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The potentially hazardous iron-containing sludge from the Fenton process requires proper treatment and disposal, which often results in high treatment cost. In this study, a novel method for the reuse of Fenton sludge as an iron source for the synthesis of nickel ferrite particles (NiFe

Nanoscale zero-valent iron (NZVI) supported on ordered mesoporous carbon (OMC) was synthesized through liquid phase reduction route. The NZVI/OMC composite was characterized by X-ray diffraction, N(2) adsorption/desorption and transmission electron microscopy. Results reveal that the composite possesses ordered mesostructure with NZVI distributing homogeneously on the surface of OMC support. The removal effects of nitrobenzene (NB) in water with OMC, NZVI/OMC and non-supported NZVI were evaluated. Results indicate that NZVI/OMC shows enhanced removal efficiency, which is attributed to its adsorption and synergistic reduction for NB. The transformation process of NB was further investigated by HPLC. Nitrosobenzene and phenylhydroxylamine were detected as intermediate products and aniline was the final reductive product.

Diffusion in electrochemistry is a critical issue for water purification. Electrocatalytic reactor system in improving water quality is a useful way to induce convection to enhance diffusion. This study focuses on the preparation and the characterization of Ti/SnO2-Sb tubular porous electrode for degrading pyridine wastewater. The electrode as an anode in reactor system is prepared by coating SnO2-Sb as an electro-catalyst via Pechini method on the tubular porous Ti. Scanning Electron Microscopy, Energy Dispersive Spectrum, X-ray Diffraction and Pore Distribution are employed to evaluate the structure and morphology of the electrodes coatings, and Linear Sweep Voltammetry and Cyclic Voltammetry are used to illustrate the electrochemical properties of the electrodes coatings. Furthermore, the electrochemical oxidation performance of Ti/SnO2-Sb tubular porous electrode is characterized by degrading pyridine wastewater. The effects of flow and static pattern, initial pyridine concentration, supporting electrolyte concentration, current density and pH on the performance of the reactor were investigated in the electrocatalytic reactor system. The results indicated that the removal ratio of pyridine reaches maximum which is 98% under the optimal operation conditions, that are 100 mg L(-1) initial pyridine concentration, 10 g L(-1) supporting electrolyte concentration, 30 mA cm(-2) current density and pH 3. Transition state calculation based on the density function theory was combined with High Performance Liquid Chromatography, Gas Chromatography and Ionic Chromatography results to describe the pathway of pyridine degradation.

The research on electrochemical oxidation of dinitrotoluene (DNT) wastewater assisted by Sn–Sb–Ag-modified ceramic particulates (SCP) was studied. With the assistance of SCP, the enhancement of COD removal, decrease of energy consumption and improvement in biodegradability of the wastewater were very obvious. The apparent rate constants for the removals of absorbance at 358 nm (Abs358 nm), concentration of DNT and total organic carbon (TOC) were also greatly enhanced by SCP. Mechanism of enhanced electrochemical oxidation by SCP has been evaluated from the accumulated hydroxyl radical concentration. In situ generation of the strong oxidizing agents by SCP in the electrochemical system contributed to the enhanced electrochemical oxidation performance towards organic compounds.

A simple and effective method for in situ synthesis of α-Fe nanoparticle/ordered mesoporous silica (OMS) composites is reported. Evaporation induced self-assembly (EISA) and carbothermal reduction (CR) are strategically combined by using amphiphilic triblock copolymer P123 as not only a template and but also a precursor of carbon material. P123 plays dual roles in assembly of mesostructure and reduction of ferric species. Thermogravimetric analysis–mass spectrometer was used to investigate the pyrolysis process of the wet gels. The synthesized composites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscope (XPS) and N 2 adsorption. The results showed that the composites possess ordered hexagonal mesoporous structure and the α-Fe nanoparticles with about 16 nm were well dispersed in mesoporous matrix. The carbon material resulting from P123 can reduce ferric species to α-Fe nanoparticles at 800 °C. Moreover, the formation mechanism for Fe nanoparticles in OMS matrix is proposed.

An efficient single-step approach toward the synthesis of 2-alkylquinolines is described. Through a Lewis acid mediated [3 + 3] annulation reaction between 3-ethoxycyclobutanones and aromatic amines, a variety of multisubstituted 2-alkylquinoline derivatives were prepared regioselectively at room temperature.

Short channeled Zr-Ce-SBA-15 (ZCS) mesoporous materials were synthesized through hydrothermal routes without addition of mineral acids. 0.5 wt.% palladium was loaded on ZCS and SBA-15 via an ethanol reduction approach. Pd/ZCS possesses unique hexagonal platelet morphologies with short channels running parallel to the thickness in the range of 400–500 nm, while Pd/SBA-15 has a fibrous macrostructure with channels at the micrometer scale. Palladium species present in supports as well dispersed PdO nanocrystals with diameter of ca. 5–6 nm. Comparing with Pd/SBA-15, Pd/ZCS shows enhanced catalytic activity for toluene oxidation, which is ascribed to short channeled supports facilitating the molecular diffusion.

