阴极材料对MEC-AD体系产甲烷性能的影响评估

为了研究阴极材料对微生物电解池(MEC)耦合厌氧消化(AD)体系产甲烷性能的影响，分别将不锈钢、钛、泡沫铜、泡沫镍作为阴极，分析不同阴极材料所处体系在不同电压条件下的产气性能、阴极材料的电化学特性以及阳极微生物群落结构。结果表明：在4种阴极材料中，泡沫铜和泡沫镍所处的体系产甲烷、析氢性能最强，电子传递效率及电化学活性较不锈钢和钛强，所处体系中阳极产甲烷功能菌含量明显高于不锈钢和钛，故直接电子传递效率较强。由于泡沫铜易被氧化，故泡沫镍作为阴极材料具有一定的优越性。     

阴极材料及结构对电化学法水处理性能的影响

针对工业循环冷却水的结垢问题,实验研究了不同阴极(钛板、铜板和钛网)对电化学处理后水样的总溶解性固体和电导率的影响,得出阴极材料及结构对电化学法水处理性能的影响规律。结果表明,阴极为钛板时,最佳电解电压为25 V;阴极为铜板时,水中成垢离子的去除率与电解电压呈正比;阴极为钛网时,电解电压对电化学法水处理性能影响较小;钛板作阴极时的处理性能优于铜板;阴极为钛板时的处理性能优于钛网。     

电化学氧化处理难降解废水的研究进展

综述了国内外电化学氧化处理难降解废水的研究现状,详细阐述了电化学氧化机理,包括阳极氧化技术和阴极还原技术,介绍了影响电化学氧化降解效率的主要因素,包括电极材料、电化学反应器、溶液的pH值、溶剂体系以及其它因素.从有机污染物电化学氧化机理的研究、电极材料的研制、电板结构的研究和高效电解反应器的开发、对特定的电化学氧化系统...     

沸石填料电化学反应器处理低浓度氨氮的影响因素和机理

采用沸石填料电化学反应器处理低浓度氨氮废水,研究了阳极材料、粒子电极、阴极材料、电流密度、初始pH、曝气对氨氮去除效果的影响。结果表明,在钌铱锡阳极板(DSA)为阳极、活性碳纤维(ACF)为阴极、载铁斜发沸石为填料、电流密度为6 mA/cm2、pH为5、曝气量为5 L/min条件下,质量浓度为20 mg/L的模拟氨氮废水经处理后出水氨氮质量浓度为3 mg/L左右,且出水水质清澈。NH+4在直流电场作用下向阴极定向移动,曝气对阳极处理氨氮没有影响,·OH氧化氨氮可使氨氮质量浓度降低一半左右,氨氮降低至一定质量浓度时,·OH无法继续对其氧化,阴极附近氨氮质量浓度在20 min后基本保持不变。     

中温固体氧化物燃料电池阴极材料Bi1-xCaxFeO3-δ的制备及其性能

开发具有优异电化学活性的阴极材料对中温固体氧化物燃料电池(IT-SOFC)的应用至关重要.采用固相法制备无钴阴极材料Bi1-xCaxFeO3-δ(BCFx,x=0.1、0.2和0.3),通过该体系材料的物相结构、电导率、氧传输特性以及电化学性能研究表明,950℃时可以合成具有单相钙钛矿结构的Bi1-xCaxFeO3-δ...     

生物电化学系统中电活性生物膜催化污染物降解的研究进展

近年来,以电活性生物膜为基础构建而成的生物电化学系统成为环境领域的研究热点之一,其功能主要包括废水的处理和能源回收等。本文根据电活性生物膜在阳极与阴极功能的不同,介绍了阳极电活性生物膜以直接或间接方式为主的电子传递机制,其具备从多种污染物中回收电子的能力;阴极电活性生物膜具备高度的多样性和特异性,可以催化难降解污染物的还原降解。与此同时,本文也分析了电活性生物膜在现阶段研究的不足之处,包括较低的阳极产电功率密度以及阴极还未清晰的电子传递机制等问题。本文的分析表明,根据实际废水成分的不同,需要控制电活性生物膜群落的结构,实现不同功能微生物在电活性生物膜的协作,并通过对实际废水进行预处理,或者对电极材料进行优化来辅助电活性生物膜的催化过程,有助于达到高效去除废水中污染物的目的。     

DSA-泡沫镍电极电解法处理印染废水

采用泡沫镍材料作电解废水装置的阴极以提高单位电化学反应器体积的电流,使电极与废水界面之间的作用可在低电流密度下进行.用新型电极构成的电化学装置处理印染废水,研究过程的停留时间、施加的电流强度以及不同pH值对废水中的CODcr、汞和浊度去除效果的影响.结果表明电流强度增大,CODCr、汞和浊度的去除率均增加,最佳电流强度为1.0～1.2A;废水停留时间增加,各污染物的去除率增大,最佳停留时间约为20 min.     

