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Highlights: [•] (Liquid+liquid) equilibrium for quaternary system was measured. [•] The components include benzene, cyclohexane, N,N-dimethylformamide, sodium thiocyanate. [•] The (liquid+liquid) equilibrium data can be well correlated by the NRTL model. [•] Separation of benzene and cyclohexane by NaSCN+DMF was discussed. [ABSTRACT FROM AUTHOR]

(Liquid + liquid) equilibrium (LLE) data were measured experimentally at T = (298.15 or 303.15) K and atmospheric pressure for the (benzene + cyclohexane + dimethyl sulfone (DMSO)) system. The Othmer–Tobias equation was applied to verify the reliability of the data. Based on the data, the selectivity of DMSO was estimated and compared with that of ionic liquids. The highest selectivity coefficient of DMSO can reach beyond 14, which means it is able to compete with some ionic liquids and it would be a good extractant to separate benzene from cyclohexane. At the same time, the NRTL model was used to correlate the data and the results show that the model agrees on the experimental data very well. [ABSTRACT FROM AUTHOR]

By using aromatic amino acid as the starting material, a novel chiral catalyst support, porous hypercrosslinked amino acid polymer was synthesized, the recyclable asymmetric metal supported by it catalyzed efficient asymmetric reaction with high ee% (up to 99%). [Display omitted] • Synthesis of a new chiral catalyst support, porous hypercrosslinked amino acid (HCP-AA). • A new heterogeneous asymmetric catalyst. • High enantioselectivity of HCP-AA-Rh for asymmetric hydrosilylation of ketones and olefins (ee% up to 99%). • HCP-AA-Rh can be easily recycled and well maintain the catalytic performance after recycle. The application of asymmetric catalysis in industrial processes is limited by the high cost of chiral ligands and the difficulty associated with recovering precious metal catalysts. Here, based on a FeCl 3 -catalyzed Friedel–Crafts alkylation reaction, an aromatic amino acid was crosslinked with 4,4′-bis(chloromethyl)-1,1′-biphenyl to produce a novel porous chiral catalyst support, hypercrosslinked amino acid polymer (HCP-AA). Subsequently, metal catalysts were loaded on HCP-AA through the coordination of the metal ion with amino acid residues to generate heterogeneous asymmetric catalysts, HCP-AA-M. The resulting catalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The HCP-AA-M samples were employed to catalyze the heterogeneous asymmetric reaction, and they achieved high enantioselectivities (up to 99% ee). Meanwhile, the catalysts could be readily recovered through filtration, and they exhibited good recycling performances. The results suggested that the utilization of inexpensive amino acids as raw materials for producing porous chiral supports for recyclable high-performance asymmetric catalysts is an effective strategy. [ABSTRACT FROM AUTHOR]

In this study, carboxylated graphene oxide (GO-COOH) was prepared via a simple and feasible method to enhance the adsorption of U(VI). GO-COOH were characterized by FT-IR, XRD and XPS technique, and then applied as the adsorbent for U(VI) ions removal from water. The effects of conditions for U(VI) adsorption, including initial pH of aqueous solution, adsorbent dose, contact time, and initial concentration of U(VI) solution were investigated. The result indicated that the maximum adsorption of U(VI) on GO-COOH was 315 mg/g at the optimum adsorption condition (C a = 0.2 g/L, pH = 6.0, t = 6 h, C 0 = 100 mg/L and T = 25 °C), which was significantly higher than that on GO (190 mg/g) in the same condition. Compared to GO, the maximum U(VI) adsorption capacity of GO-COOH increases by 65.8%. The adsorption process was described well with pseudo-second-order kinetics and the Langmuir isotherm model, indicating the chemisorption process and monolayer adsorption process. GO-COOH with increased carboxyl group content and expanded interface distance was successfully prepared from GO via a facile method. GO-COOH showed the enhanced adsorption of U(VI) compared to GO. Adsorption process was mainly dominated by chemisorption and monolayer adsorption. Image 1 • GO-COOH with increased carboxyl group content and expanded interface distance was prepared from GO via a facile method. • GO-COOH showed obviously higher adsorption capacity of U(VI) than GO. • The adsorption process for U(VI) was mainly dominated by chemisorption and monolayer adsorption. [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]

• Peptidomimetics with an alkyl substituent were synthesized from amino acids. • The peptidomimetics exhibit broad-spectrum and efficient antibacterial properties. • The peptidomimetics have the potential to combat drug-resistant bacteria. • The peptidomimetics showed good antitumor activity and low cytotoxicity. Thirteen cationic peptidomimetics derived from amino acids bearing an alkyl or ethynylphenyl moiety that mimic the structure of cationic antibacterial peptides were designed and synthesized using a simple coupling reaction of an amino acid with a substituted amine. Antibacterial activities of the resulting peptidomimetics against drug-sensitive bacteria, such as Gram-positive Staphylococcus aureus (S. aureus) and Bacillus subtilis , Gram-negative Escherichia coli (E. coli) and Salmonella enterica , and a drug-resistant bacterium, methicillin-resistant S. aureus (MRSA), were systematically evaluated. Most peptidomimetics show significant broad-spectrum antibacterial activity. A-L-Iso-C 12 (isoleucine derivative bearing a dodecyl moiety) show MICs of 2.5 μg/mL against S. aureus and 4 μg/mL against MRSA and A-L-Val-C 12 (valine derivative bearing a dodecyl moiety) show MICs of 1.67 μg/mL against E. coli and 8.3 μg/mL against MRSA. A-L-Val-C 12 showed low cytotoxicity toward L929 cells in comparison with SGC 7901 cells, indicating tumor-directed killing by peptidomimetics while avoiding toxicity to normal cells. The influences of type of amino acid and substituent, length of substituent, and stereochemistry of amino acids on antibacterial activity and cytotoxicity of peptidomimetics were systematically investigated. The results indicate that this series of cationic peptidomimetics derived from amino acids display antitumor activity and may be useful for treatment of bacterial infections. [ABSTRACT FROM AUTHOR]