Influence of zeolite on electrochemical and physicochemical properties of polyethylene oxide solid electrolyte

A composite polymer electrolyte of polyethyleneoxide-LiBF₄ containing fine particles of zeolite was studied using electrochemical impedance spectroscopy, cyclic voltammetry, differential scanning calorimetry, infrared spectroscopy and scanning electron microscopy. When compared with the polymer electrolyte without zeolite, the specific conductivity of the composite electrolyte film is higher by about two orders of magnitude at room temperature. The increase in specific conductivity is explained as due to increased amorphocity which is reflected in the thermal studies. The nature of the cyclic voltammograms and infrared spectra is discussed.Part of this work was presented at the Electrochemical Society Meeting, Honolulu, Hawai (May 1993).     

Hydrocarbon sorption properties of pure silica MCM-22 type zeolite

The adsorption properties of the MWW compositional end member, ITQ-1, have been explored empirically and via computer simulation using n-hexane, 3-methylpentane, 2,3-dimethylbutane, p-xylene and ethylbenzene as adsorbate probes. n-Hexane and 3-methlypentane diffuse rapidly and both have a sorption limit of four molecules per unit cell, three of which are in the large channel cavities. 2,3-dimethylbutane sorbs more slowly through the 10-ring windows; the limiting three molecules per unit cell are all in the large cavities. The two aromatics adsorb in both channel systems, with p-xylene diffusing rapidly and ethylbenzene more slowly but much faster than 2,3-dimethylbutane. No clear distinction between intra- and extra-crystalline adsorption was observed. Computer modeling indicated distinctions between the two channel systems.     

沸石分子筛吸附性能的测定方法

介绍了沸石分子筛吸附性能常用的测定方法,综述了近年来沸石分子筛吸附性能的研究进展。认为在众多方法中,气相色谱法、智能重量分析技术、频率响应法、分子模拟技术等以其方便有效的优点,是测定沸石分子筛吸附性能的重要手段。     

Thermal and electrochemical properties of cobalt containing Finemet type alloys

This paper presents results concerning the effect of cobalt substitution on bulk (thermal) and surface (electrochemical) properties of Finemet type alloys. Thermal properties of the alloys were determined by differential scanning calorimetry (DSC). The partial substitution of iron for cobalt up to 10 at.% improves the stability of the alloys. The results obtained using various electrochemical techniques show that the new component does not improve notably the electrochemical characteristics of the basic composition alloy sample in KOH solutions. On the other hand, the high corrosion rate registered in HCl solutions does not allow us to obtain quantitative data.     

MoS2/Y分子筛微生物电解池阴极材料制备及其电化学性能

采用水热法合成了一系列不同比例的MoS₂/Y分子筛复合物,并将其制成碳基复合电解池阴极。线性扫描伏安法（LSV）测试表明,当MoS₂和Y分子筛质量比为5∶2、碳纸负载量为1.5mg/cm²时,阴极催化析氢性能最佳。通过SEM、TEM、XRD、XPS和BET对复合材料进行表征,SEM测试表明MoS₂/Y分子筛为片状和八面体相互交织叠加的云状形貌。BET测试表明其具有排列规整的微孔-介孔多级孔道结构,利于加速H⁺还原和H₂扩散。本文还考察了以MoS₂/Y分子筛作为微生物电解池（MEC）阴极的析氢性能。在MEC运行5个周期的产氢实验中,MoS₂/Y分子筛所产生的平均最大电流密度、氢气产率和产氢量等都高于Pt电极,且具有长期稳定性。因此,MoS₂/Y分子筛是一种适于实际应用的析氢催化剂。     

The influence of zeolite type A on metal concentrations in water and waste water

Investigations were made to determine the removals of calcium, copper, chromium, nickel, lead and zinc from water and waste water samples by different concentrations of zeolite type A and with zeolite type A forms where sodium had been partially exchanged for calcium. Metal concentrations were determined after a range of different treatments such as filtration, sedimentation in columns and centrifugation. The results indicated that the rate of removal of calcium hardness from samples was a function of the calcium hardness present in the samples. High concentrations of zeolite removed all the metals except chromium from water, but only lead, zinc and cadmium from synthetic waste water samples. In water samples containing cadmium, nickel, copper and zinc, an increase in the calcium exchanged for sodium in the zeolite resulted in a decrease in the percentage of nickel removed from suspension on mixing. At lower environmental concentrations, zeolite type A had no effect on the removal of metals from raw waste water samples.     

4A-沸石对CPVC性能的影响

考察了4A-沸石与有机锡稳定剂复合使用对CPVC流变性能、稳定性能、力学性能和维卡软化温度的影响.结果表明:4A-沸石与有机锡稳定剂具有协同作用,适宜的配比为1.5∶1,二者组成的复合稳定剂具有较高的性价比.     

