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The dynamic coexistence of heterostructures is crucial for the synergistic function of molecularly imprinted polymers (MIPs) derived from high internal phase emulsions (HIPEs). In this work, hydrophilic boronate affinity imprinted hydrogel sorbents (H-UIO-66-NH2-IHIPEs) were prepared by biphasic synergistic HIPEs droplet reactors filled with reactive microencapsulation system, and used to capture and separate cis-diol containing luteolin (LTL) from complex extraction samples with high selectivity. As the main solid emulsifier, UiO-66-NH2, prototype zirconium-based metal–organic frameworks (MOFs) greatly improves the mechanical performance of the hydrogel, whilst preventing overuse of surfactants. Space-confined formation of imprinted sites in the external phase is realized in the presence of hydrophilic acrylamide phenylboric acid monomer (H-BA), which endows the specific affinity with pH responsiveness to LTL. In addition, the filled microinclusion compound containing elastic monomer octadecyl methacrylate (SMA) and functional monomer glycidyl methacrylate (GMA) simultaneously added interfacial cross-linking reaction to provide stable pore volume and pore shape. Combined with these excellent properties, H-UIO-66-NH2-IHIPEs showed fast capture kinetics (75 min) and large uptake amount (39.77 mg g−1) at 298 K, and confirmed the existence of a uniform chemisorption monolayer. Moreover, excellent recyclability of 6.24% loss in adsorption amount after five adsorption–desorption cycles was observed. Finally, the LTL content of the purified product (about 97.38%) was higher than that of the crude extract (about 85.0%). This study sheds a new light for the design of novel imprinted hydrogel sorbents combined with binary synergistic components.

Phosphorus and nitrogen flow to water leads to eutrophication and depletion of reserves. Bionic-inspired tannin modification is proposed for preparing a tannin-modified La-Zn(4,4'-dipy)(OAc)2/bacterial cellulose composite membrane for simultaneous adsorption of total phosphorus and ammonia nitrogen in water. Its physical and chemical properties were characterized by XRD, SEM, FT-IR, TGA and other characterization. La-Zn(4,4'-dipy)(OAc)2 nanomaterial achieved effective adhesion on the tannin-modified bacterial cellulose membrane. Adsorption experiments showed that the composite membrane can both adsorb total phosphorus and ammonia nitrogen, and adsorption capacity of ammonia nitrogen is better than that of total phosphorus. The maximum adsorption capacities of ammonia nitrogen and total phosphorus are 482.35 mg/g and 374.71 mg/g. In the binary solution, the adsorption capacity of the composite membrane to ammonia nitrogen and total phosphorus decreased, but the adsorption capacity to phosphorus decreased slightly. Results of adsorption experiments showed that the adsorption process of nitrogen and phosphorus by the composite membrane belongs to single-layer adsorption, and the calculation results of the kinetic equation are in accordance with the quasi-second-order, and the adsorption equilibrium of the composite membrane was reached within 360 min. In short, the composite membrane has a better adsorption and separation effect both on ammonia nitrogen and total phosphorus.

Metal–organic framework (MOF) materials are a class of hybrid organic–inorganic supramolecular materials. Owing to their highest specific surface area, lowest crystal density and adjustable pore size and functional structure, MOF materials have the potential for some special applications in the field of adsorption of heavy metal contaminants. However, it is difficult to collect and reuse them in adsorption separation because of their nanometer size. Therefore, graphene oxide (GO) with good film-forming properties is used. In this paper, an f-ZIF-8@GO composite membrane material was developed by using GO and a zeolitic imidazolate framework (ZIF-8) material and was modified with 3-aminopropyl-triethoxysilane (APTES) by amine functionalization. After a series of structural characterizations, it was applied to the adsorption of copper ions in water and its adsorption properties were tested. The results showed that the adsorption capacity at pH = 6.0 was the largest, and an increase in temperature was not conducive to the adsorption reaction. The adsorption data were fitted to the Freundlich equation and the quasi-second order kinetic equation. The adsorption of Cu2+ on water was multilayer, and the equilibrium adsorption capacity was up to 1872.24 mg g−1. The prepared materials exhibited high selectivity to copper ions; they could be reused as adsorbents for many times and maintained high adsorption capacity. This kind of material is of great significance for the adsorption and separation of heavy metal ions in water.

