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To investigate the international development status and hot trends in the field of environmental security management in recent years, the published the environmental security management literature from 1997 to 2021, which was retrieved from Web of Science, with VOSviewer as the main and CiteSpace as the auxiliary, through the cooperation network of authors, scientific research institutions, and countries. The keywords were visualized by clustering, time zone analysis, and burst analysis. A total of 7596 articles were retrieved, forming six main clustering labels, including 28,144 authors. The research hotspots are from the fields of personal health, society, agriculture, ecological environment, energy, and sustainable development, as well as the development of internet environmental safety management, such as big data, Bayesian networks, and conceptual frameworks. Through cluster analysis, the cooperation of major research teams and scientific research institutions and the cooperation and development between countries were analyzed. The cooperation between scientific research institutions in various countries is relatively close. The United States currently occupies a dominant and authoritative position in this field. China has cooperated more closely with the United States, Britain, Australia, and India.

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.

As a natural plant material with unique porous structure, loofah is used in many fields, but there are still defects in fire safety performance in that its flammability. The melamine-modified flame retardant loofah composites (M-FR-PL) were prepared by impregnation baking method. The experimental synthesis conditions were optimized by L9 (34) orthogonal design. The flame retardancy, heat release rate (HRR), thermal stability and smoke density of the composites were analyzed. M-FR-PL6 prepared under the optimum experimental conditions had good properties: the adsorption rate of flame retardant (AR, %) was 6.8%, the limiting oxygen index (LOI, %) reached 27.5%, the vertical combustion level reached V-0, and the amount of residual char was 17.2% higher than that of loofah. The flame retardant mechanism of M-FR-PL6 was thoroughly discussed by various characterization methods. The peak of the HRR curve of M-FR-PL6 declined compared with loofah, indicating the loofah after melamine flame-retardant treatment has good flame retardancy and smoke suppression properties.

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.

Two kinds of hollow silica materials, namely H-SiS1 and H-SiS2, were synthesized using the yeast template method and the Pickering emulsion polymerization method, respectively. The adsorbents were synthesized to adsorb amoxicillin (AMX) from an aqueous environment. Characterization results indicated that hollow silica adsorbents exhibited excellent thermal stability even at temperatures above 700 °C. Several batches of static adsorption experiments were prepared to analyze the adsorption performance on AMX. Isotherm data on different adsorbents fitted well with the Langmuir model (from 15 °C to 35 °C), indicating a monolayer molecular adsorption mechanism for AMX. The maximum adsorption capacities of H-SiS1 and H-SiS2 were 8.40 and 3.46 mg/g at 35 °C, respectively. The adsorption kinetics was described well by the pseudo-second-order model, which indicated that chemical interactions were primarily responsible for AMX adsorption and could be the rate-limiting step during adsorption. These results suggested that H-SiS1 could be significantly useful as adsorbents for removal of AMX residuals from aqueous solution.

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%.

To improve the flame retardancy of low density polyethylene (LDPE), the intercalation of modified kaolin with urea (KU) was prepared by mechanochemical method and combined with intumescent flame retardant (IFR) as LDPE flame retardant in this paper. KU was used as synergistic flame retardant. The mechanical properties, flame retardant properties and smoke properties of KU/SiO2@MAPP/DPER/LDPE composites were investigated. The results demonstrated that the intercalation rate of KU was 63% and the addition of KU effectively improved many aspects of LDPE's performance. When 3 wt% KU were added, the LOI of SiO2@MAPP/DPER/LDPE increased from 24.1% to 27.2% and the UL-94 reached V-1. The tensile strength was 16.6 MPa and the elongation at break was 554%. The smoke density test showed that the flue gas emission was obviously improved. Raman test showed that the R value of LDPE3 was 0.96. The addition of KU effectively increased the residual carbon content of composites and thermal stability of the composites.

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.

Biosorbents have demonstrated great potential in the treatment of metal-containing wastewater. However, one of the bottleneck issues of using biosorbents is that amounts of organic carbon release f...

Thermal-responsive and magnetic molecularly imprinted polymers (TMMIPs) based on Fe3O4@carbon (Fe3O4@C) were prepared by free radical polymerization and applied to selective adsorption and controlled release of 2,4,5-trichlorophenol (2,4,5-TCP) from aqueous solution. TMMIPs were composed of multilayer structure, and exhibited magnetic sensitivity, magnetic stability and thermal stability (especially below the. The reversible transform of mean diameter resulted from the change of testing temperature, indicating the thermo-responsive properties of TMMIPs. Selective adsorption and controlled release of 2,4,5-TCP were also investigated at 25 °C and higher temperature (such as 45 °C and 60 °C), respectively.

Fly-ash-cenospheres/Fe 3 O 4 magnetic particles (MFACs) were firstly achieved by co-precipitation technique. After endowing with reactive vinyl groups onto the surface of MFACs, magnetic molecularly imprinted polymers (MMIPs) based on the modified MFACs were further prepared by suspension polymerization. The as-prepared MMIPs were charcterized, and the results indicated that spherical MMIPs exhibited superparamagnetic property ( M s = 20.99 emu g −1 ), magnetic stability (at the pH = 6.0), thermal stability ( −1 . The selectivity results showed that MMIPs had the specific adsorption for NP molecules, and the recognition process may be related to the size, structure and functional group of the template molecules.

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.

