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Chiral resolution of binaphthylamine is often a toilful conundrum in the field of analytical chemistry and biomedicine. The work puts forward a selective, sensitive, and miniaturized analytical method based on molecularly imprinted polymers (MIPs) as adsorbent for miniaturized tip solid‐phase extraction (MTSPE) in the separation of binaphthylamine enantiomer. This method combines the advantages of MIPs (high selectivity), MTSPE (low consumption), and high‐performance liquid chromatography (HPLC, high sensitivity). A simple synthesis methodology of MIP (P2) was conducted through bulk polymerization with (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diamine (S‐DABN) as template together with methacrylic acid monomer, and ethylene glycol dimethacrylate as cross‐linker in proper porogen, realizing a selective recognition and efficient enrichment for S‐DABN. The method exhibited appreciable linearity (0.06–1.00 mg ml−1), low quantification limit (0.056 mg ml−1), good absolute recoveries (45.70%–69.29%), and high precision (relative standard deviations ≤ 3.54%), along with low consumption (0.50 ml sample solution and 25.0 mg adsorbent). Based on the density functional theory, computational simulation was used to make a preliminary prediction for rational design of MIPs and gave a reasonable elaboration involving the potential mechanism of templates interacting with functional monomers. The adsorption kinetics and thermodynamics were investigated to evaluate the recombination process of substrates. In addition, the selectivity of MIPs for S‐DABN was obtained by MIP‐MTSPE coupled with HPLC, which supports the feasibility of this convenient design process. The proposed method was employed for selective extraction of S‐DABN and exhibited promising potential in the application of chiral analysis. [ABSTRACT FROM AUTHOR]

The removal of U (VI) from wastewater is an arduous technological task wherein biofouling caused by microorganisms severely depletes the relevant properties of adsorbents. Herein, the zeolitic imidazole frameworks dubbed ZIF-90 were functionalized with amidoxime via the production of a diaminomaleonitrile intermediate to manufacture a highly efficient U (VI)-adsorbing material with antibacterial properties called amidoxime-appended ZIF-90 (ZIF-90-A). The crystal and pore structures of ZIF-90 and its modified materials were characterized by FT-IR, XRD, SEM, XPS and BET. ZIF-90-A has a superior uranium-uptake capacity (490.2 mg/g) at pH 5, which is close to the pH of wastewater. At the same time, ZIF-90-A also exhibited outstanding antimicrobial properties. Values for the minimum inhibitory concentration (MIC) of ZIF-90-A were measured to be 125 and 250 μg/mL against Staphylococcus aureus and Escherichia coli , respectively. In addition, ZIF-90-A displayed good selectivity for the adsorption of UO 2 2+; moreover, the uranium-uptake capacity of ZIF-90-A did not exhibit an obvious reduction when the adsorbent was subjected to five adsorption–desorption cycles. These results suggest that ZIF-90-A is a viable choice for the efficient removal of U (VI) from nuclear wastewater. [Display omitted] • A novel U (VI) adsorbent ZIF-90-A with good anti-fouling property is prepared. • ZIF-90-A shows good antimicrobial activity against S. aureus and E. coli (MICs = 125 ~ 250 μg/mL). • ZIF-90-A shows efficient U (VI) adsorption performance (Q e = 490.2 mg/g, pH = 5). • The possible mechanisms of U (VI) adsorption and antimicrobial are illustrated. [ABSTRACT FROM AUTHOR]

