Fabrication of poly(vinylidene fluoride) membrane via thermally induced phase separation using ionic liquid as green diluent

Ionic liquid(IL), 1-butyl-3-methylimidazolium hexafluorophosphate([BMIM]PF6) as a new and environmentally friendly diluent was introduced to prepare poly(vinylidene fluoride)(PVDF) membranes via thermally induced phase separation(TIPS). Phase diagram of PVDF/[BMIM]PF6 was measured. The effects of polymer concentration and quenching temperature on the morphologies, properties, and performances of the PVDF membranes were investigated. When the polymer concentration was 15 wt%, the pure water flux of the fabricated membrane was up to nearly 2000 L·m~(-2)·h~(-1), along with adequate mechanical strength. With the increasing of PVDF concentration and quenching temperature, mean pore size and water permeability of the membrane decreased. SEM results showed that PVDF membranes manufactured by ionic liquid(BMIm PF6) presented spherulite structure. And the PVDF membranes were represented as β phase by XRD and FTIR characterization. It provides a new way to prepare PVDF membranes with piezoelectric properties.     

以L-谷氨酰胺-铜（Ⅱ）配合物为供体酶法制备茶氨酸

A novel method for enzymatic synthesis of L-theanine using copper（Ⅱ）-L-glutamine［Cu（Gln）₂］as donor substrate was proposed.The structure of Cu（Gln）₂ was identified by infrared spectrum analysis and its stability was also investigated under the reaction conditions.The enzymatic synthesis of L-theanine catalyzed by γ-glutamyltranspeptidase was carried out by using Cu（Gln）₂ and L-glutamine as donor substrate respectively,and the product yield and conversion rate of donor substrate were compared under the conditions of different ratios of donor and acceptor.The results showed that the transpeptidation reaction could be effectively enhanced by using Cu（Gln）₂ as donor substrate.The conversion rate of donor would increase by 51.5%,44.9% and 27.1% under different reaction conditions,compared to that using L-Gln as donor substrate.When the molar ratio of donor to acceptor was 6∶100,a higher donor conversion of 71.3% was obtained.     

Preparation of an amphoteric flocculant having both high polymer content and low viscosity and its polymerization kinetics

It is not easy for liquid cationic flocculant diallyldimethyl-ammonium chloride(DM) homopolymer to simultaneously exhibit both low viscosity and high polymer content, which limited its application in offshore oilfield.In this paper, sodium allylsulfonate(XS) and sodium formate were used in the aqueous solution polymerization of DM.An amphoteric flocculant(PDMXS) with the properties of high polymer content(about 55 wt%) and low viscosity(efflux time measured by an Apply 4 viscometer was less than 100 s) was prepared.The optimum reaction conditions were identified as follows: the mass ratio of XS/DM was 10 wt%, the concentration of sodium formate was 2000 mg·L~(-1), reaction temperature was 55 ℃, the concentration of KPS was 0.5 wt% and the reaction time was 4 h.The polymerization kinetics was discussed.The results showed that R_p∝ [M]~(1.97)[I]~(0.68)[CTA]~(0.71) and the apparent activation energy was 72.55 kJ·mol~(-1).     

Extraction Equilibria of Trimellitic and [ 1,1′-Biphenyl]-2,2′-dicarboxylic Acid with 1-Octanol, 50%TBP,and 10%TRPO in Kerosene

To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate （TBP） in kerosene, and 10% trialkylphosphine oxide （TRPO） in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio.     

Conductivities of AlCl3/Ionic Liquid Systems and Their Application in Electrodeposition of Aluminium