在液体的连续流动中化合物的电化学沉积

本文介绍了一种清洗液体介质的设备,该设备是一种电化学室,包括具有贵重金属的阳极和至少一个由非金属支撑材料制成的阴极,其以隔离纤维的形式形成网孔或粘结起来的垫。该阴极支撑材料用金属处理。当电化学室工作时,被处理的化合物／或液体中的颗粒沉积在垫上起到阴极的作用。该阴极很容易被恢复原状,如当没有更多的化合物沉积在垫上时。该电化学室特别适用于处理包括工艺水、废水和地下水在内的水。     

沉淀法制备草酸镍及其电化学储能性能EI北大核心CSCD

开发具有优异电化学性能的阴极材料对混合超级电容器的应用至关重要。通过沉淀法成功合成了NiC_(2)O_(4)·2H_(2)O阴极材料,并对其微观结构、形貌及其电化学性能进行研究。结果表明:NiC_(2)O_(4)·2H_(2)O呈现出尺寸约0.5~2.0μm独特多面体颗粒结构,且每个颗粒由多晶所组成的,在1 A/g的电流密度下可实现1096.2 F/g的高比容量。组装后的草酸镍//活性炭混合超级电容器在3.7 k W/kg的高功率密度下,仍保持10.2 Wh/kg的能量密度。将两个混合器件串联可以点亮绿色和黄色发光二极管。NiC_(2)O_(4)·2H_(2)O作为一种新型、成本低廉、环境友好型阴极材料在电化学储能中具有潜在的应用前景。     

基于石墨纸阴极的电活化过硫酸盐高效降解阿特拉津

针对大多数阴极材料的析氢电势比过硫酸盐(persulfate,PS)的活化电势低,产氢反应抑制了PS的活化,利用析氢电势较高的石墨纸(graphite paper,GP)作为阴极,电活化PS降解废水中难降解有机污染物,为石墨材料作为阴极电活化PS提供理论依据.研究采用GP作为阴极,以阿特拉津(atrazine,ATZ)...     

Performance of floating cum tilted-wick type solar still with the effect of water flowing over the glass cover

A simple transient performance of floating cum tilted-wick type solar still has been presented by incorporating the effects of water flowing over a glass cover, heat capacity of tilted-wick water surface and floating-wick water surface. Explicit expressions for flowing water, glass, tilted-wick water surface and floating-wick water surface temperature and efficiency of the system have been derived. Numerical calculations have been carried out for a typical day in the month of March 2004. The relative standard deviations between the numerical and experimental results of different temperature components of the proposed still have been found. The results indicate that the relative standard deviations between theoretical and experimental results are less than 8% (glass cover), 2% (tiltedwick water surface), 1% (floating-wick water surface) and 2% (flowing water at the lower end of the glass cover) an average for the working hours of the day. Moreover, based on the numerical results, the following conclusions have been drawn: (i) glass cover temperature decreases significantly; (ii) the effect of water flowing over the glass cover has a fascinating effect on the production of distillate output during peak sunny hours; (iii) water flow rate of 1.5 m/s is optimum, and beyond it the efficiency decreases. Experimental investigations have been performed at Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore, India.     

大牛地气田回注井地层水与注入水配伍性实验研究

大牛地气田W-4污水回注井地层水总矿化度大约为16500mg/L,水型为CaCl2型。该井在回注过程中,回注压力急剧升高,影响正常回注。针对该问题进行了地层水与注入水配伍性研究分析。结果表明:该回注井地层水对外来碱性流体有较强的敏感性;当pH=8时,地层水中出现红色Fe(OH)3沉淀,随着pH升高,红色Fe(OH)3沉淀不断增加;地层水与注入水以不同比例均匀混合不产生结垢、沉淀,两者有良好的配伍性。根据分析结果,提出了相应的措施,对于解决回注压力升高问题具有指导意义。     

β-Cyclodextrin-ionic liquid polyurethanes for the removal of organic pollutants and heavy metals from water: synthesis and characterization

The removal of toxic contaminants from water remains a huge challenge for water supplying companies and municipalities. Both organic and inorganic (especially heavy metals) pollutants are often present in water distribution networks. There is at present no water treatment intervention that simultaneously removes both organic and inorganic pollutants from water to desirable levels. In our laboratories, recent studies have shown that both functionalized and unfunctionalized cyclodextrin (CD) polymers are capable of removing organic pollutants from water, with the functionalized CD polymers showing enhanced absorption capabilities. Ionic liquids (ILs) on the other hand have been reported to absorb heavy metals from aqueous media. In this paper, we report on the synthesis and characterization of several cyclodextrin-ionic liquid (CD-IL) polymers, a dual system that is capable of removing both organic and inorganic pollutants from water.     