Phosphorus and nitrogen flow to water leads to eutrophication and depletion of reserves. Bionic-inspired tannin modification is proposed for preparing a tannin-modified La–Zn(4,4′-dipy)(OAc)2/bacterial cellulose composite membrane for simultaneous adsorption of total phosphorus and ammonia nitrogen in water. Its physical and chemical properties were characterized by XRD, SEM, FT-IR, TGA and other characterization methods. La–Zn(4,4′-dipy)(OAc)2 nanomaterial achieved effective adhesion on the tannin-modified bacterial cellulose membrane. Adsorption experiments showed that the composite membrane could both adsorb total phosphorus and ammonia nitrogen, and adsorption capacity of ammonia nitrogen was better than that of total phosphorus. The maximum adsorption capacities of ammonia nitrogen and total phosphorus were 482.35 mg/g and 374.71 mg/g. In the binary solution, the adsorption capacity of the composite membrane to ammonia nitrogen and total phosphorus decreased, but the adsorption capacity to phosphorus decreased slightly. Results of adsorption experiments showed that the adsorption process of nitrogen and phosphorus by the composite membrane belonged to single-layer adsorption, and the calculation results of the kinetic equation were in accordance with the quasi-second-order, and the adsorption equilibrium of the composite membrane was reached within 360 min. In short, the composite membrane had a better adsorption and separation effect both on ammonia nitrogen and total phosphorus.

Metal organic framework materials (MOFs) are kinds of hybrid materials with intra-molecular pores formed by self-assembly of organic ligands and metal ions through coordination bonds. In the paper, a type of MOFs named as [Zn(μ-L)(μ-1,3-dpp)](mof-1), using Zn2+ as metal ions, 4,4′-oxybis(benzoic acid) and 1,3-di(4-pyridyl)propane as organic ligands was synthesized. The rare earth element lanthanum, which has specific adsorption for phosphorus, is intercalated into mof-1 by the impregnation method in order to remove phosphorus-containing wastewater. In order to optimize the nano-sized La-mof-1 materials to facilitate separation, we prepared a membrane by blending MOFs materials with graphene oxide (GO) by pressure application. The addition of GO not only facilitates the separation of materials, but also has excellent removal ability for water purification. After a series of structural characterization, the adsorption properties of materials were tested. The experimental results showed that the total phosphorus in the water can get to the maximum adsorption capacity when pH = 4.0. It can be viewed in thermodynamic studies that increasing the temperature favors the adsorption reaction. Increasing the temperature to the 318 K, the equilibrium adsorption capacity of the membrane to total phosphorus in the water reached 139.51 mg/g. The adsorption removal rate of total phosphorus can reach 100% when its concentration is lower than 100 mg/L. This highlights the advantages of intercalating lanthanum into MOFs. The penetration curve was drawn by dynamic adsorption experiments to understand the mass transfer mechanism of La-mof-1GO membrane. Since GO also has a large specific surface area, it is another excellent adsorption material. Experimental data showed that compared with the original water sample, the removal rate of COD in the water reached 73.9%.

Low-density aerogels with three–dimensional porous structure were synthesized using soluble chitosan oligosaccharide (COS) and graphene oxide (GO) as raw materials under mild conditions. Tetraethylenepentamine was used as the crosslinker of COS and the bridge between GO and COS, as well as the provider of functional groups. Structural characterizations revealed that crosslinked COS polymers firmly fixed on the surfaces of GO sheets and abundant amino groups homogeneously distributed in the pores. The adsorption capacity of the aerogel for Cr(VI) can reach up to 519.8 mg/g, while the adsorption efficiency for trace Cr(VI) adsorption can also reach 100% especially. The adsorption mechanism was investigated with X–ray photoelectron spectroscopy and zeta potential analysis. The superb properties suggested that the strategy of using COS as a raw material for the fabrication of adsorbents with controllable structure and form is meaningful.

A kind of water-soluble chitosan, chitosan oligosaccharide, was used to synthesize a crosslinking hydrogel using a simple method, and the outstanding adsorption property of the hydrogel for Cr(VI) was investigated. The three-dimensional structure of the synthetic material was analyzed by means of 13C solid state nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) measurements. The hydrogel also exhibited high thermal stability and mechanical strength. Its adsorption capacity for Cr(VI) reached 148.1 ± 2.4 mg/g with a fast adsorption rate. Pseudo-second-order kinetic model and Langmuir isotherm well described the adsorption process. Notably, the hydrogel still showed 100% removal efficiency for Cr(VI) at low concentration (0.02–1 mg/L) in the detectable range. The simple preparation process, high mechanical strength and excellent adsorption property indicate that the hydrogel has great potential for the removal of Cr(VI) ions from water and wastewater.