Surface molecularly imprinting polymer (SMIP) was utilized in the removal of a residual pesticide (carbaryl (CBL)) in water and simulated fruit juice. Being the crosslinking agent, ethylene glycol dimethacrylate (EGDMA) was copolymerized with the monomer, methacrylic acid (MAA) and CBL as the template molecules on the surface of the silica gel particles to produce the SMIP adsorbents. The SMIP adsorbents showed good selectivity and good adsorption capacity for CBL in the competitive adsorptions with two structurally related carbamate pesticides. The effect of the pretreatment solvents on the adsorption capacity of the SMIP adsorbent was investigated with the results of the numerical simulations. The adsorption isotherms and the adsorption kinetics were well described by the Freundlich equilibrium model and the pseudo-second-order kinetic model, respectively. Scatchard plot analysis revealed that there were two classes of binding sites populated in the SMIP adsorbents. In addition, the good selective adsorption of CBL by the SMIP adsorbent in a simulated fruit juice containing vitamin C and fructose indicated the great potential of the SMIP adsorbents to remove residual pesticide in food industry and processing industry for agricultural products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Easily treated organic porous hyper-cross-linked polymers and big BET surface area. • A novel phosphate esterification hyper-cross-linked polymer was prepared. • PHCP-BF has a maximum sorption capacity of 120 mg/g. • High selective and good regeneration of PHCP-BF. There is a strong need for the development of effective uranium sorbents. Here, the Friedel-Crafts reaction was performed in a simple one-step manner followed by phosphate esterification to prepare porous hyper-cross-linked Bisphenol F (PHCP-BF) for prospective utilization in the removal of U(VI) from wastewater. PHCP-BF has pores with a size of 2.6 nm and a significant BET surface area (up to 387.31 m2/g). It was extensively investigated how a variety of environmental conditions (e.g., pH, contact time, temperature, etc.) affected the treatment results. In terms of adsorption capacity, uranium possessed a maximum of 120 mg/g (pH = 7), which is twice that of the original material HCP-BF (59.39 mg/g). According to the modeling results, with the Langmuir isotherm and a pseudo-second-order kinetic model, the data matched the sorption data very well. It was found that PHCP-BF possessed good selectivity for uranium, which was considerably greater than that of other co-existing metals. After three cycles, PHCP-BF still maintained a certain adsorption capacity. In light of several spectroscopic examinations, the mechanism of uranium removal by PHCP-BF is the chelated of P = O with U (VI). The results obtained suggest that PHCP-BF can be used effectively to remove uranium from water. [ABSTRACT FROM AUTHOR]

Practical adsorbents with high efficiency are essential to effectively treating wastewater. Herein, a novel porous uranium adsorbent (PA-HCP) having a considerable amount of amine and phosphoryl groups was designed and synthesized by grafting polyethyleneimine (PEI) on a hyper- cross -linked fluorene-9-bisphenol skeleton via phosphoramidate linkers. Furthermore, it was used to treat uranium contamination in the environment. PA-HCP exhibited a large specific surface area (up to 124 m2/g) and a pore diameter of 2.5 nm. Batch uranium adsorptions on PA-HCP were investigated methodically. PA-HCP demonstrated a uranium sorption capacity of >300 mg/g in the pH range of 4–10 (C 0 = 60 mg/L, T = 298.15 K), with its maximum capacity reaching 573.51 mg/g at pH = 7. The uranium sorption process obeyed the pseudo-second-order model and fitted well with the Langmuir isothermal. In the thermodynamic experiments, uranium sorption on PA-HCP was revealed to be an endothermic, spontaneous process. Even in the presence of competing metal ions, PA-HCP exhibited excellent sorption selectivity for uranium. Additionally, excellent recyclability can be achieved after six cycles. Based on FT-IR and XPS measurements, both the P O and –NH 2 (and/or –NH–) groups on PA-HCP contributed to efficient uranium adsorption as a result of the strong coordination between these groups and uranium. Furthermore, the high hydrophilicity of the grafted PEI improved the dispersion of the adsorbents in water and facilitated uranium sorption. These findings suggest that PA-HCP can be used as an efficient and economical sorbent to remove U(VI) from wastewater. [Display omitted] • Easily treated organic porous hyper-cross-linked polymers as uranium adsorbents. • Combining branched polyethyleneimine and P O linkers in an organic porous skeleton. • Efficient Uranium adsorption performance (up to 573.51 mg/g, pH = 7). • High selective adsorption for U(VI) in simulated wastewater. [ABSTRACT FROM AUTHOR]