This study investigated the electrochemical degradation of isothiazolin-ones in aqueous solution on a Ti/SnO2–Sb/PbO2 electrode. 1-Nitro-2-crylic-acetone, acetic acid and formic acid were the main degradation intermediates identified by tandem mass spectrometry (MS/MS) and the pathway for electrochemical degradation of isothiazolin-ones was proposed. Kinetic analyses indicated that electrochemical degradation of isothiazolin-ones was a pseudo-first-order reaction. The influences of operating parameters, such as electrolysis time, initial concentration of isothiazolin-ones, current density, initial pH and electrolyte flow rate on electrochemical degradation of isothiazolin-ones were investigated. Electrochemical degradation of isothiazolin-ones as well as CODcr (chemical oxygen demand determined by potassium dichromate) was controlled by mass transport.

Treatment of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) wastewater by combined process of electrocatalytic reaction and anoxic–oxic (A/O) activated sludge process was investigated. The degradation intermediates of RDX during the synergistic system of electrochemical reduction and electrochemical oxidation were analyzed by tandem mass spectrometry (MS/MS), and a pathway for electrocatalytic degradation of RDX was proposed. In order to remove RDX from the wastewater, an electrochemical system using TiO2-NTs/SnO2-Sb anode was applied to the pretreatment process. The effect of the operating parameters on the electrochemical process performance was studied. The electrocatalytic process removed 39.2% of COD and 97.5% of RDX, and increased biodegradability index from 0.18 to 0.51, which resulted in a great improvement in the biodegradability. The start-up and operation period for the anoxic–oxic activated sludge process were also investigated. As a conclusion, the toxic and refractory organic pollutants were effectively removed in the electrochemical pretreatment and this combined process was successfully employed.

Reactions of the tripodal bridging ligand 5-(4-carboxy-phenoxy)-isophthalic acid (abbreviated as H{sub 3}cpia) with lanthanide salts lead to the formation of a family of different coordination polymers, that is, [Ln(cpia)(H{sub 2}O){sub 2}]{sub n}.nH{sub 2}O (Ln=Ce (1), Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Dy (7), Er (8), Tm (9) and Y (10)) in the presence of formic acid or diethylamine, which are characterized by elemental analysis, IR spectrum, thermogravimetric analysis (TGA), XRPD spectrum and single-crystal X-ray diffraction. Compounds 1-10 are isostructural and exhibit three-dimensional microporous frameworks. Furthermore, the photoluminescent properties of 4, 5 and 7 have been studied in detail. -- Graphical abstract: Reactions of the tripodal bridging ligand (H{sub 3}cpia) with lanthanide ions lead to the formation of a series of coordination polymers in the presence of formic acid or diethylamine. Display Omitted Research Highlights: {yields} Ten new lanthanides-based coordination polymers (1-10) have been synthesized. {yields} 1-10 exhibit 3D (4,8)-connected fluorite topology networks with 1D channel parallel to the b-axis. {yields} Compounds 4, 5 and 7 exhibit characteristic luminescence of Sm{sup 3+}, Eu{sup 3+} and Dy{sup 3+} ions, respectively.

(6-Amino-2-chloro-3-fluorophenyl)methanol is prepared through both traditional methods and palladium catalyzed iterative C H halogenation reactions. In comparison to traditional approach, the C H functionalization strategy demonstrated a few advantages including milder reaction conditions, higher yields, better selectivity and practicality, and high chemical diversity.

The novel Sb-doped SnO2 electrodes (TiO2-NTs/SnO2-Sb) have been prepared by anodization, electrodeposition and annealing. TiO2 nanotubes (TiO2-NTs) after Sb and Sn electrodeposited were characterized using field-emission scanning electron microscopy (FE-SEM). In contrast with the traditional Sb-doped SnO2 coating prepared by thermal decomposition, the Sb-doped SnO2 coating prepared by electrodeposition processes show more compact. X-ray diffraction (XRD) analysis indicates that the Sb-doped SnO2 coating prepared by electrodeposition processes are firmly combined with the TiO2-NTs formed on the Ti substrate. Accelerated service life tests reveal that the electrodeposition processes enhance the electrochemical stability of the Sb-doped SnO2 electrode. The cyclic voltammetry analysis shows that TiO2-NTs/SnO2-Sb electrodes have higher overpotential for oxygen evolution and higher electrochemical porosity. Besides, the enhanced stabilization mechanism of the TiO2-NTs/SnO2-Sb electrode prepared by electrodeposition processes has been studied.

Highly ordered Fe-containing mesoporous carbon materials were directly synthesized through simple soft templating routes by using resorcinol–formaldehyde (RF) as a carbon precursor, triblock copolymer Pluronic F127 as a template agent and hydrated iron nitrite as an iron source. The main strategy of this approach is to use the acidity self-generated in the aqueous solutions of the iron precursors as the catalyst for RF polymerization and no any additional mineral acid was necessary. The resultant materials were characterized using nitrogen sorption, X-ray diffraction, and transmission electron microscopy. It was found that the final products with a highly ordered mesostructure were obtained when the Fe/R ratio was around 0.1. For those with Fe/R ratios smaller or greater than this value, the ordering decreased. Iron species in the mesoporous carbon matrix existed in two states, metallic Fe and γ-Fe 2 O 3 . Metallic Fe nanoparticles are dominantly buried in the walls of the mesoporous carbon while γ-Fe 2 O 3 nanoparticles are mostly located on the surface. The resulting materials with Fe/R ratio of 0.1 (Fe/OMC-0.10) exhibit specific activity for the catalytic wet peroxide oxidation (CWPO) of phenol solution with hydrogen peroxide. The phenol and TOC conversion can reach to 93.0% and 61.7% within 180 min at an initial of phenol 247 ppm under very mild conditions ( P = 1 atm and T = 80 °C).

