高浓度硝酸溶液的扩散渗析过程研究

采用耐酸性良好的离子交换膜,研究含金属离子高浓度硝酸溶液的扩散渗析过程,用于回收水溶液中的硝酸.分别考察了进料液流量、硝酸浓度、酸水流量比等操作条件对非稳态扩散渗析过程的酸回收率和金属离子截留率的影响.结果 表明,硝酸的回收率随进料液流量的增大先提高后下降,随原料液中硝酸浓度的增大而下降,随酸水流量比的增大而增加.当进...     

扩散渗析-电沉积联合工艺资源回收酸性含铜树脂脱附液

分析了酸性含铜树脂脱附液的组成特征,成功开发了扩散渗析-电沉积联合工艺分步回收酸性含铜树脂脱附液中的酸和铜.研究结果表明,当扩散渗析装置料液流量为0.6L/h,自来水与酸性含铜树脂脱附液流量比为1.0时,回收酸中H+浓度约为1.12mol/L,酸回收率为80.2%(废液中H~+浓度为1.2mol/L,Cu~(2+)浓度为0.16mol/L),可返回树脂再生系统作为脱附剂回用;扩散渗析残液中铜离子平均浓度为0.12mol/L,调节pH至2.5后进入电沉积装置,当电沉积反应停留时间为300min,槽电压为9V时,电流效率平均为46.2%,铜回收率可达到98.2%,回收铜纯度为98.9%。开发的扩散渗析-电沉积联合工艺还可以推广应用于其他行业含重金属酸性废液的资源回收。     

扩散渗析法回收不锈钢酸洗废液中硝酸

采用扩散渗析法回收不锈钢表面酸洗废液中的硝酸.实验比较了两种扩散渗析膜用于酸回收的分离性能,考察了废酸流量、废酸浓度等对动态扩散渗析回收酸的浓度和金属离子的截留率的影响.实验结果表明:APS型阴离子交换膜的性能略优于DSV型膜,在合适的条件下,硝酸回收率大于85%,金属离子截留率大于95%.结果表明扩散渗析对于酸和金属盐的分离是一个极其有效的工艺.     

扩散渗析法回收铝箔腐蚀废液中硝酸

采用扩散渗析法回收铝箔腐蚀废液中的硝酸,主要考察流量、废液中硝酸铝浓度和硝酸浓度等因素对回收酸浓度、酸回收率以及铝离子截留率的影响.结果表明:回收酸浓度和酸回收率随着流量的增大而减小,随着废液中硝酸铝浓度的增大而增大;废液中硝酸浓度对回收酸浓度、酸回收率以及铝离子截留率的影响不大.综合本文的实验结果,酸回收率最高为84.90%,此时,流量为0.24L/h(流量比为1∶1)、废液中硝酸浓度为1.30mol/L、硝酸铝浓度为0.49mol/L.     

扩散渗析法回收精氨酸生产中的盐酸

为了解决精氨酸生产过程中的无机酸回收和循环再利用问题,采用阴膜扩散渗析法,针对模拟的精氨酸和盐酸混合液,在静态扩散条件下测定了盐酸的渗析系数,并考察动态扩散渗析操作参数如流速、流速比对酸回收率的影响.结果表明,采用DF-120阴离子交换膜,在静态扩散渗析中,盐酸能够顺利地透过膜,精氨酸几乎不能透过;动态扩散实验中流速、流速比对酸的回收率和回收酸的浓度有重要影响:随着流速的增加,盐酸的回收率逐渐降低,精氨酸的截留率基本上没有改变,均达到98.5％以上;流速为2 mL/min时,盐酸回收率最高,可达82％;水/料液流速比增大时,盐酸的回收率增大,但是过高的水/料液流速比又会使回收酸的浓度降低.经济核算表明,对于一个年产30 t精氨酸的装置,相对于中和法,膜扩散渗析法一年能节省的化学原料总费用约98万元,投资回收期为8个月.     

废退锡液中硝酸和锡的综合回收

通过考察铁盐、铜盐和亚锡盐对硝酸扩散系数的影响研究了采用扩散渗析法从废退锡液中回收硝酸的可行性,实际样品的研究表明,扩散渗析法回收硝酸的回收率在70％以上．余液利用离子膜-电沉积法回收其中的金属锡,最佳工艺条件为:温度30-40℃、槽电压3．5 V、电流密度1．0-2．3 A／dm2,并保持阳极液搅拌,此时锡的回收率达62％,电流效率在60％以上．结果表明,扩散渗析-离子膜-电沉积组合工艺可有效回收硝酸型废退锡液中的硝酸和锡,以实现其资源化利用．     

扩散渗析法回收硫酸稀土溶液中硫酸研究

对扩散渗析法回收硫酸稀土溶液中硫酸进行了实验研究，结果表明，料液中稀土浓度0～0．2mol／L范围内的较小变化对硫酸回收率没有明显影响；料液流量越大，即设备单位膜面积处理能力越大，硫酸回收率越低，回收液硫酸浓度及稀土截留率也越低，控制硫酸回收率在70％～80％较为合适；水料流量比越大，硫酸回收率越大，但回收液硫酸浓度及稀土截留率均降低，控制水料流量比在1左右较为合适；扩散渗析法能达到有效回收硫酸稀土溶液中硫酸的目的．     

集成膜法回收硫酸稀土溶液中硫酸

对减压膜蒸馏浓缩硫酸稀土溶液和与扩散渗析联合回收低浓度的硫酸做了研究．结果表明，水通量随着溶液中稀土及硫酸浓度的增大而减小，随温度升高、减压侧压力降低及料液流速增大而增大；先用减压膜蒸馏法浓缩硫酸稀土溶液，再用扩散渗析法回收硫酸对稀土截留率基本无影响，但大大增高了回收液硫酸的浓度，减少了扩散渗析的处理量，而浓缩倍数越大则效果越明显．     

含铜废水的膜电解

采用膜电解技术脱除含铜废水和含铜污泥废水的中Cu2+.对于含铜废水在以氨水、NaOH、草酸为阴极液电解质时,废水中Cu2+去除率分别为90.1％、50.4％和82％;废水中Cu2+浓度分别为11.75 mg/L、55.4 mg/L和20.92 mg/L.对于含铜污泥废水在以氨水、NaOH、硫化钠为阴极液电解质时,废水中Cu2+去除率分别为20.75％、61.06％和40.28％.膜电解过程能实现废水中Cu2+的去除和回收,但废水组成对膜电解过程的效果有着重要的影响.     

润滑油酮苯脱蜡溶剂回收用聚酰亚胺纳滤膜分离性能的研究

主要研究了聚酰亚胺纳滤膜分离酮苯一润滑油的性能．考察了操作压力、温度、料液流量、料液中润滑油浓度及酮苯比等因素对膜通量和截留率的影响，并考察了长期运行情况下膜的分离性能．结果表明，随压力增大、温度升高和料液流量增大，膜通量也随之增大；料液中润滑油浓度的增加使膜通量减小，料液中酮苯比的增加可增大膜的通量；以上各种情况对膜的截留率影响不大，截留率稳定在95％以上；在40天的运行期内膜的分离性能变化不大，说明此聚酰亚胺膜具有较强的抗污染能力．     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.