The photoelectrochemical properties of anodic cadmium sulphide films

Anodic films of cadmium sulphide were grown in sodium sulphide solutions. The films are photosensitive and can be used as photoanodes in electrochemical solar cells. The performance of the cells is limited by the stoichiometry of the CdS films and by charge carrier recombination. The primary photocurrent quantum yield was measured at CdS film electrodes as a function of wavelength and electrode potential, and the results are discussed using a simple model. The implications of the experimental results for the design of electrochemical solar cells are examined briefly.     

Modification of surface properties of wool fabric with linde type a nano‐zeolite

Wool is a naturally occurring composite fiber consisting of keratin and keratin‐associated proteins as the key molecular components. The outermost surface of wool comprises a lipid layer that renders the surface hydrophobic, which hinders certain fabric processing steps and moisture management properties of wool fabrics. In this study, Linde Type A (LTA) nano‐zeolite (a Na⁺‐, Ca²⁺‐, and K⁺‐exchanged type A zeolite) was integrated onto the surface of wool using 3‐mercaptopropyl trimethoxy silane as a bridging agent. The resultant surface morphology, hydrophilicity, and mechanical performance of the treated wool fabrics were evaluated. Notably, the surface hydrophilicity of wool increased dramatically. When wool was treated with a dispersion of 1 wt % zeolite and 0.2 wt % silane, the water contact angle decreased from an average value of 148° to 50° over a period of approximately 5 min. Scanning electron microscopic imaging indicated good coverage of the wool surface with zeolite particles, and infrared spectroscopic evaluation demonstrated strong bonding of the zeolite to wool keratins. The zeolite application showed no adverse effects on the tensile and other mechanical properties of the fabric. This study indicates that zeolite‐based treatment is potentially an efficient approach to increasing the surface hydrophilicity and modifying other key surface properties such as softness of wool and wool fabrics. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42392.     

负载镉离子ZSM-5分子筛膜脱硫性能的研究

采用二次水热合成法制备出硅铝比为100的ZSM-5分子筛膜,用于脱除模拟汽油中的噻吩类硫化物。用X射线衍射仪和扫描电子显微镜对改性后的分子筛膜进行表征。考察了脱硫次数对脱硫效果的影响,测试了膜稳定脱硫时间,并进行再生实验。结果表明,经过Cd~(2+)改性的ZSM-5分子筛膜的骨架和形貌未发生改变,负载Cd~(2+)浓度为0.2 mol/L时,膜脱除噻吩类硫化物效果最佳,负载Cd~(2+)浓度为0.3 mol/L时,脱硫过程中分子筛膜出现堵塞情况。经0.2 mol/L Cd~(2+)改性过的ZSM-5分子筛膜两次脱硫后,噻吩的脱硫率可以达到81%,苯并噻吩的脱除率可以达到85%,稳定脱硫能持续32 h,再生后的膜脱硫效果良好。     

凝胶-燃烧法由轻烧菱镁矿制备纳米氧化镁

采用凝胶-燃烧法,以菱镁矿、乙酸铵及尿素为原料,加入成胶剂柠檬酸并烘干,在一定温度下点燃并退火即得纳米氧化镁。考察了前驱体溶液p H值、水及分散剂用量、退火等工艺参数对反应过程及最终产物性质的影响。通过X-射线衍射(XRD)、扫描电镜(SEM)及化学分析等对纳米氧化镁粉体进行表征后得到在优化条件下,纳米氧化镁的晶粒尺寸<100 nm,纯度为98.2%。     

Equilibrium and structural properties of gas molecules adsorbed in zeolite A

The equilibrium and structural properties of gas molecules confined within zeolite pore cavities were investigated via grand canonical ensemble Monte Carlo simulations. The Lennard-Jones 6–12 potential was chosen to be a representative model for the system of adsorbed argon gases inside 5A zeolites. The adsorption isotherm, the isosteric heat of adsorption, the energy distribution curve and the mass density profile were computed for the temperature of 203 K and 297 K over the bulk pressure range varying from 50 kPa to 400 kPa. The simulation results were compared with the experimental measurement, and, in the range of temperature and pressure considered here, the Monte Carlo data were shown to be in reasonable agreement with the available experimental values. It was observed that, at the higher surface coverage, adsorbate molecules formed the monolayer structure near the zeolite pore wall and promoted the second layer close to the cavity center under the influence of both argon-argon and argon-zeolite potential minima.     