• Synthesis of a novel U (VI) adsorbent HCP-Phenylalaninol (HCP-PAO), a porous hypercrosslinked aminol. • The hypercrosslinked product is simple to synthesize and shows porosity, large surface area and good thermodynamic stability properties. • HCP-PAO shows efficient U (VI) adsorption performance (Q e = 369.5 mg/g, pH = 7) and long service life. • HCP-PAO shows good selective toward uranium at simulated seawater. Uranium mining from seawater has sparked a lot of research curiosity. Here, we synthesized a porous hypercrosslinked phenylalaninol (HCP-PAO) for U (VI) adsorption from water, in which phenylalaninol bearing amino and hydroxyl groups was used as the monomer, and biphenyl dichlorobenzyl (BCMP) was used as the external crosslinker. The resulting porous adsorbent has a surface area of 562.6 m2/g and a pore volume of 0.41 cm3·g−1. The pore size distribution is focused around 3–4 nm, indicating that it is a typical mesoporous polymer. The adsorbent had the most promising adsorption performance at pH = 7, reaching adsorption saturation in a 100-ppm uranium-doped solution for 2 h (adsorption capacity of 369.5 mg/g). HCP-PAO was particularly sensitive to uranium in complicated settings (56.3 % removal rate), and the adsorption mechanism closely resembled the Langmuir model and the pseudo-second-order model well. The practically consistent adsorption capacity of the HCP-PAO after five adsorption/resolution studies indicated its high recyclability. The mechanism of uranium extraction by HCP-PAO is the synergistic coordination of –NH 2 and –OH with U (VI). HCP-PAO had an adsorption capacity higher than 100 mg/g at pH = 8 which is close to the pH of natural seawater, and showed good selectivity for U (VI) in simulated seawater experiments (removal rate over 55 %). Our research suggests that the novel hypercrosslinked product HCP-PAO can be applied as an adsorbent to efficiently capture U (VI) from water, and also it has great potential in seawater uranium extraction as well as expanding the research concept of porous uranium adsorbent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carboxyl and amidoxime bifunctional polymer was grafted on MIL-101 via surface initiated ATRP; • Highly efficient uranium adsorbent, adsorption capacity reached 1086 mg·g−1; • Synergistic effect of carboxyl and amidoxime groups promote uranium adsorption; • High uranium selectivity and reusability of adsorbent in simulated seawater. Nuclear energy can effectively alleviate the carbon emission problem caused by fossil fuels. Herein, a highly effective uranium adsorbent MIL-101-SMA-AO modified with carboxyl and amidoxime groups was prepared by a surface-initiated atom transfer radical copolymerization (ATRP) of styrene and maleic anhydride on MIL-101 (Cr) and the subsequent amidoximation. MIL-101-SMA-AO shows ultra-high BET specific surface area (greater than1300 m2∙g−1) and high efficiency adsorption performance, the maximum uranium adsorption capacity reached 1086 mg·g−1. It also shows high selectivity for U (VI) in a simulated seawater and excellent recyclability, the uranium adsorption capacity slightly dropped after five adsorption/desorption cycles. The affecting factors of uranium adsorption process were investigated by batch adsorption experiments under different adsorption conditions. Besides, the results of adsorption kinetics and thermodynamics show that the adsorption process of MIL-101-SMA-AO on U (VI) is controlled by chemical rate and is monolayer adsorption. The synergistic effect of carboxyl and amidoxime groups on the strong chelation with uranium were thought to afford the adsorbent high adsorption property and selectivity for uranium. MIL-101-SMA-AO provides a valid and promising program for the study of uranium extraction from seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amino acids were grafted onto MIL-101 to produce novel uranium adsorbents. • Histidine-modified MIL-101 shows the highest U(VI) adsorption capacity of 345 mg·g−1. • Imidazole and carboxyl group and large specific surface area play important role. Three novel uranium adsorbents were synthesized by modifying MIL-101 with three amino acids: glycine, histidine and cysteine. The BET (Brunauer-Emmett-Teller) specific surface areas of amino acid modified MIL-101 (MIL-101-Gly, MIL-101-His and MIL-101-Cys) are 429 m2∙g−1, 713 m2∙g−1 and 104 m2∙g−1, respectively, indicating that the modified MIL-101 retained high specific surface area. All the modified MIL-101 s showed good uranium adsorption performance, in which the uranium adsorption performance of MIL-101-His is the best that can reach 345 mg·g−1 at pH = 6. The adsorption process of three amino acid modified MIL-101 s all accord with Langmuir and pseudo-second-order model for monolayer chemical adsorption. In the existence of K, Ca, Na, Sr, Ba, Cd, Co and Pb, the uranium (VI) removal rate of MIL-101-His can reach 74% indicating its excellent selectivity. After five adsorption–desorption cycles, the adsorption capacity of MIL-101-His still remains good capacity of 300 mg·g−1. In short, we prepared three novel amino acid modified MIL-101 s, and the histidine modified MIL-101 showed the best uranium adsorption performance, including adsorption capacity, selectivity and recyclability. [ABSTRACT FROM AUTHOR]