Silica/cell composites were prepared for the adsorption of lead ions, Pb(II), from aqueous solution in a batch system. The silica/cell composites possessed micropores, high surface area, and abundant functional groups. Adsorption performance was investigated by analyzing the effects of such factors as the initial pH, contact time with different initial concentration, and initial Pb(II) concentration at different temperature. The kinetic data were fitted to pseudo-second-order and intraparticle diffusion kinetic models. The results were better fitted by the pseudo-second-order kinetic model. Intraparticle diffusion increased with an increase of initial concentration and the sorption process was controlled by film diffusion. The Langmuir isotherm model was fitted to the experimental data significantly better than Freundlich and Dubinin-Radushkevich isotherm models. The maximum adsorption capacity was 97.10 mg g(-1), according to the Langmuir isotherm model. Thermodynamics parameters confirmed the spontaneous, endothermic, and entropy-gained nature within the studied temperature range (from 298 to 318 K). The composites could be effectively desorbed by the 2.0 mol L(-1) HNO3 solution and would be a potential adsorbent.

Based on polyaniline/silica gel composites (PAS) as support and functional monomer, the surface imprinted polymers (MIP–PAS) were synthesized for the selective adsorption of 2,6-dichlorophenol (2,6-DCP) from aquatic environment. The MIP–PAS was characterized by FTIR spectroscopy, scanning electron microscopy, nitrogen adsorption–desorption analysis, particle-size and EDX analysis. The effects of pH, initial analyte concentration, contact time and temperature of medium on the adsorption were studied. Equilibrium data, at various temperatures, can be described well by the Langmuir isotherm model. Kinetic can be described by the pseudo-first-order model, pseudo-second-order model, and by an intraparticle diffusion equation. A diffusion-controlled process as the essential adsorption rate-controlling step was also obtained. Moreover, intraparticle diffusion coefficient ( k i ) and pore diffusion coefficient ( D 2 ) for MIP–PAS elevated with the increased of 2,6-DCP concentration and temperature of medium, while increase in 2,6-DCP concentration was found to reduce film diffusion. Furthermore, the values of film diffusion coefficient ( D 1 ) were lower than those of D 2 , indicating the diffusion process was controlled by film diffusion. Thermodynamics parameters (positive values for delta H ° and delta S °, negative values of delta G °) indicated that the process is endothermic and spontaneous. The selectivity of the imprint also demonstrates high affinity for 2,6-DCP over related phenolic compounds and over non-imprinted polymers (NIP).

The chitosan/fly-ash-cenospheres/γ-Fe(2)O(3) (CTS/γ-Fe(2)O(3)/FACs) magnetic composites were prepared by microemulsion process. The resulting composites were characterized by XRD, FT-IR, SEM, TGA, DTG and VSM, and the results indicated that CTS/γ-Fe(2)O(3)/FACs exhibited magnetic property (M(s)=6.553 emu g(-1)) and thermal stability, and composed of chitosan wrapping magnetic γ-Fe(2)O(3) and fly-ash-cenospheres (thickness of the cross-linked chitosan was about 5.2 μm). Then the CTS/γ-Fe(2)O(3)/FACs were employed as adsorbents for the fast removal of bisphenol A (BPA) and 2,4,6-trichlorophenol (TCP) from aqueous solutions. The adsorption performances of CTS/γ-Fe(2)O(3)/FACs were investigated by batch mode experiments with respect to pH, temperature, initial concentration, contact time and binary solution system. The Langmuir isotherm model was fitted to the equilibrium data better than the Freundlich model, and the kinetic properties were well described by the pseudo-second-order equation. The effects of binary solution systems also demonstrated that BPA adsorption onto CTS/γ-Fe(2)O(3)/FACs was more affected by the simultaneous presence of competitive phenolic compound than that of TCP. In addition, the resulting composite reusability without obviously deterioration in performance was demonstrated by at least three repeated cycles.

Magnetic imprinted polymers (MIPs) were synthesized by Pickering emulsion polymerization and used to adsorb erythromycin (ERY) from aqueous solution. The oil-in-water Pickering emulsion was stabilized by chitosan nanoparticles with hydrophobic Fe 3 O 4 nanoparticles as magnetic carrier. The imprinting system was fabricated by radical polymerization with functional and crosslinked monomer in the oil phase. Batches of static and dynamic adsorption experiments were conducted to analyze the adsorption performance on ERY. Isotherm data of MIPs well fitted the Freundlich model (from 15 °C to 35 °C), which indicated heterogeneous adsorption for ERY. The ERY adsorption capacity of MIPs was about 52.32 μmol/g at 15 °C. The adsorption kinetics was well described by the pseudo-first-order model, which suggested that physical interactions were primarily responsible for ERY adsorption. The Thomas model used in the fixed-bed adsorption design provided a better fit to the experimental data. Meanwhile, ERY exhibited higher affinity during adsorption on the MIPs compared with the adsorption capacity of azithromycin and chloramphenicol. The MIPs also exhibited excellent regeneration capacity with only about 5.04% adsorption efficiency loss in at least three repeated adsorption–desorption cycles.