An empirical model for COD removal in a biological aerated filter (BAF) in the presence of 2,4,6-trinitrophenol (TNP) was developed, which related effluent COD to influent COD or hydraulic loading rate along the bed height. The overall reaction rate for substrate biodegradation could be described as pseudo first order. The experimental data of COD removal against reactor height were used to calculate the parameters in the empirical model. The COD concentration at different reactor height was expressed as a function of influent COD concentration and hydraulic loading rate, ln( C 0 /C) = 0.124 H /Q 0.77 0 and ln(C/ 0 ) = −5.63 H / L 0.94} , respectively, under the experimental condition. The models may be used to predict the COD removal profiles along the reactor height at different hydraulic loading rates and influent COD concentration for design, selection and sizing of BAF.

A novel chelating resin with sulfonic group was synthesized by chemical modification of D401 resin with sulphonation reaction and characterized by FT-IR spectrometry. The adsorption properties of the novel chelating resin for Pb2+ were studied by batch adsorption, and the adsorption process was analyzed from thermodynamics and kinetics aspects. The adsorption mechanism of Pb2+ on the modified D401 chelating resin was discussed by FT-IR spectrometry. Experimental results show that in the Pb2+ concentration range of 200–400 mg/L, the adsorption capacities of the modified D401 chelating resin for Pb2+ increase by 77%–129%, and Langmuir isothermal adsorption model is more suitable for the equilibrium adsorption data. Adsorption is an endothermic process that runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best pH value under adsorption condition is 4–5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the adsorption capacity remains stable after five consecutive adsorption-desorption cycles. The maximal static saturated adsorption capacity of the resin is 206 mg/g at 333 K in the Pb2+ concentration range of 200–400 mg/L. The modified D401 chelating resin is an efficient adsorbent for the removal of Pb2+ from its single-metal ion solution.

The removal performance of a basic dye, methylene blue (MB), in aqueous solution was investigated by adsorption process on single-phase and high-crystalline zeolite A (FA-ZA) and X (FA-ZX). Both adsorbents FA-ZA and FA-ZX were synthesized from fly ash prepared aluminosilicate gel followed by the hydrothermal treatment at 100°C with the control of Si/Al molar ratio, respectively. The properties of the synthetic zeolites and commercial grade zeolites, such as thermal stability, elemental composition, and cation exchange capacity, were investigated for comparison. Batch method was used to study the influential parameters, such as initial pH value of the solution, temperatures, and adsorbents dosage, on the adsorption process. The experimental data were well fitted by Ho' pseudo-second-order model and liquid film diffusion model. The suitability of Langmuir and Freundlich isotherms to the equilibrium data was investigated in the solid-liquid system while the Langmuir model produces the best results. Thermodynamic data (ΔH, ΔS, and ΔG) corresponding to the MB uptake were evaluated from the Langmuir model. In all the adsorption experiments, the adsorption capacity followed the order as follows: FA-ZX > FA-ZA. In addition, attempts were also made to regenerate the adsorbents.

In this paper, an experimental and theoretical study was carried out to evaluate the performance of gas–liquid membrane contactor in benzene/nitrogen separation process by using an aqueous N-Formylmorpholine (NFM) solution as absorbent. The effects of operating parameters such as the gas and liquid flow rates, the feed gas and the initial liquid concentrations, the liquid temperature, the absorbent concentration and the long term operation on the benzene flux and removal efficiency were investigated. A mathematical model was developed to simulate the absorption process in order to gain an insight into the experimental observation. Both simulative and experimental results show that benzene mass transfer flux increases with the gas flow rate and the feed gas concentration, while the liquid flow rate has no significant effect on it. The increase in liquid temperature and initial liquid benzene concentration results in a decrease in benzene flux. Long term performance test shows that the aqueous NFM solution is a suitable absorbent to be applied to the polypropylene (PP) hollow fiber gas–liquid membrane contactor.

The adsorption behavior of Cd(superscript 2+) on 001×7 strong-acid cation exchange resin was studied with the static adsorption method. The adsorption process was analyzed from thermodynamics and kinetics aspects. The influences of experimental parameters such as pH, temperature, initial concentration and adsorption rate were investigated. The experimental results show that in the studied concentration range, 001×7 resin has a good sorption ability for Cd(superscript 2+), and the equilibrium adsorption data fit to Freundlich isotherms. The adsorption is an exothermic process which runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best adsorption condition is pH 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the desorption efficiency is over 98%. The maximal static saturated adsorption capacity is 355 mg/g (wet resin) at 293 K. The adsorption mechanism of Cd(superscript 2+) on 001×7 resin was discussed based on IR spectra.