Solubilities and conductivities of anhydrous AlCl3 in six kinds of ionic liquids (ILs) were measured. Among the six kinds of ILs [bmim]Cl, [bmim]Br, [bmim]BF4, [bmim]PF6, [emim][EtSO4] and [bmim][HSO4], anhydrous AlCl3 could be dissolved in the first five kinds but was hardly dissolved in [bmim][HSO4]. The results showed that the nominal solubilities of AlCl3 in ILs increased in the order of [bmim][HSO4] < [bmim]PF6 < [emim][EtSO4] < [bmim]BF4 < [bmim]Cl < [bmim]Br. Conductivities of the AlCl3/ILs systems depended apparently on the nominal molar ratio of AlCl3 to ILs. The conductivities of AlCl3/[bmim]Cl, AlCl3/[bmim]Br and AlCl3/[bmim]PF6 systems had a similar tendency as a function of the nominal molar ratio, that is, as the molar ratio was increased, conductivities increased first and then decreased, with the maximum conductivity obtained at approximately 0.9:1, 1.0:1 and 0.5:1, respectively. Conductivities of the AlCl3/[bmim]BF4 exhibited a dentate change and decreased with the molar ratio of AlCl3 to [bmim]BF4 increasing in general. With the increasing of the anhydrous AlCl3 amount in [emim][EtSO4], conductivity of AlCl3/[emim][EtSO4] monotonically decreased. AlCl3/[bmim]Cl system was chosen as the electrolyte for the electrodeposition of Al. Preliminary experimental results showed that dense, adherent and homogeneous Al coatings could be electrodeposited on stainless steel by means of constant potential technique and the surface coverage was quite satisfactory.     

硅溶胶/苯乙烯-丙烯酸酯共聚物无机-有机杂化水分散液的制备和表征

A stable silica sol with 3-5 nm in diameter, which can form homogeneous film without crack, was prepared and characterized. Then, the inorganic-organic hybrid aqueous dispersion composed of such a silica sol and an emulsion of styrene （St） and acrylate （Ac） copolymer was prepared and the hybrid effect between the silica sol and poly（St-co-Ac） was observed by Fourier transform infra-red （FT-IR） spectroscope. The toughness of the film prepared by this kind of hybrid aqueous dispersion was excellent, as it was enhanced appreciably by commixing with a small amount of poly（St-co-Ac） emulsion. Some amino-polysiloxane modified hybrid aqueous dispersions were also prepared and the properties of the modified dispersions and their films were investigated. The experimental results showed that the film prepared with such an amino-polysiloxane modified hybrid dispersion exhibited excellent hydrophobicity and low surface energy after heat treatment for 1.5 h, during which the formation of the graft copolymer was observed. The surface energy of this film decreases as a result of the enrichment of siloxane segments on the film surface.     

离子液体；石油沥青质的新型溶剂

The dissolution of petroleum asphaltenes with ionic liquids is studied for the first time. The results show that the ionic liquids could be used as novel solvents for asphaltenes. The important parameters governing the ability of ionic liquids for dissolution of asphaltenes are discussed. It is found that, the ionic liquids based on the cations containing a conjugated aromatic core or the anions which are strong hydrogen bond acceptors are most effective, whereas the ionic liquids containing ＇non coordinating＇ anions such as [BF4]^- and [PF6]^- are nonsolvents for asphaltenes. Increase in the effective anion charge density enhances the ability of ionic liquids to break the extensive asphaltene associations and thus enhances the solubility of asphaltenes in the ionic liquid. The dissolution ability of ionic liquid decreases apparently with increasing the substituted alkyl chain length of its cationic head ring. Temperature is found to play an important role on dissolution of asphaltenes, and the dissolution can be significantly imoroved bv microwave heatinz.     

Determination and Correlation of Solubilities of Four Novel Benzothiazolium Ionic Liquids with PF6^- in Six Alcohols

Four novel benzothiazolium ionic liquids with 6PF- （[C1Bth][PF6], [C4Bth][PF6], [C5Bth][PF6] and [C6Bth][PF6]） were synthesized, and the rang of their melting points were determined between 358.35 K-424.05 K. The relationship of their melting points and the length of the straight alkyl chain on cation reflected‘S’ type ten-dency. Then, the solubilities of the four ionic liquids in six lower alcohols （methanol, ethanol, 1-propanol, 2-propanol, 1-butanol and 2-methyl-1-propanol） were measured in the temperature rang of 253.15-383.15 K at at-mospheric pressure with static analytical method, respectively. It was found that [C6Bth][PF6] in all investigated ionic liquids had the largest solubility in six alcohols and the solubility of [C4Bth][PF6] in methanol was very sensi-tive for temperature in 313.15-333.15 K, which was so-called “temperature-sensitivity”. This feature is of great significance to their application of catalyzing reaction or extraction process, and makes the recovery and reuse of ionic liquids （ILs） become easier. Moreover, the experimental solubility data were correlated with the modified Apelblat equation andλh equation, respectively. It was found that the result of correlation using two divided tem-perature ranges was better than that of using the whole temperature range.     