Herein, a dual-function Zeolitic Imidazole Frameworks (ZIFs) ZIF-90 grafted with malononitrile by Knoevenagel reaction and following with an amidoximation reaction to form an efficient U (VI) adsorbent (ZIF-90-AO). The strong chelation power of amidoxime groups (AO) with uranium and ZIF-90 's mesoporous structure afforded ZIF-90-AO high maximum uranium adsorption capacity of 468.3 mg/g (pH = 5). In addition, the factors affecting uranium adsorption process were investigated by a batch of adsorption tests under different adsorption conditions. ZIF-90-AO displayed good selectivity to UO 2 2+ in the solution containing multiple co-existing ions and good regeneration property. More importantly, ZIF-90-AO showed excellent antimicrobial property against both E. coli and S. aureus. Therefore, ZIF-90-AO is a U-adsorbent with great application value for removing U (VI) from wastewater due to the high U (VI) adsorption capacity in weak acid condition and good anti-biofouling properties. [Display omitted] • A novel U (VI) adsorbent ZIF-90-AO with good anti-fouling performance is prepared. • The maximum U (VI) adsorption capacity of ZIF-90-AO (468.3 mg/g) is much higher than ZIF-90 at pH = 5. • The MICs of ZIF-90-AO against E. coli and S. aureus are 250 and 62.5 mg/L, respectively. • Perspectives about the adsorbent (ZIF-90-AO) for the removal of U (VI) from wastewater are presented. [ABSTRACT FROM AUTHOR]

Here, copoly (styrene / maleic anhydride) was hypercrosslinked using a simple Friedel–Crafts acylation reaction to produce a novel porous hypercrosslink polymer bearing carboxy groups (C-SMA). As a support, C-SMA was loaded with Fe 3 O 4 through a solvothermal method to produce a magnetic uranium adsorbent (Fe 3 O 4 @C-SMA), which was systematically characterized using FT-IR, TGA, SEM, XRD, VSM, BET, and XPS. Uranium adsorption was carried out by using Fe 3 O 4 @C-SMA under different conditions to evaluate its uranium adsorption capacity. The adsorbent shows good uranium adsorption performance (178 mg·g−1 at pH = 6), has excellent stability, and can be readily magnetically recovered. The porous framework of C-SMA avoided the magnetic agglomeration effect of bare Fe 3 O 4. XPS analysis indicates that both the carboxy groups and Fe 3 O 4 contribute to the uranium adsorption on Fe 3 O 4 @C-SMA. [Display omitted] • A novel hypercrosslinked material was prepared by Friedel–Crafts acylation reaction. • Fe 3 O 4 was loaded on hypercrosslinked polymer through solvothermal method. • Magnetic recovery and reusable uranium adsorption material. • High selective uranium adsorption selectivity in simulated seawater. [ABSTRACT FROM AUTHOR]