A series of CeO 2 /SiO 2 mesostructured composite materials was synthesized by sol–gel process using Pluronic P123 as template, tetraethylorthosilicate as silica source and hexahydrated cerium nitrate as precursor under acid condition. The as-synthesized materials with Ce/Si molar ratio ranging from 0.03 to 0.3 were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), laser Raman spectroscopy (LRS), and N 2 adsorption. Characterization revealed that all samples possess ordered hexagonal mesoporous structure similar to SBA-15 and possess high surface area, large pore volume and uniform pore size. The fact that cerium species are present as highly dispersed CeO 2 nanocrystals in hexagonal matrix was confirmed by XRD combined with high-resolution TEM and selected area electron diffraction (SAED) analysis. Introduction of ceria to silica matrix can cause a distortion of hexagonal ordering structure and decrease pore diameter and increase the wall thickness of mesopores. Moreover, it can be found that this sol–gel route is a feasible, effective and simple method for templating synthesis of CeO 2 /SiO 2 composite materials.

The pure-form zeolites (A and X) were synthesized by applying a two-stage method during hydrothermal treatment of fly ash prepared initial Cu and Zn gel. The difference of adsorption capacity of both synthesized zeolites was assessed using Cu and Zn as target heavy metal ions. It was found that adsorption capacity of zeolite A showed much higher value than that of zeolite X. Thus, attention was focused on investigating the removal performance of heavy metal ions in aqueous solution on zeolite A, comparing with zeolite HS (hydroxyl-solidate) prepared from the residual fly ash (after synthesis of pure-form zeolite A from fly ash) and a commercial grade zeolite A. Batch method was used to study the influential parameters of the adsorption process. The equilibrium data were well fitted by the Langmuir model. The removal mechanism of metal ions followed adsorption and ion exchange processes. Attempts were also made to recover heavy metal ions and regenerate adsorbents.

Synthesis of pure-form zeolite A were investigated using four concentrations of NaOH solution to dissolve Si source form fly ash, and with the addition of Al source, to prepare initial gel. Experimental results demonstrated, for two-stage method, that NaOH concentrations in initial gel played an important role in synthesis of pure-form zeolite A using fly ash as raw materials. Generally, pure-form zeolite A could be synthesized when following conditions were used: NaOH concentrations, 1.67, 5 and 6.67 M; the synthesis temperature, 100 degrees C; the corresponding crystallization time, 340, 250 and 190 min. However, a mixture phases of zeolites A and X were obtained at the condition of 3.33 M NaOH solution during various crystallization times. It was found that the higher NaOH concentration was used, the shorter crystallization time of zeolite A was required and the narrower particle size distribution of zeolite A was achieved. In addition, zeolite A submicron-crystals were first synthesized from fly ash using two-stage method in our study.

Mesoporous silica materials with a centered rectangular symmetry (cmm) have been synthesized through a facile direct-templating method using tetraethylorthosilicate (TEOS) and amphiphilic block co-polymers Pluronic P123 under acidic conditions. The amino groups have been grafted to as-synthesized mesoporous silica by [1-(2-amino-ethyl)-3-aminopropyl]trimethoxysilane (AAPTS). Thus obtained amino-functionalized mesoporous silica (denoted as NN-silica) was used for sequestration of Cr(VI) from aqueous solution. After sequestration of Cr(VI), the sample was denoted as Cr(VI)-silica. The parent mesoporous silica, NN-silica and Cr(VI)-silica were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and N(2) adsorption-desorption isotherms. XRD and TEM results confirm that the structure of these samples is centered rectangular symmetry (cmm). N(2) adsorption-desorption isotherms show that there is a remarkable decrease in surface area and pore volume for NN-silica (S(BET)=54.5 m(2)g(-1), V(P)=0.09 cm(3)g(-1)) and Cr(VI)-silica (S(BET)=53.2 m(2)g(-1), V(P)=0.07 cm(3)g(-1)) compared to the parent mesoporous silica (S(BET)=444.0 m(2)g(-1), V(P)=0.71 cm(3)g(-1)). The BJH desorption average diameter of NN-silica, Cr(VI)-silica and the parent mesoporous silica is 4.40 nm, 4.07 nm and 5.11 nm, respectively. The results reveal the channels of as-synthesized mesoporous silica are essentially grafted with abundant amino groups and loaded with Cr(VI). The adsorption experiment results show that the functionalized mesoporous silica materials possess an increased Cr(VI) adsorption capacity and the maximum Cr(VI) loadings at 25, 35 and 45 degrees C can reach 2.28, 2.86 and 3.32 mmol/g, respectively.

