摘要：
Two Co(II) complexes, [Co(INAIP)(dib)]·4H2O and [Co(INAIP)(phen)(H2O)]·H2O have been synthesized by the reaction of 5-(isonicotinamido)isophthalic acid (H2INAIP) and CoSO4·7H2O, as well as N-donor ligands, namely 1,4-di(1-imidazolyl)benzene (dib) and 1,10-phenanthroline (phen) under hydrothermal conditions. Single-crystal X-ray diffraction analysis indicates that [Co(INAIP)(dib)]·4H2O has a two-dimensional (2D) double-layer network structure with a (4, 4) topology, while [Co(INAIP)(phen)(H2O)]·H2O displays a one-dimensional chain structure, extending to a 2D net through the π–π interactions. In addition, the photoluminescence and degradation of methyl orange in a Fenton-like process using the complexes as catalysts were investigated.
摘要：
Activated palm kernel shell carbon (APKSC) was used to remove U(VI) from aqueous solutions in a batch system. The adsorption kinetics, isotherms, and effects of various parameters, such as temperature, contact time, solution pH, adsorbent dosage, and initial U(VI) concentration on the U(VI) adsorption process were studied. Equilibrium was reached after 120 min in the range of studied U(VI) concentrations and temperatures. U(VI) uptake was insignificantly affected by temperature, but was highly pH dependent, and the optimum pH for removal was 5.5. U(VI) removal efficiency increased with the increasing adsorbent dosage. U(VI) sorption capacity increased with increasing initial U(VI) concentration; any further increases in initial U(VI) concentration above a certain point caused insignificant changes in U(VI) sorption capacity. Isotherm data could be described by the Langmuir isotherm model with a maximum U(VI) adsorption capacity of 51.81 mg/g. Kinetic data were fitted to pseudo-first-order and pseudo-second-order equations, which suggested that the U(VI) adsorption onto APKSC was better reproduced by the pseudo-second-order model rather than pseudo-first-order model. Our results indicated that APKSC might be used as a cheap adsorbent in the treatment of uranium-containing wastewater.
摘要：
A new 2D Zn(II) metal-organic framework, [Zn2(dib)(1,3-BDC)2(H2O), has been synthesized by the hydrothermal reaction of 1,3-benzenedicarboxylate with ZnSO4·7H2O in the presence of 1,4-di(1-imidazoly)benzene (dib=1,4-di(1-imidazoly)benzene, 1,3-H2BDC=1,3-benzenedicarboxylate). The crystal is of monoclinic system, space group P21/n, with a=0.803 67(12) nm, b=1.332 7(2) nm, c=2.372 5(4) nm, β=97.394(3)°, V=2.519 9(7) nm3, Z=4, F(000)=1 392, R=0.052 0 and wR=0.099 4 (I>2σ(I)). The two central zinc(II) ions in the complex locate in a different coordination geometry, one is a distorted tetrahedral and the other is a distorted square-pyramidal coordination geometry, respectively. The dib ligand acts as a bridging ligand, which links the 1D double-chain into 2D layer structure. The net is linked into three-dimensional supramolecular network by O-H···O hydrogen bonds.
摘要：
Two Ni(II) metal–organic frameworks, [Ni(INAIP)(DMF)]·0.5DMF and [Ni(INAIP)(H2O)]·2H2O, have been synthesized by the reaction of 5-(isonicotinamido)isophthalic acid (H2INAIP) with NiSO4·6H2O using different reaction solvents. Single-crystal X-ray diffraction analysis indicates that [Ni(INAIP)(DMF)]·0.5DMF has a twofold interpenetrated three-dimensional (3D) framework with sra topology, while [Ni(INAIP)(H2O)]·2H2O has a two-dimensional (2D) network structure with a 4-connected (43·63) topology. In addition, the magnetic and adsorption properties of the complexes were explored.
关键词：
Direct reduced iron (DRI);Uranium;Kinetics;pH;Mechanism
摘要：
Direct reduced iron (DRI), also called sponge iron, was used for the removal of U(VI) from aqueous solution. Batch experiments were conducted to evaluate the effect of various factors including contact time, solution pH, DRI dosage and initial uranium concentration on this removal process. The result suggested that U(VI) can be rapidly removed by DRI and this removal process followed an apparent first-order reaction kinetics. The optimum pH for uranium removal was between 2.0 and 4.0. Whether U(VI) can be fully removed was influenced by the molar ratio of DRI to U(VI) in solution. The aqueous U(VI) can be removed completely when this ratio was more than ca. 1,000. The U(VI) removal capacities of DRI decreased with increasing DRI dosages at a constant concentration of U(VI), but increased almost linearly with increasing initial U(VI) concentrations at a fixed dosage of DRI. The maximum U(VI) removal capacity was 5.71 mg/g DRI. Finally, the possible mechanism of U(VI) removal by DRI was also discussed. The XPS and XRD analysis showed that U(VI) was deposited as UO3 onto DRI surface, indicating that U(VI) can be removed without reduction.
作者机构：
[Nie, Xue; Deng, Yi-Fang; Zhang, Chun-Hua; Chen, Man-Sheng] Key Laboratory of Functional Organometallic Materials, Hengyang Normal University, Department of Chemistry and Materials Science, Hengyang, Hunan 421008, China
通讯机构：
[Zhang, C.-H.] K;Key Laboratory of Functional Organometallic Materials, Hengyang Normal University, Department of Chemistry and Materials Science, China
摘要：
In the title compound, {[NiTb2(C14H8N2O5)4(H2O)4]·4H2O} n , the TbIII ion is coordinated by one water molecule and seven O atoms from four 5-(pyridine-4-carboxamido)isophthalate (L) ligands in a distorted square-antiprismatic arrangement, while the NiII ion, lying on an inversion center, is six-coordinated in an octahedral geometry by two pyridine N atoms, two carboxylate O atoms and two water molecules. One L ligand bridges two TbIII ions and one NiII ion through two carboxylate groups and one pyridine N atom. The other L ligand bridges two TbIII ions and one NiII ion through two carboxylate groups, while the uncoordinating pyridine N atom is hydrogen bonded to an adjacent coordinating water molecule. Extensive O - H...O, N - H...O and O - H...N hydrogen bonds play an important role in stabilizing the crystal structure.
摘要：
A 3d-4f coordination polymer {[NiTb 2(INAIP) 4(H 2O) 6]· 8H 2O} n (1) was obtained by hydrothermal assembly of NiSO 4·6H 2O and Tb(NO 3) 3·6H 2O with the H 2INAIP ligand. Complex 1 crystallizes in triclinic, space group P1 with a =1.009 72(5) nm, b = 1.083 43(5) nm, c =2.983 63(14) nm, V=3.209 3(3) nm 3, Z=2, C 56H 60NiTb 2N 8O 34, M r= 1765.67, D c=1.827 g·cm -3, μ=2.575 mm -1, F(000)=1 764, R int=0.031 5, R=0.0525, wR =0.131 8. Single-crystal X- ray diffraction analysis reveals that each INAIP 2- ligand uses its two carboxyl groups to connect two/three Tb(III) centers, and the Ni(II) only bonds to one pyridyl group and terminal water molecules, forming a two-dimensional (2D) bilayer. On the other hand, the 2D layers are further connected by hydrogen bonding interactions to give a three-dimensional (3D) supramolecular structure. The complex 1 at room temperature shows typical green photoluminescence of rare earth Tb 3+ ion.