The first use of yeast as a support in the molecular imprinting field combined with atom transfer radical polymerization was described. Then, the as-prepared molecularly imprinted polymers were characterized by Fourier transmission infrared spectrometry, scanning electron microscope, thermogravimetric analysis, and elemental analysis. The obtained imprinted polymers demonstrated elliptical-shaped particles with the thickness of imprinting layer of 0.63 μm. The batch mode experiments were adopted to investigate the adsorption equilibrium, kinetics, and selectivity. The kinetic properties of imprinted polymers were well described by the pseudo-second-order kinetic equation, indicating the chemical process was the rate-limiting step for the adsorption of cefalexin (CFX). The equilibrium data were well fitted by the Freundlich isotherm, and the multimolecular layers adsorption capacity of imprinted polymers was 34.07 mg g(-1) at 298 K. The selectivity analysis suggested that the imprinted polymers exhibited excellent selective recognition for CFX in the presence of other compounds with related structure. Finally, the analytical method based on the imprinted polymers extraction coupled with high-performance liquid chromatograph was successfully used for CFX analysis in spiked pork and water samples.

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.

Removal of strontium(II) ions from aqueous solutions by potassium tetratitanate whisker (PTW) and sodium trititanate whisker (STW) was studied by the batch sorption system. Both PTW and STW possessed special lamellar structure, high surface area and strong ability for cation exchange which were all benefit for the sorption process. The batch mode sorption experiments with respect to different pH, ionic strength, temperature, initial concentration and contact time were investigated. The sorption capacity of PTW and STW were both increased with increasing pH, temperature and initial concentration of strontium(II) ions. Moreover, the sorption capacity of STW was more sensitive to the ionic strength than that of PTW. The Langmuir model represented a better fit to the experimental data than Freundlich isotherm model, and the monolayer sorption capacity of PTW was higher than that of STW at the same conditions. The kinetic data were well fitted to the pseudo-second-order kinetic model and the ion-exchange model was important only in the fist 30 min. Intraparticle diffusion increased with the increase of temperature and initial concentration. Three distinct steps were involved in the strontium(II) ions sorption onto PTW and STW, and the whole sorption processes were controlled by the film diffusion. The thermodynamic parameters (positive values Δ G °, Δ H ° and Δ S °) confirmed the non-spontaneous, endothermic and entropy gained nature within the temperature range evaluated.

Adsorption of Cr(III) and Fe(III) onto chitosan/attapulgite composites (CTS/ATP) was investigated with respect to pH, temperature, initial concentration and binary solution. Equilibrium data, at various temperatures, were described by the Langmuir, Freundlich isotherm models. The Freundlich isotherm model was fitted to the experimental data significantly better than the Langmuir isotherm. In a binary solution, the combined effect of adsorbing one metal ion in the presence of the other metal ion reduced the adsorption capacity of either metal ion. The kinetic data was well fitted to the intraparticle diffusion equation, which indicated that the three adsorption steps belonged to the pseudo-second-order adsorption process. Intraparticle diffusion increased with the increase in adsorbate concentration while film and pore diffusion decreased. The thermodynamics parameters (positive values of ΔH°, ΔS° and negative values of ΔG°) indicated the binding systems between CTS/ATP and adsorbate were endothermic, entropy gained and spontaneous in nature.

Photocatalysis of supported TiO2 film photocatalyst in a pulsed discharge system for phenol degradation was studied in this paper. The obtained results revealed that the supported TiO2 film with anatase structure had preferable photocatalytic activity in the pulsed discharge system. Phenol degradation and main byproduct generation were better in the discharge/TiO2 system. The photocatalyst prepared with eight times dipping process had higher photocatalytic activity than other photocatalysts and testified a preferable photocatalyst condition in the pulsed discharge system. Furthermore, the supported TiO2 photocatalyst kept photocatalytic activity after using five times in the pulsed discharge system.

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 first use of yeast as a support in the molecular imprinting field combined with atom transfer radical polymerization was described. Then, the as-prepared molecularly imprinted polymers were characterized by Fourier transmission infrared spectrometry, scanning electron microscope, thermogravimetric analysis, and elemental analysis. The obtained imprinted polymers demonstrated elliptical-shaped particles with the thickness of imprinting layer of 0.63 μm. The batch mode experiments were adopted to investigate the adsorption equilibrium, kinetics, and selectivity. The kinetic properties of imprinted polymers were well described by the pseudo-second-order kinetic equation, indicating the chemical process was the rate-limiting step for the adsorption of cefalexin (CFX). The equilibrium data were well fitted by the Freundlich isotherm, and the multimolecular layers adsorption capacity of imprinted polymers was 34.07 mg g(-1) at 298 K. The selectivity analysis suggested that the imprinted polymers exhibited excellent selective recognition for CFX in the presence of other compounds with related structure. Finally, the analytical method based on the imprinted polymers extraction coupled with high-performance liquid chromatograph was successfully used for CFX analysis in spiked pork and water samples.

Performance and characteristics of biosorption of Pb(II) had been studied in a batch system using the fungal strain biomass, KC-2. The biosorption performance was investigated by analysing the effects of such factors as the initial pH, initial Pb(II) concentration, and contact time at 303 K. The maximum Pb(II) adsorption was obtained at pH 5.0. The experimental data were described by the pseudo first-order, pseudo second-order and intraparticle diffusion kinetic models, and were closely followed the pseudo second-order kinetic model. The equilibrium experimental data were well fitted to Langmuir model and the maximum biosorption capacity was 84.03 mg g(-1). The adsorption mechanism was examined by FTIR, SEM and EDAX analysis. Results indicated that carboxylic, hydroxyl and amine groups were involved in the biosorption and ion exchange mechanism existed.

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.