Bioelectrochemical system (BES) coupled upflow anaerobic sludge blanket (UASB) was developed for the removal of recalcitrant pollutants but lack of a comprehensive study. Thus in this study an integrated UASB-BES system was operated continuously for 240 d to systematically investigate the feasibility of the enhanced reduction of 2,4-dinitrochlorobenzene (DNCB), with the key operation parameters, the system stability as well as the microbial biodiversity emphasized. The results indicate that high voltage supplied had a positive effect on DNCB reduction but a negative impact for the overhigh voltage (>1.6 V). The ability to resist shock loading was strengthened in the UASB-BES system in comparison with the control UASB system. High-throughput sequencing analysis suggested that the enhanced reduction of DNCB in UASB-BES could be attributed to higher diversity and the enrichment of reduction-related species, potential electroactive species and fermentative species. Both DNCB removal and dechlorination gradually increased with the increase of operation time, indicating the improved performance of the coupled UASB-BES system. The heatmap visualized only slight differences in the microbial community during long-term operation, indicating the stability of the microbial community. The observed efficient and stable performance highlights the potential for long-term operation and full-scale application of the UASB-BES coupled system particularly for highly recalcitrant pollutants removal.

The first example to access ortho iodinated phenols using cyclic hypervalent iodine(iii) reagents through palladium(ii) catalyzed C–H activation has been developed via weak coordination. The reaction showed excellent regioselectivity, reactivity and good functional group tolerance. A unique mechanism was proposed.

The present work reports preparation of ordered mesoporous carbon (OMC) film supported on a graphite fiber as a new type of solid-phase microextraction (SPME) fiber for determination of benzene series from aqueous media. The strategy for the supported OMC film preparation was combined dip-coating technology with solvent evaporation-induced self-assembly (EISA) approach. A graphite fiber was immersed in an ethanol solution containing phenolic resin and Pluronic triblock copolymer. Upon solvent evaporation and subsequent pyrolysis under 700 °C, the phenolic resin and the surfactant self-assembled on the surface of the graphite fiber to form smooth OMC film. X-ray diffraction (XRD), transmission electron microscopy (TEM) and nitrogen isothermal adsorption results indicate that the resultant OMC film possesses well-ordered two dimensional hexagonal mesostructure with pore diameters of 4.5 nm and BET surfaces of 630 m(2)/g. Scanning electron microscopy (SEM) studies show the supported OMC film with thickness at 8.5 μm is continuous and defect-free. The SPME efficiency of the OMC fiber was evaluated by analysis of five benzene series (benzene, toluene, ethylbenzene, p-xylene and m-xylene) from water samples by gas chromatography-flame ionization detection (GC-FID). The analysis results indicate that the prepared OMC fiber has wide linear ranges (0.5-500 μg/L), low detection limits (0.01-0.05 μg/L) and good repeatabilities (4.0-5.8% for one fiber, 2.9-8.7% for fiber-to-fiber). Compared with commercial counterparts, the OMC fiber exhibits improved extraction efficiency for benzene series and PAHs.

A case study is conducted at Jilin Institute of Chemical Technology to investigate the development and characteristics of its interdisciplinary specialty construction program in Materials Science and Engineering. It is hoped that our findings will be helpful to other general engineering colleges as education universities in their efforts to develop interdisciplinary programs.

The effects of synthesis parameters on the property of Ce-ZSM-5 zeolite membrane grown onto porous α-alumina supports were investigated. The zeolite membranes synthesized were characterized by XRD, DTA/TG, FT-IR, SEM, EDS and single gas permeation. Orthogonal test indicate, aging at lower temperature and longer stirring time were preferred for Ce-ZSM-5 zeolite membrane. Lower alkalinity and higher Ce 2 O 3 /SiO 2 favor the formation of pure Ce-ZSM-5 structure. Higher alkalinity and lower SiO 2 /Ce 2 O 3 , impurities such as quartz and cerium oxide, which hinder the Ce-ZSM-5 formation were easily produced. Under optimum synthesis conditions, the permeances for H 2 , N 2 , CH 4 , CO 2 were 4.73 × 10 −6 , 1.56 × 10 −6 , 1.51 × 10 −6 and 1.36 × 10 −6 mol/m 2 s Pa, respectively; the ideal selectivity of membrane at room temperature for H 2 /CO 2 , H 2 /N 2 , H 2 /CH 4 were 3.13, 3.03, 3.48, respectively.

A new method for the preparation of γ-alumina membranes from aluminium chloride was investigated in this paper. Boehmite sol was synthesized by an anionic exchange method, which could offer OH − -ion and simultaneously remove Cl − -ion. Boehmite sols were then deposited on the inner surface of the hollow fiber supports by a filtration technique. The thermal evolution, phase transformation, structure, morphology and pore size distribution of the γ-alumina membranes were characterized by thermogravimetric analysis (TGA), differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and nitrogen isothermal adsorption measurement. SEM images showed that the membranes were defect-free. Gas permeability tests suggested that the obtained membranes possessed gas selectivity, and its separation factor for H 2 /N 2 and H 2 /CH 4 were 3.31 and 2.25 at 0.1 MPa, respectively. The most concentrative pore diameter, pore volume and specific surface area of an unsupported membrane calcinated at 600 °C were 3.7 nm, 0.18 ml/g and 176.9 m 2 /g, respectively.

Key steps of the new synthesis of (6-amino-2-chloro-3-fluorophenyl)methanol (V) presented is the stepwise palladium-catalyzed halogenation which gives the product in an overall yield of 18% over four steps.