以葡辛胺为拆分剂拆分酮基布洛芬

The process of resolution of racemic ketoprofen using n-octyl-d-glucamine as an optical resolution agent was investigated. The process consists of preparation of the diastereomer salt of ketoprofen with n-octyl-d-glucamine, liberation of S-（＋）-ketoprofen from its diastereomer salt and recovery of the remaining ketoprofen and n-octyl-d- glucamine. The suitable conditions for preparation of the diastereomer salt were methanol and ethyl acetate （1：1 by volume） as the solvent, the ratio of solvent volume to ketoprofen mass at 8 ml：1 g, and the molar ratio of ketoprofen to n-octyl-d-glucamine at 1：1. The preferred approach to liberate S-（＋）-ketoprofen from its diastereomer salt was alkali dissolution, acid adjustment and ethyl acetate extraction. Racemization of the recovered ketoprofen could be achieved by reacting the recovered ketoprofen with 10% NaOH at 507kPa for 6h. The recovered n-octyl-d- glucamine could be refined by acid dissolution and alkali adjustment. S-（＋）-ketoprofen can be obtained with high optical purity and yield, showing that the present process is a practical and efficient one which can be used in industrial scale for preparation of S-（＋）-ketoprofen.     

An Intermediate-temperature H2S Fuel Cell with a Li2SO4-based Proton-conducting Membrane

A laboratory-scale intermediate-temperature H2S fuel cell with a configuration of H2S, （metal sulfide-based composite anode）/Li2SO4＋Al2O3/（NiO-based composite cathode）, air was developed and studied for production of power and for desulfurization of a fuel gas process stream. The cell was run at typical temperature （600-650℃） and ambient pressure, but its electrochemical performance may be limited by electrolyte membrane thickness. The membrane and its performance in cell have been characterized using scanning electron microscope （SEM） and electrochemical impedance spectrum （EIS） techniques. Composite anodes based on metal sulfides, Ag powder and electrolyte behaved well and stably in H2S stream, and composite cathodes based mainly on nickel oxide, Ag powder and electrolyte had superior performance to Pt catalyst. The maximum power density of up to 70mW.cm^-2 and current density of as high as 250mA.cm^-2 were obtained at 650℃. However, the long-term cell stability remains to be investigated.     

Preparation of TiO2 Nanoparticles Coated Cotton Fibers at Low Temperature and Their Photocatalytic Activity

TiO_2 nanoparticles coated cotton fiber composite was successfully prepared by using a sol-gel method at low temperature(about 100℃) using tetrabutyl-titanate [Ti(OBu)_4] as raw material.The preparation of the TiO_2 colloid and the composite were described.The properties of resulting materials were characterized by SEM and XRD,the photocatalytic degradation performance was tested using methylene blue(MB) as the target pollutant in aqueous solution.The results showed that the amorphous TiO_2 nanoparticles were distributed evenly on the outer surfaces of cotton fibers,which shows efficient photocatalytic properties when exposed to UV light,the degradation rate of MB reached 95.35% under the conditions of catalyst dosage 2.5 g/L,MB concentration 50 mg/L,irradiation time 120 min,and pH 10,and the photocatalytic activity of TiO_2/cotton fibers remained above 90% of its activity as-prepared after being used four times,the degradation rate of MB could reach 88.78% when irradiation time was 120 min.The photocatalytic degradation of MB could be properly described by the first-order kinetic law.By comparison of the removal rates of MB with and without UV light,it could be affirmed that the disappearance of MB was due to photodegradation rather than adsorption on cotton fibers.     

