorbents were analyzed, illustrating that CZMC has the desirable structure with high dispersion of metal oxides in the porous carbonized microspheres. The results indicate that ZrO 2 -MgO@C composite show the F-ions adsorption capacity of 184.5 mg/g, with excellent resistance toward disturbance of other anions including NO 3 −, Cl−, SO 4 2−, CO 3 2− and PO 4 3−. DFT calculations show that the adsorption process of fluorine ions occurs spontaneously and accompanied by orbital hybridization of surface atoms. Such composite adsorbent having high adsorption capacity and superior F-selectivity as well as the feature of easy regeneration would possess promising applications in the treatment of waste water containing fluorine ions. • ZrO 2 -MgO@C was investigated for fluoride treatment. • Surface reaction is explored by DFT analysis. • Electrostatic attraction, ion exchange, and surface complexation are adsorption mechanisms. • Theoretical adsorption capacity was 184.5 mg/g. • The adsorbent has good regeneration performance and practical application value. [ABSTRACT FROM AUTHOR]

• Poly (butyl acrylamide-co-divinylbenzene) nanofiltration membrane was synthesized. • The toplayer regularly distributed oxygen and nitrogen groups to anchor metal ions. • Fe-binding treatment enhanced the permeance and dye rejection in organic solvents. • Changes of the void size and the charge density in the toplayer were disclosed. A new nanofiltration composite membrane poly (butyl acrylamide-co-divinylbenzene) (poly-TaDb) was synthesized via a facile photopolymerization on polyetherimide using the monomers of n- tert -butyl acrylamide and divinylbenzene, and evaluated the separation performance in organic solutions. The unique poly-TaDb toplayer has a feature of branch structure containing regularly distributed oxygen and nitrogen groups that work as the interacting sites with metal ions (Fe3+, Zn2+, and Cu2+), as reflected by the characterizations of ATR-FTIR, XPS, AFM, etc. Without the metal ion treatment, the optimal poly-TaDb membrane shows the permeance of 31, 17, 20.4 L m−2h−1 MPa−1 respectively for organic solutions of tetrahydrofuran (THF), methanol (MeOH) and acetonitrile (ACN), with the rejection rates higher than 90% toward EB dye (879.8 g.mol−1). After interacting with these metal ions, the obtained Fe-binding poly-TaDb membranes possess higher permeance, with the THF, MeOH, and ACN permeance enhanced respectively to 113, 35, and 24.2 L m−2h−1 MPa−1, meanwhile maintaining high dye rejection rate. While the Cu- and Zn-binding membranes show much higher permeance but lower dye rejection rate. Density functional theory (DFT) calculations disclose that the void size of the toplayer network increases in the order of: the pristine (11.40 Å) < Fe-binding (11.54 Å) < Zn-binding (11.60 Å) < Cu-binding membrane (11.63 Å). It is the suitable void size and charge density distribution in the toplayer network of Fe-binding membrane. that results in the superior nanofiltration performance. This work provides a facile route to explore new polymeric network materials for highly effective separation performance in organic solvents. [ABSTRACT FROM AUTHOR]

Abstract: Bovine serum albumin (BSA) anchored on the surface of magnetic Fe3O4 nanoparticles (MNPs) were prepared using electrostatic adsorption and studied as a new magnetically chiral selector for the separation of chiral drug enantiomers. It is indicated that the immobilized BSA molecules on the magnetic nanoparticles using electrostatic adsorption retain their stereoselective recognition with site II-binding drug ibuprofen at pH 7.0 and site I-binding drug ofloxacin at pH 9.0, with a optimal loading of 467mg BSA per gram of MNPs. For racemic ibuprofen and ofloxacin, single-stage adsorption gives an enantiomeric excess of 13% and 14%, and the multi-stage operation enhances the chiral performance providing the ee value of 54% and 39% respectively. As increasing the initial ee of enantiomeric mixtures, Δee levels of 50%, 35% and 16% for stronger binder ibuprofen, as well as 31%, 17% and 13% for weaker binder ofloxacin are achieved under the same operational conditions. Depending upon the eutectic point of racemic compound, a hybrid process involving the enrichment of one enantiomer using BSA–PDDA–MNPs followed by subsequent crystallization is proposed to obtain the enantiomer with higher optical purity. [Copyright &y& Elsevier]

• A novel poly[acrylate-co-amide] membrane was synthesized via the photopolymerization. • The UV-cured membrane showed excellent solvents resistance. • Molecular simulations reflected the dependence between voids and organic solvents. • The optimal membrane had good separation performance in THF solution. A novel poly[acrylate-co-amide] network composite nanofiltration membrane was synthesized via the photopolymerization on the top of amine-terminated polyetherimide using the photoinitiator BP and the monomers of TPGDA and PETA, of which the void size in the toplayer network can be modulated via a solvent immersion. The synthesized UV-15T2P-11 network membrane showed the permeance of 7.1 L m−2 h−1 MPa−1 and SBB rejection of 95% in THF. Then, molecular simulations suggested that DMF immersion can make the void size in the membrane toplayer increased from the pristine 1.0 nm to 1.7 nm. DMF-activated membrane p-UV-15T2P-11 shows excellent performance and long-term stability, with the permeance of 13.2 L m−2 h−1 MPa−1 and the SBB rejection of 91% in THF. These results illustrate that the photopolymerized network polymers combined with solvent activation are promising materials to manufacture organic solvent nanofiltration membranes. [ABSTRACT FROM AUTHOR]

• An IL-based heterogeneous structure nanofiller ([Hmim][NTf 2 @LDHN) was designed. • IL@LDHN was prepared by impregnating LDHN into a [Hmim][NTf 2 methanol solution. • The [Hmim][NTf 2 @LDHN was used to fabricate MMMs. • The cooperation of [Hmim][NTf 2 and LDHN facilitates CO 2 transport. • The resulting MMMs exhibit superior CO 2 /CH 4 separation performance. An ionic liquid-decorated layered double hydroxide nanocage ([Hmim][NTf 2 @LDHN) was designed and incorporated into Pebax matrix to fabricate high-performance MMMs for CO 2 separation. The [Hmim][NTf 2 on the external surface, interlamellar spacing, and internal hollow core of LDHN plays cooperative roles with LDHN for improving CO 2 permselectivity. First, the [Hmim][NTf 2 on the external surface of LDHN absorbs more CO 2 molecules than CH 4 , improving CO 2 /CH 4 selectivity. Then, the captured CO 2 permeates into LDHN shells and are dissolved by [Hmim][NTf 2 in the interlamellar spacing of LDNH. The dissolved CO 2 combines quickly with CO 3 2− carriers existed in LDHN itself, accelerating CO 2 transport. Third, the [Hmim][NTf 2 encapsulated in the internal hollow core of the LDHN has an ultrahigh CO 2 capacity, which increases both CO 2 permeability and selectivity. The cooperation of [Hmim][NTf 2 and LDHN significantly enhances CO 2 separation performance. In particular, under humidified conditions the Pebax/[Hmim][NTf 2 @LDHN-6 MMM presents optimal separation performance with a CO 2 permeability of 644 ± 25 Barrer and a CO 2 /CH 4 separation factor of 34 ± 0.53, which transcends the upper bound relationship developed by Robeson (2008). The nanofillers combining ILs with nanocages exhibit a promising prospect to fabricate high-performance MMMs for gas separations. [ABSTRACT FROM AUTHOR]