Nanosized ZSM-5 zeolite was successively synthesized in the absence of organic template by hydrothermal method. About 15 nm ZSM-5 zeolite was synthesized at 180 °C for 24 h after stirring at high speed and aging in the synthesis mixture with the molar composition of 12Na2O : 100SiO2 : 2Al2O3 : 2500 H2O. X-ray diffraction (XRD) confirmed ZSM-5 crystal phase. Transmission electron microscopy (TEM) showed that ZSM-5 zeolite crystal sizes are about 15 nm. The electron diffraction spectroscopy (EDS) shows nanosized ZSM-5 zeolites chemical element compound. Fourier transform infrared (FTIR) analysis further showed that they are pentacyclic with typical absorption summit of ZSM-5 at about 550 cm− 1. Differential thermal analysis and thermogravimetry analysis (DTA/TG) showed that, at room temperature to 1073 K, nanosized ZSM-5 mass loss is 5.836%.

Aerobic granules were successfully cultivated in a sequencing batch reactor (SBR), using a single bacterial strain Rhizobium sp. NJUST18 as the inoculum. NJUST18 presented as both a good pyridine degrader and an efficient autoaggregator. Stable granules with diameter of 0.5–1 mm, sludge volume index of 25.6 ± 3.6 mL g−1 and settling velocity of 37.2 ± 2.7 m h−1, were formed in SBR following 120-day cultivation. These granules exhibited excellent pyridine degradation performance, with maximum volumetric degradation rate (Vmax) varied between 1164.5 mg L−1 h−1 and 1867.4 mg L−1 h−1. High-throughput sequencing analysis exhibited a large shift in microbial community structure, since the SBR was operated under open condition. Paracoccus and Comamonas were found to be the most predominant species in the aerobic granule system after the system had stabilized. The initially inoculated Rhizobium sp. lost its dominance during aerobic granulation. However, the inoculation of Rhizobium sp. played a key role in the start-up process of this bioaugmentation system. This study demonstrated that, in addition to the hydraulic selection pressure during settling and effluent discharge, the selection of aggregating bacterial inocula is equally important for the formation of the aerobic granule.

This halogenation protocol requires no air- and moisture-proof conditions and is successfully applied even to the chlorination of carbamate-protected estrone.

A room-temperature Pd(II)-catalyzed regioselective chlorination reaction has been developed for a facile one-pot synthesis of a broad range of 2-chlorophenols. The reaction demonstrates an excellent regioselectivity and reactivity for C–H chlorination. This reaction represents one of the rare examples of mild C–H functionalization at ambient temperature.

Biodegradation of pyridine by a novel bacterial strain, Rhizobium sp. NJUST18, was studied in batch experiments over a wide concentration range (from 100 to 1,000 mg l(-1)). Pyridine inhibited both growth of Rhizobium sp. NJUST18 and biodegradation of pyridine. The Haldane model could be fitted to the growth kinetics data well with the kinetic constants μ* = 0.1473 h(-1), K s = 793.97 mg l(-1), K i = 268.60 mg l(-1) and S m = 461.80 mg l(-1). The true μ max, calculated from μ*, was found to be 0.0332 h(-1). Yield coefficient Y X/S depended on S i and reached a maximum of 0.51 g g(-1) at S i of 600 mg l(-1). V max was calculated by fitting the pyridine consumption data with the Gompertz model. V max increased with initial pyridine concentration up to 14.809 mg l(-1) h(-1). The q S values, calculated from [Formula: see text], were fitted with the Haldane equation, yielding q Smax = 0.1212 g g(-1) h(-1) and q* = 0.3874 g g(-1) h(-1) at S m' = 507.83 mg l(-1), K s' = 558.03 mg l(-1), and K i' = 462.15 mg l(-1). Inhibition constants for growth and degradation rate value were in the same range. Compared with other pyridine degraders, μ max and S m obtained for Rhizobium sp. NJUST18 were relatively high. High K i and K i' values and extremely high K s and K s' values indicated that NJUST18 was able to grow on pyridine within a wide concentration range, especially at relatively high concentrations.

The heterofullerenes C59N and C69N and their dimers are examined by the intermediate neglect of differential overlap (INDO/1 and INDO/S) models. The results confirm the stability of the (C59N)2 and (C69)2 (C2h) isomers with a 6–6 closure fusion link between the two monomers. The nearest neighbor C of nitrogen, at the hexagon–hexagon fusion in C59N and in C69N where the N replaces one C in the pentagon of the fullerene has the largest electronic spin density, and this is where the two radicals of C59N or C69N link to form dimers. Also the dimers readily dissociate to free radical monomers to react regioselectively with other reagents. The electronic spectra of the radicals are similar to those of the dimers, which suggest essentially identical electronic structures. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 78: 422–436, 2000

The novel and scalable ortho-chlorination/bromination reaction can be applied for the synthesis of a broad range of arene chlorides and bromides.