含水量对硅胶柱层析同时分离纯化卵磷脂和脑磷脂的影响

研究了固定相初始含水量和流动相含水量对硅胶柱层析同时分离纯化卵磷脂和脑磷脂的影响。结果表明：含水量对硅胶柱层析同时分离纯化卵磷脂和脑磷脂有显著的影响。硅胶初始含水量在10％、12％(wt)和流动相含水量在0．5％0．9％(vol)范围内,卵磷脂(PC)和脑磷脂(PE)可实现基线分离,PC的回收率可达85％以上,PE的回收率可达70％以上。本研究结果对高纯度卵磷脂和脑磷脂的制备有一定的指导作用。     

聚合氯化铁混凝剂的电性及除浊性能研究

采取共聚与复合两种制备工艺 ,加入稳定剂 (S) ,合成了具有不同碱化度 (B)的稳定的高浓度聚合氯化铁混凝剂 (PFC)。通过测定zeta电位对其水解物的电动特性进行了研究 ;通过对模拟悬浊水样的絮凝实验 ,对其除浊性能进行了考察。结果表明 ,在pH >5的范围内 ,PFC比聚合氯化铝 (PAC)的zeta电位有所降低 ,PFC的zeta电位随pH的变化趋势与PAC也有所不同 ;PFC对模拟悬浊水样具有很好的除浊效果     

1—氯代片呐酮制备中冲料现象

在甲醇中氯化片呐酮以制备１－氯代片呐酮，有时会发生类似暴沸的冲料现象。究其原因，是甲醇中含有少量的水，水在氯化条件下，经次氯酸生成氯酸。氯酸不稳定，聚积至一定量时就可能发生分解反应而暴沸，通过实验找出了含水量的安全界限；观察了某些金属及其盐类对暴沸的影响；提出了预先处理含水甲醇，分解其中所含水的办法，以防止暴沸。     

改性沸石用于水的降氟实验研究

本文采用伊盟天然沸石作为吸附F^-的滤料，用于水的降F^-实验研究。实验结果表明：沸石的灼烧温度、沸石的粒度、是否改性对沸石降F^-效果有一定影响。而且经测定改性的20-40目无灼烧沸石降F^-效果最好。     

New experimental aspects of the carrier gas process (CGP)

The carrier gas process (CGP) based on humidification and dehumidification is a new interesting process (with respect to previous conventional processes such as multistage flash and reverse osmosis) for water desalination. The CGP contains several advantages such as flexibility in capacity, moderate installation and operating cost, possibility of using a wide range of thermal energies (geothermal, solar, recovered, direct fossil fuel, etc.) and simplicity (atmospheric pressure). The aim of this paper is to present the principal and characteristics of this technique based on experimental investigation. The present pilot plant unit consists of two packed columns, humidification and dehumidification, one heat exchanger and one air pre-heater. Most investigators have used solar thermal energy as the source for heating the saline water, but in this work electrical energy was used for heating the air stream. Besides this point most investigators have used a coil heat exchanger for condensation of fresh water but in the present work a packed column was used instead to do the same job. The experimental results of the work that was carried out at Bushehr Port, southern Iran, were: the effect of air pre-heater and coolant water temperatures, air, saline water, recirculating fresh water and coolant water flow rates on the amount of produced fresh water per unit of heat duty and fresh water production flow rate. It was found that the performance of the system strongly depended on the temperature and flow rate of the air pre-heater and the temperature and flow rate of the coolant water. However, it depended weakly on the flow rate of the saline water and fresh water re-circulation. It is expected that the unit would be of great potential for saline water desalination in arid areas and isolated islands.     

Hydrolysis Reactions at the Surface of Fluorozirconate Glass

The surface reaction products associated with the hydrolysis of ZBLA glasses have been characterized using X-ray photoelectron spectroscopy. The predominant surface reaction product in water and basic solutions is a zirconium (hydr)oxy-fluoride species. The compositional analyses indicate that the (hydr)oxyfluoride which forms in water has an average oxygen-to-fluorine ratio of ∼2/5. The Zr 3 d binding energy of this (hydr)oxyfluoride species was interpreted on the basis of its Pauling charge; this verified the compositional analyses and suggested a seven-coordinate surface species of the form ZrO₂F₅ or Zr(OH)₂F₅. It is proposed that zirconium (hydr)oxyfluoride is created in all aqueous solutions because of attack of Zr–F bonds by molecular water. The extent of reaction in water influences the surface concentration of the oxyfluoride species, but not their composition. In very acidic solutions, the surface concentration of (hydr)oxyfluoride is minimal, whereas in highly basic solutions the (hydr)oxy-fluoride species exhibits an increased oxygen-to-fluorine ratio.     

Performance of sea water dilution on the surface free energies of the crude oils in water-flooded carbonate rock

Although several investigations have studied the low-salinity water injection (LSWI) performance during the past decades, the effect of crude oil type on the interfacial tension (IFT) and wettability alteration is still in dark. In this regard, this study is aimed to obtain the thermodynamic energies including adhesion, cohesion and spreading coefficient during LSWI. To achieve this goal, IFT and static contact angle values of three different crude oils (i.e. light, medium and heavy) are measured as a function of sea water salinity. The obtained results revealed that the dilution of sea water can change the wettability of reservoir rock from oil wet state towards water wet state, while crude oil type implies no significant effect on the wettability alteration. Besides, the results illustrated that although the dilution of sea water unfavorably changed the IFT of light and heavy crude oils, it could favorably change the spreading coefficient.