[Display omitted] • • ZIF-90 and ZIF-90-OM are introduced into U-adsorbent for the first time. • • The maximum U-capacity of ZIF-90-OM (610 mg/g) is much higher than ZIF-90 at pH = 5. • • The removal rate of ZIF-90-OM to U (VI) is above 0.75 in the coexistence of competitive ions. • • Both ZIF-90 and ZIF-90-OM show good antimicrobial property. • • Perspectives about the adsorbent (ZIF-90-OM) of removing uranium from wastewater are presented. The anti-fouling performance of an adsorbent is important for its application in wastewater, because biological fouling severely reduces its adsorption capacity. A zeolitic imidazolate framework was synthesized and oxime-functionalized to produce an efficient uranium adsorbent with antimicrobial properties (ZIF-90-OM). Its adsorption performance for U (VI) was studied under different environmental parameters, including pH, initial uranium concentration, competitive ions, ionic strength, temperature, and contact time. Due to its porous structure and the strong chelation of oxime groups with U (VI), ZIF-90-OM showed a very high maximum adsorption capacity for U (VI) of 610 mg/g at pH = 5.0. The adsorption of uranium on ZIF-90-OM correlated well with the Langmuir model and the pseudo-second-order kinetic model. ZIF-90-OM showed high uranium selectivity even in the presence of competing metal ions. Besides, the adsorbent also exhibits good recyclability, the adsorption capacity was maintained after five adsorption/desorption cycles. Furthermore, ZIF-90-OM showed excellent antimicrobial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Our work shows that ZIF-90-OM is an efficient adsorbent for the removal of U (VI) from wastewater because of the presence of oxime groups and its anti-fouling properties. Moreover, due to its antimicrobial properties, ZIF-90-OM can be used to purify water. [ABSTRACT FROM AUTHOR]

Uranium (U) is hazardous and radioactive, wastewater containing U(VI) should be treated before being discharged. Here, two novel uranium adsorbents, phosphorylated hyper-cross-linked bisphenol A (PHCP-1) and fluorene-9-bisphenol (PHCP-2) were separately synthesized via Friedel-Crafts reaction followed by phosphorylation using phosphorus oxychloride. PHCPs had a BET surface area (up to 564 m2/g) with pore sizes of 2.2–2.8 nm. These adsorbents were used for the first time for uranium adsorption from water and demonstrated outstanding adsorption performance. PHCP-2 had a great uranium adsorption capacity (297.14 mg/g) and a very fast sorption rate (85% removal rate within 5 min). The adsorption data were well fitted with Freundlich isotherm and the pseudo-second-order kinetic model. PHCPs displayed selective adsorption capacity for U(VI) from solution that including a variety of competing metal ions. The reusability was confirmed through three regeneration cycles. Based on a series of spectroscopic analyses, the mechanism of action between PHCPs and U(VI) is primarily derived from the complex between phosphate functional groups and U (VI). The sorption performance of PHCPs is attributed to their huge specific surface area and the strong complex between phosphate groups and U(VI). These findings suggest that PHCPs could be useful in the effective adsorption of uranium from water. [Display omitted] • Phosphorylation was performed on bisphenol type hyper-cross-linked polymer for the first time. • PHCPs have large BET surface area (PHCP-2 = 564 m2/g). • PHCP-2 showed a very fast sorption rate, the removal rate reached 85% within 5 min. • PHCPs showed selective adsorption ability for U(VI) from solution that contained multiple competing metal ions. [ABSTRACT FROM AUTHOR]

Here, reaction of a chloromethylated metal-organic framework (MOF) MIL-101 with diaminomaleonitrile (DAMN) following with an amidoximation reaction successfully produced a novel amidoxime functionalized porous material (MIL-101-AO). The chelation of amidoxime group to uranium and the large specific surface area afforded MIL-101-AO excellent selective adsorption ability for U (VI) in aqueous solutions (586 mg·g−1). Furthermore, MIL-101-AO showed much stronger selective adsorption for U (VI) than other co-existing metallic ions in the artificial seawater (removal rate reached 96%). The influence factors on the adsorption process were evaluated by batch adsorption experiments under different condition. The process of adsorbing uranium on MIL-101-AO fitted with the Langmuir model and the pseudo-second-order kinetic model. The △H° and △G° values of uranium adsorption indicated that it was an endothermic heat process; a higher adsorption temperature could promote the adsorption on MIL-101-AO. All the experimental results indicated that MIL-101-AO was an adsorbent with the application value of extracting uranium in seawater. • Amidoxime was first grafted on chloromethylated MIL-101 via diaminomaleonitrile. • Amidoxime-modified MIL-101 shows high U(VI) sorption capacity of 586 mg/g. • High selectivity, U(VI) removal rate reaches 96% in artificial seawater. • Large surface area and strong chelating ability play important role. [ABSTRACT FROM AUTHOR]