水对前驱物催化合成二噁英的影响

The effect of water on the formation of polychlorinated dibenzo-p-dioxins（PCDDs）and dibenzofurans（PCDFs）from precursor was investigated by the experiments with a fixed-bed reactor：the reactant mixture with different moisture of 123-TrCB and CuCl₂ for metal-catalyzed formation,that of 123-TrCB and fly ash for surface-catalyzed formation. The experimental results show that the water has the following effects：first,suppressing the formation of PCDD/Fs as less its yield;second,inhibiting chlorination reaction as lower chlorination degree;third,having different effect on PCDDs and PCDFs as lower ratio of PCDFs/PCDDs.The explanations might be the competitive adsorption of water vapor with TrCB on active sites of the fly ash and the catalysis of copper was weakened chloride because of its oxidative conversion to copper oxide.     

Lipase-catalyzed Synthesis of Caffeic Acid Phenethyl Ester in Ionic Liquids： Effect of Specific Ions and Reaction Parameters

Caffeic acid phenethyl ester（CAPE） is a rare, naturally occurring phenolic food additive. This work systematically reported fundamental data on conversion of caffeic acid（CA）, yield of CAPE, and reactive selectivity during the lipase-catalyzed esterification process of CA and phenylethanol（PE） in ionic liquids（ILs）. Sixteen ILs were selected as the reaction media, and the relative lipase-catalyzed synthesis properties of CAPE were measured in an effort to enhance the yield of CAPE with high selectivity. The results indicated that ILs containing weakly coordinating anions and cations with adequate alkyl chain length improved the synthesis of CAPE. [Emim][Tf2 N] was selected as the optimal reaction media. The optimal parameters were as follows by response surface methodology（RSM）： reaction temperature, 84.0 °C; mass ratio of Novozym 435 to CA, 14︰1; and molar ratio of PE to CA, 16 ︰ 1. The highest reactive selectivity of CAPE catalyzed by Novozym 435 in [Emim][Tf2 N] reached 64.55%（CA conversion 98.76% and CAPE yield 63.75%, respectively）. Thus, lipase-catalyzed esterification in ILs is a promising method suitable for CAPE production.     

Photodegradation of benzothiazole ionic liquids catalyzed by titanium dioxide and silver-loaded titanium dioxide

In recent years, ionic liquids(ILs) have been widely used in extraction, synthesis, electrochemistry and other fields.Meanwhile, the environmental impact of ILs has been attracting a lot of attention, and eco-friendly treatment for ILs is becoming a necessary subject. In this study, photocatalytic degradations of benzothiazole ILs catalyzed by titanium dioxide(TiO_2) and silver-loaded titanium dioxide(Ag/TiO_2) were studied for the first time. The degradation of benzothiazole hexafluorophosphate([C4 Bth]PF6) could reach more than 99% within 240 min with the catalysis of TiO_2. To improve catalytic efficiency, Ag/TiO_2 was synthesized and characterized by UV–Vis diffuse reflectance absorption spectra(DRS) and X-ray photoelectron spectroscopy(XPS). The degradation of [C4 Bth]PF6 could reach more than 99% within 120 min in the degradation catalyzed by Ag/TiO_2. The photodegradation products of benzothiazole ILs are composed of inorganic substances or organic substances with simpler structures, which are easier to decompose and less toxic. The degradation system proposed by this study could provide a simple, green,safe, and economical method for the efficient treatment of benzothiazole ILs.     

Effects of Assistant Solvents and Mixing Intensity on the Bromination Process of Butyl Rubber

A slow bromination process of butyl rubber （IIR） suffers from low efficiency and low selectivity （S） of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%（by volume） dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product （xA1s） of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r＆#183;min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed （RPB） reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.     

Peanut Shell Activated Carbon： Characterization,Surface Modification and Adsorption of Pb^2＋ from Aqueous Solution

Metal ion contamination of drinking water and waste water, especially with heavy metal ion such as lead, is a serious and ongoing problem. In this work, activated carbon prepared from peanut shell （PAC） was used for the removal of Pb^2＋ from aqueous solution. The impacts of the Pb25 adsorption capacities of the acid-modified carbons oxidized with HNO3 were also investigated. The surface functional groups of PAC were confirmed by Fourier transform infrared （FTIR） spectroscopy, X-ray photoelectron spectroscopy （XPS）, Boehm titration. The textural properties （surface area, total pore volume） were evaluated from the nitrogen adsorption isotherm at 77 K. The experimental results presented indicated that the adsorption data fitted better with the Langmuir adsorption model. A comparative study with a commercial granular activated carbon （GAC） showed that PAC was 10.3 times more efficient compared to GAC based on Langmuir maximum adsorption capacity. Further analysis results by the Langmuir equation showed that HNO3 [20% （by mass）] modified PAC has larger adsorption capacity of Pb^2＋ from aqueous solution （as much as 35.5 mg·g^-1）. The adsorption capacity enhancement ascribed to pore widening, increased cation-exchange capacity by oxygen groups, and the promoted hydrophilicity of the carbon surface.     