A combined zero valent iron (ZVI) and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene (DNCB)-containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated. After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene (DACB). The ratio of BOD5/COD increased from 0.005 +/- 0.001 to 0.168 +/- 0.007, while EC(50, 48 hr) (V/V) increased from 0.65% to 5.20%, indicating the enhancement of biodegradability and reduction of acute toxicity with the pretreatment by ZVI. DACB was further dechlorinated to m-phenylenediamine during the anaerobic process using methanol as electron donor, with EC(50, 48 hr) increasing from 5.20% to 48.2%. After the subsequent anaerobic-aerobic process, m-phenylenediamine was degraded completely, with effluent COD of 67.5 +/- 10.8 mg/L. This effluent of the subsequent anaerobic-aerobic process was not toxic to zebrafish. The combined ZVI and anaerobic-aerobic process offers bright prospects for the treatment of chlorinated nitroaromatic compound-containing wastewater.

A combined zero-valent iron (ZVI) reduction and Fenton oxidation process was tested for the pretreatment of 2,4-dinitroanisole (DNAN) producing wastewater. Operating conditions were optimized and overall performance of the combined process was evaluated. For ZVI process, almost complete reduction of nitroaromatic compounds was observed at empty bed contact time (EBCT) of 8 h. For Fenton process, the optimal pH, H 2 O 2 to Fe(II) molar ratio, H 2 O 2 dosage and hydraulic retention time (HRT) were found to be 3.0, 15, 0.216 mol/L and 5 h, respectively. After pretreatment by the combined ZVI-Fenton process under the optimal conditions, aromatic organic compound removal was as high as 77.2%, while the majority of COD remained to be further treated by sequent biological process. The combined anaerobic-aerobic process consisted of an anaerobic baffled reactor (ABR) and a moving-bed biofilm reactor (MBBR) was operated for 3 months, fed with ZVI-Fenton effluent. The results revealed that the coupled ZVI-Fenton-ABR-MBBR system was significantly efficient in terms of correcting the effluent's main parameters of relevance, mainly aromatic compounds concentration, COD concentration, color and acute toxicity. These results indicate that the combined ZVI-Fenton process offers bright prospects for the pretreatment of wastewater containing nitroaromatic compounds.

Glucose transporters are essential for metabolism of glucose in cells of diverse organisms from microbes to humans, exemplified by the disease-related human proteins GLUT1, 2, 3 and 4. Despite rigorous efforts, the structural information for GLUT1–4 or their homologues remains largely unknown. Here we report three related crystal structures of XylE, an Escherichia coli homologue of GLUT1–4, in complex with d-xylose, d-glucose and 6-bromo-6-deoxy-d-glucose, at resolutions of 2.8, 2.9 and 2.6 A, respectively. The structure consists of a typical major facilitator superfamily fold of 12 transmembrane segments and a unique intracellular four-helix domain. XylE was captured in an outward-facing, partly occluded conformation. Most of the important amino acids responsible for recognition of d-xylose or d-glucose are invariant in GLUT1–4, suggesting functional and mechanistic conservations. Structure-based modelling of GLUT1–4 allows mapping and interpretation of disease-related mutations. The structural and biochemical information reported here constitutes an important framework for mechanistic understanding of glucose transporters and sugar porters in general. A study of X-ray crystal structures of the Escherichia coli xylose transporter XylE, which is a bacterial homologue of the human glucose transporters GLUT1–4, complexed with glucose and its analogues yields a framework for understanding the molecular mechanism by which membrane proteins transport glucose and other sugars across cell membranes. Proteins that transport glucose across cellular membranes are essential for glucose metabolism in many organisms, from microbes to mammals. This Article reports three X-ray crystal structures of XylE — an Escherichia coli homologue of the GLUT family of human proteins — in complex with D-xylose, D-glucose and 6-bromo-6-deoxy-D-glucose. Structure-based modelling of GLUT1–4 enabled the authors to map known disease-related mutations, and the structural and biochemical information reported here provides a framework for understanding the molecular mechanism by which membrane proteins transport glucose and other sugars.

A one-pot method is developed for the synthesis of functionalized quinolines from easily accessible starting materials at ambient temperature.

Recently, inorganic nanoparticles blended within polymeric membranes have shown improved antifouling performance in wastewater treatment. However, agglomeration of nanoparticles remains as one of the major obstacles for generating a uniform surface. In this study, a new method for in situ preparation of Al-containing PVDF ultrafiltration membranes to improve the dispersion of nanoparticles is reported. The strategy of this method is to combine sol–gel process with traditional immersion precipitation process. Al sol was synthesized by the addition of anionic exchange resin in N,N-dimethylformamide (DMF) solvent containing aluminum chloride. Homogeneous Al-containing PVDF casting solution was then obtained by dissolving PVDF polymer in the Al sol. The membrane formation mechanism was investigated by precipitation kinetics and morphology. Results indicate that the addition of Al species can accelerate phase inversion of casting solution. Scanning electron microscopic images show that a typical transition from sponge-like structure to finger-like structure occurred with increasing Al species content. The existence and dispersion states of Al species in the resultant membrane matrix were further examined by transmission electron microscope and X-ray photoelectron spectrometer. The results indicate the Al species nanoparticles were well dispersed throughout PVDF matrix. Dynamic BSA fouling resistance experiments demonstrate the Al-containing PVDF membranes possess improved separation performances over the pure PVDF membranes.