The inactivation of Escherichia coli with hydroxyl radical liquor that strong ionization discharge produced was studied experimentally. The relation of initial content of bacterium, initial PH value, and temperature and ratio concentration of hydroxyl radical to the inactivation rate of Escherichia coli was studied. The results suggests that the inactivation rate of Escherichia coli is increased with increasing of the initial content of the bacterium, and the contact time and concentration of hydroxyl radical. The better initial PH value was 7.

The extraction and purification of microcystin from microcystic aeruginosa were studied. The efficiency for microcystin extraction was assessed by comparing different polarity extraction agents. Results showed that 60% methanol has the highest efficiency. Ethanol solution could extract microcystins safely, and can be used as a massive security extraction agent. The extraction method and solid phase extraction measure were improved, and suitable flowing phase composition was chosen to detect microcystin-LR.

By grafting –SO3H and Cr(III) onto the surface of treated attapulgite (ATP) and halloysite nanotubes (HNTs), two acid–chromic chloride bi-functionalized catalysts i.e. ATP–SO3H–Cr(III) and HNTs–SO3H–Cr(III) were successfully synthesized. Then the as-prepared catalysts were characterized by SEM, TEM, EDS, XPS, BET, NH3–TPD, nitrogen adsorption–desorption and TG analysis. The catalytic activities of the synthesized ATP–SO3H–Cr(III) and HNTs–SO3H–Cr(III) were evaluated for the conversion of one-pot cellulose to 5-hydroxymethylfurfural (HMF) in an ionic liquid ([EMIM]-Cl) system. The amount of catalyst, reaction time and reaction temperature were optimized for cellulosic conversion over the two catalysts, resulting in a maximum yield of 31.20% for ATP–SO3H–Cr(III) and 41.22% for HNTs–SO3H–Cr(III) under the optimized conditions. The clay supported catalysts developed in this work showed greatly improved performances in cellulose-to-HMF conversion over other solid catalysts. In addition, the prepared catalysts could be very easily recycled, at least three times for ATP–SO3H–Cr(III) and twice for HNTs–SO3H–Cr(III) without significant loss of activity.

Fe3O4/Halloysite nanotube magnetic composites (MHNTs) were firstly prepared via an effective polyol-medium solvothermal method, and then the surface of the MHNTs was endowed with reactive vinyl groups through modification with 3-(methacryloyloxy)propyl trimethoxysilane (MPS). Based on the MHNTs-MPS, temperature responsive and magnetic molecularly imprinted polymers (t-MMIPs) were further synthesized by adopting methacrylic acid (MAA) and N-isopropylacrylamide (NIPAM) as the functional monomer and temperature responsive monomer, respectively. The as-prepared t-MMIPs were characterized by FT-IR, TEM, TGA and VSM, which indicated that the t-MMIPs exhibit magnetic sensitivity (Ms = 2.026 emu g−1), magnetic stability (especially in the pH range of 4.0–8.0) and thermal stability and are composed of an imprinted layer. The molecular interaction between 2,4,5-trichlorophenol (TCP) and MAA was investigated by 1H-NMR spectroscopy and ultraviolet absorption spectroscopy, which suggest that hydrogen bonding may be largely responsible for the recognition mechanism. The t-MMIPs were then applied to selectively recognise and release TCP molecules at 60 °C and 20 °C, respectively. The maximum amount of binding at 60 °C was 197.8 mg g−1 and 122.6 mg g−1 for t-MMIPs and temperature responsive and magnetic non-imprinted polymers (t-MNIPs), respectively. At 20 °C, about 32.3%–42.7% of TCP adsorbed by t-MMIPs was released, whereas 25.3%–39.9% of TCP was released by t-MNIPs. The selective recognition experiments demonstrated the high affinity and selectivity of t-MMIPs towards TCP over competitive phenolic compounds, and the specific recognition of binding sites may be based on the distinct size, structure and functional group to the template molecules.