非均相催化一步合成碳酸二苯酯的研究（VI）Sn 的添加量对Pd-Sn催化性能的影响

The compound metal oxide LaxPbyMnzO used as support was prepared by the sol-gel method, and the catalyst in which Pd was used as active component and Sn as co-active component for direct synthesis of diphenyl carbonate (DPC) with heterogeneous catalytic reaction was obtained by co-calcination and precipitation respectively.The catalyst was characterized by XRD, SEM and TEM respectively. The specific surface area of catalysts was measured by ChemBET3000 instrument, and the activity of the catalysts was tested by the synthesis of DPC in a pressured reactor. The results showed that when the co-active component Sn was added by co-calcination method A, its loading content was equal to 14.43% and active component Pd was loaded by precipitation, the yield and selectivity of DPC could reach 26.78% and 99% respectively.     

碳化钨和天然沸石复合材料在水溶液中的电催化活性(英文)

Tungsten carbide and zeolite nanocomposite was prepared by combining a mechanochemical approach with a reduction and carbonization approach,using natural zeolite and ammonia metatungstate as precursors.The sample was characterized by X-ray diffraction and scanning electron microscope.The results showed that the crystal phase of the sample is composed of zeolite,monotungsten carbide and bitungsten carbide.The mass percentage and the crystallite diameter of tungsten carbide change along with the reacted time.Its electrocatalytic activity was measured with a microelectrode system with three electrodes.The results show that its electrocatalytic property is related to its crystal phase and the mass percentage of tungsten carbide,and its electrocatalytic activity is connected with the property of electrolyte,in which it is measured.Synergistic effect between tungsten carbide and zeolite is found during electrocatalysis.     

非均相催化一步合成碳酸二苯酯的研究(VI)Sn的添加方法及添加量对Pd-Sn催化性能的影响

The compound metal oxide Lax Pby Mnz O used as support was prepared by the sol-gel method, and the catalyst in which Pd was used as active component and Sn as co-active component for direct synthesis of diphenyl carbonate (DPC) with heterogeneous catalytic reaction was obtained by co-calcination and precipitation respectively. The catalyst was characterized by XRD, SEM and TEM respectively. The specific surface area of catalysts was measured by ChemBET3000 instrument, and the activity of the catalysts was tested by the synthesis of DPC in a pressured reactor. The results showed that when the co-active component Sn was added by co-calcination method A, its loading content was equal to 14.43% and active component Pd was loaded by precipitation, the yield and selectivity of DPC could reach 26.78% and 99% respectively.     

吡啶类离子液体在类紫罗兰二烯烯丙位氧化中均相与非均相行为

The combination of relatively low-cost ionic liquids, simple copper salt, and terminal oxidant tert-butyl hydroperoxide provided an efficient and environmentally friendly approach to the preparation of ionone-like dienones. Six pyridinium ionic liquids were evaluated in allylic oxidation of α-ionone and β-ionone. The 60%–70% yields of 3-oxo-α-ionone were obtained with 0.02-0.20 mmol of CuCl2&#8226;2H2O as catalyst, 3-5 mmol of tert-butyl hydroperoxide as oxidant and 1 g of [Bpy]PF6 as solvent for 4-20 h at 60°C. The facile recovery and recycle of catalyst were also achieved. More significantly, peculiar phase behaviors of [Bpy]PF6 and [Epy]PF6 offered the catalytic system advantages of homogeneous reaction and heterogeneous separation. Scanning electron microscope (SEM) images of [Bpy]PF6 provided evidences for the behaviors. Transmission electron microscope (TEM) micrographs showed copper salt nanoparticles catalyst formed and stabilized in pyridinium ionic liquids.