Bioelectrochemical system (BES) for recalcitrant p-nitrophenol (PNP) removal was investigated in this study. Effective removal of PNP at rates up to 9.14 ± 0.48 mol m(-3)d(-1) was achieved at an energy consumption as low as 0.010 ± 0.002 kWh mol(-1) PNP. PNP removal rate was enhanced with negative cathode potential, increased influent PNP concentration and shortened hydraulic retention time (HRT). Although the coulombic efficiencies at the anode did not exceed 40%, coulombic efficiencies for PNP removal at the cathode were above 70% at various cathode potentials. Compared with conventional anaerobic process, the cosubstrate dosage in BES was significantly reduced due to the high coulombic efficiencies at the cathode. p-Aminophenol (PAP) was identified as the dominant product of PNP reduction at the abiotic graphite cathode of BESs. This study demonstrated that the BES had a potential for efficient removal of nitrophenol pollutants from wastewater.

A membrane-based gas absorption (MGA) process was evaluated for the removal of volatile organic compounds (VOCs) based on C6H6/N2 mixture. The absorption of C6H6 from a C6H6/N2 mixture was investigated using a hydrophobic polypropylene hollow fiber membrane contactor and the aqueous solution of N-formyl morpholine (NFM) as absorbent. The effects of various factors on the overall mass transfer coefficient was investigated. The experimental results showed that the removal efficiency of C6H6 could reach 99.5% in present studied system. A mathematical model based on resistance-in-series concept was presented to predict the value of overall mass transfer coefficient. The average error between the predicted and experimental values is 7.9%. In addition, conventional packed columns for VOCs removal was also evaluated for comparison.

A modified anoxic/oxic-membrane bioreactor has been applied to the denitrification of a high strength nitrate waste (about 3600 mg/L nitrate-N) generated from an initiating explosive factory. Nitrate removal efficiency and nitrite accumulation in the treated water were investigated under various conditions set by several factors including the type of carbon source used, ratios of carbon to nitrogen, pH and hydraulic retention times (HRTs). The results of the preliminary experiments, which were carried out in parallel CSTR systems, demonstrated that sodium acetate had shown the best performance as the external carbon source. The optimal reaction parameters in the anoxic/oxic-membrane bioreactor were pH 7.5–8.5, C/N 1.56 and HRT 30 h, with over 99.9% of nitrate removed and without accumulation of nitrite. Explicitly high average-specific denitrification rate of 324 mg NO3−-N/g VSS/h could be attained under these conditions. The aerobic process and membrane module used subsequently could remove the residual COD, excessive biomass and soluble microbial products generated during the denitrification process.

Biological degradation of 2,4,6-trinitrophenol (TNP) by Rhodococcus sp.NJUST16 in mineral salt medium was investigated in shake-flask experiments at pH of 7.0 and 30°C, over a wide range of initial TNP concentration (20–800 mg l −1 ). The TNP was observed to be the inhibitory compound. For the studied concentration range, Haldane's model could be fitted to the growth kinetics data well with the kinetic constants μ max = 0.2362 h −1 , K s = 9.9131 mg l −1 and K i = 362.7411 mg l −1 . Further, the variation of observed yield coefficient Y with initial TNP concentration and the decay coefficient were investigated. It is our view that the above information would be useful for modeling and designing the units treating TNP-containing wastewaters.

This paper reports on a new method for the preparation of mesoporous silica membranes on alumina hollow fibers. A surfactant-silica sol is filled in the lumen of an alpha-alumina hollow fiber. The filtration technique combined with an evaporation-induced self-assembly (EISA) process results in the formation of a continuous ordered mesoporous silica layer on the outer side of alpha-alumina hollow fibers. X-ray diffraction (XRD), transmission electron microscopy (TEM), and nitrogen isothermal adsorption measurements reveal that these membranes possess hexagonal (P6mm) mesostructures with pore diameters of 4.48 nm and BET surfaces of 492.3 m(2) g(-1). Scanning electron microscopy (SEM) studies show that the layers are defect free and energy-dispersive spectroscopy (EDS) mapping images further confirm the formation of continuous mesoporous silica layer on the outer side of alpha-alumina hollow fibers. Nitrogen and hydrogen permeance tests show that the membranes are defect free.

Bactericide wastewater (BIW) contains isothiazolin-ones, high salinity, toxicity and non-biodegradable organic concentrations. In order to enhance biodegradable capacity, chemical coagulation and electrochemical oxidation were applied to pretreatment processes. FeSO4·7H2O, pH 12 and 20 mmol/l were determined as optimal chemical coagulation condition; and 15 mA/cm2 of current density, 10 ml/min of flow rate and pH 7 were chosen for the most efficient electrochemical oxidation condition at combined treatment. The wastewater which consisted mainly of isothiazolin-ones and sulfide was efficiently treated by chemical coagulation and electrochemical oxidation. The optimal pretreatment processes showed 60.9% of chemical oxygen demand (COD), 99.5% of S2− and 96.0% of isothiazolin-ones removal efficiency. A biological treatment system using membrane bioreactor (MBR) adding powder-activated carbon (PAC) was also investigated. COD of the wastewater which was disposed using a MBR was lower than 100 mg/l.