LiFePO4的制备及其电化学性能

本文采用溶胶一凝胶法,以柠檬酸、EDTA和草酸为络合剂制备了LiFePO4,经XRD表征证明所得产品为橄榄石型磷酸铁锂。以放电曲线、循环寿命和电化学阻抗谱研究了LiFePO4的电化学性能,发现以柠檬酸为络合剂制备的LiFePO4的电化学性能最好。     

Encapsulation studies of hydrogen on cadmium exchanged zeolite rho at atmospheric pressure

Temperature programmed diffusion (TPDi) has been used to study the encapsulation of hydrogen in cadmium exchanged Cs-rho zeolite. The amount encapsulated after 2 h has been observed to be about 71 μmol/g at 50°C and 1 atm. This amount is over 30 times the amount of hydrogen encapsulated with NaX or NaA at 37°C for the same time and pressure. Upon increasing the encapsulation temperature to 100°C, the amount encapsulated increased to 161 μmol/g (2 h of encapsulation). At 200°C, the encapsulate is about 620 μmol/g, for the same pressure and time. With increasing temperature, more than one peak is seen in the TPDi spectra, revealing the availability of more than one site¹ for the encapsulation. 3 peaks are observed in TPDi spectra for the encapsulation at 200°C - at 107, 295 and 345°C. Large encapsulated amounts of hydrogen arise from blocking effects caused by the presence of cations (cadmium and/or cesium). Experiments for encapsulation of hydrogen on H-rho (hydrogen exchanged zeolite rho) show negligible uptake of hydrogen, proving that the presence of either the cadmium ion (5.05 Cd²⁺ per unit cell) or the cesium ion (1.87 Cs⁺ per unit cell) or both is directly responsible for the encapsulation of hydrogen.

For encapsulation at 200°C, possible migration of the encapsulate among the sites seems to occur with encapsulation time. This could explain the relative changes in the intensities of the 3 peaks in the TPDi spectra for the encapsulation at 200°C.     

沸石负载TiO2的光催化性能

以钛酸正丁酯和沸石为主要原料，采用溶胶-浸渍法制备出负载型纳米TiO₂/沸石催化剂。对亚甲基蓝模拟废水进行了光催化降解研究。分析比较了负载与非负载TiO₂降解效果的差异。探讨了pH对光催化降解率的影响。用FT-IR进行了结构表征。对催化剂进行了回收再生试验。结果表明，沸石负载的TiO₂光催化剂具有良好的光催化活性、不易失活及可再生性，TiO₂最佳负载量为2.98%。     

Mo incorporation in MCM-41 type zeolite

Mo-incorporated MCM-41 has been prepared by direct hydrothermal synthesis. XRD and N₂-adsorption measurements showed the characteristics of MCM-41. IR, FT-Raman and UV-VIS DR spectroscopic analyses gave the evidences for the incorporation of Mo in the framework of MCM-41. They are found to be stable and active for cyclohexanol and cyclohexane oxidation reactions with H₂O₂ as oxidant. Activity of this system has been compared with that of Ti-MCM-41 and molybdena impregnated on pure siliceous MCM-41. This revised version was published online in July 2006 with corrections to the Cover Date.     

沸石填料电化学反应器处理氨氮污水的研究

采用填充沸石的电化学反应器对20 mg/L的氨氮模拟污水进行处理研究,考察了影响氨氮去除效果的主要因素及处理效果。结果表明:当采用不锈钢板作为阴阳极、电流密度8 m A/cm2、电源电压60 V、初始p H=5、载铁斜发沸石填充量为200 g/L、曝气量为7 L/min、反应时间20 min时,废水中氨氮质量浓度能从20 mg/L降低到5 mg/L左右,达到国家城市污水处理厂一级A的排放标准(GB 18918—2002)。     

Structural properties and HDS activity of NiMo catalysts supported on lanthana modified zeolite type X and Y

In the search for the active catalysts of hydrodesulfurization reaction, an attempt was made to use zeolites as supports. A series of NaLaX, Mo/NaLaX and NiMo/NaLaX as well as NaLaY, Mo/NaLaY and NiMo/NaLaY catalysts was prepared and their performance in this reaction was studied. It was shown that crystalline structure of the lanthana forms of the above zeolites only little collapsed after ion-exchange and impregnation with active Mo and NiMo components. The NiMo catalysts supported on the zeolites studied were found active in thiophene hydrodesulfurization. The catalysts with lanthana after the first step of ion exchange were the most active.     

The electrochemical deposition of polyaniline at pure aluminium: electrochemical activity and corrosion protection properties

Polyaniline films were electrodeposited at pure aluminium from a tosylic acid solution containing aniline. These polymer films exhibited similar characteristics as pure polyaniline electrosynthesized at an inert platinum electrode, when removed from their respective substrates and dissolved in NMP. Both polymers had similar molecular weights and similar UV-visible absorption spectra. However, the aluminium substrate had a considerable effect on the electrochemical activity of the films. The polyaniline films deposited at aluminium appeared to lose electroactivity and the electrochemical impedance data were governed by the oxidized aluminium substrate. This is consistent with a galvanic interaction between the polymer and the aluminium substrate, giving rise to oxidation of the aluminium and reduction of the polymer. The polyaniline deposits appeared to offer only a slight increase in the corrosion resistance of aluminium. Surface potential measurements, using a scanning vibrating probe, showed that attack initiated underneath the polymer under anodic polarization conditions, indicating that chloride anions diffuse across the polymer to react at the underlying aluminium substrate.