Adsorption of copper ions on porous ceramsite prepared by diatomite and tungsten residue

In order to realize resource utilization of industrial tungsten residue and treatment of heavy metal wastewater in mining and metallurgical area of south China, a novel ceramsite was prepared with the main raw materials of diatomite and tungsten residue. The adsorption behavior of copper ions in solution on the ceramsite was investigated. Results indicated that the surface of the newly-developed ceramsite was rough and porous. There were lots of pores across the ceramsite from inner to outside. MnFe₂O₄ was one of the main components of the ceramsite. The Cu²⁺ adsorption capacity by the ceramsite reached 9.421 mg/g with copper removal efficiency of 94.21% at 303 K, initial Cu²⁺ concentration of 100 mg/L and dosage of 0.5 g after 300 min adsorption. With increase of ceramsite dosage, the total adsorption amount of Cu²⁺ increased, but the adsorption capacity decreased. The adsorption capacity increased with the increase of solution pH. The isothermal adsorption of Cu²⁺ by the ceramsite fitted the Freundlich model better. The adsorption mainly occurred on a heterogeneous surface, and was a favorable process. The adsorption process closely followed the pseudo-second kinetic equation. In initial stage of wastewater treatment, the adsorption process should be controlled mainly by diffusion, and the removal of Cu²⁺ can be improved by enhancing agitation.     

Adsorption of nickel(II) cations by natural zeolites

The composition of a natural specimen of zeolite-containing rock of a Transbaikal field including Ca[Al₂Si₇O₁₈] · 6H₂O calcium heulandite and KAlSi₃O₈ potash fieldspar impurity is confirmed with X-ray phase analysis and infrared spectroscopy. The time necessary for attaining adsorption equilibrium in a zeolite-aqueous nickel sulfate solution system is estimated. The limiting adsorption at different temperatures is found from the Langmuir equation. Thermodynamic and kinetic characteristics of the adsorption of nickel (II) cation on natural minerals are calculated.     

Properties of nanocrystalline copper prepared by vacuum-warm-compaction method

Nanocrystalline Cu with average grain size of 22.8-25.3 nm was prepared by vacuum-warm-compaction method. Scanning electronic microscope, HMV-2 type microhardness tester, X-ray diffractometer, and 6157 type electrometer were used to determine the microstructure, microhardness and electrical resistivity of as-prepared nanocrystalline Cu, respectively. The results show that the microhardness of nanocrystalline Cu increases with larger pressure, longer duration of pressure or higher temperature. The highest microhardness of nanocrystalline Cu is 3.8 GPa, which is 7 times higher than that of coarse-grained copper. The electrical resistivity of as-prepared specimens is (1.2-1.4)×10-7 Ω·m at temperature 233-293 K, which is 5-6 times higher than that of the coarse-grained copper.     

超临界流体干燥法(SCFD)制备纳米级铜粉

采用均相溶液化学还原法与超临界流体干燥法相结合的组合技术,制备了高纯度、高分散性、高抗氧化性的立方晶系纳米级铜粉.通过考察反应体系pH值、反应物配比、无水硫酸铜浓度、反应温度、分散剂对反应速度及产物粒径的影响,得出最佳工艺条件是:pH值为2,无水硫酸铜与次亚磷酸钠的摩尔比为1:1.3,无水硫酸铜浓度为0.2 mol/L,采用复合非离子型分散剂,反应温度为50℃,反应时间为2 h.经超临界流体干燥制得的纳米铜粉用IR、TEM、XRD进行了表征.结果表明,粉体颗粒为球形,粒径约为25 nm;与普通干燥法比较,超临界流体干燥法实现了粉体干燥与表面改性一步完成.最后,讨论了纳米铜粉对润滑油摩擦学性能的影响.     

Ceramic-lined compound copper pipe prepared by SHS process

Self-propagating high-temperature synthesis(SHS) is a new kind of material synthesis technique, and has characteristics with respect to low energy consumption, short synthetizing time, high production quantity, high product purity and no environmental pollution. When SHS combines with centrifugal casting, ceramic-lined compound copper pipe(CLCCP) can be produced, the inner surface of copper pipe can produce ceramic coatings having good wear and corrosion resistance. In order to increase the densification degree, combining strength and toughness of ceramic layer, the effects of additives such as SiO2, CrO3, Na2B4O7 and ZrO2 are researched, adding SiO2 and CrO3 in thermite, the densification degree of ceramic layer increases, adding Na2 B4 O7 in thermite can increase combining strength, adding ZrO2 in thermite can increase the toughness of ceramic layer. CLCCP is used in tubular billet crystallizer, having excellent service effects and decreasing the production cost of tubular billet.     

连续等径角挤压制备超细晶铜

介绍一种制备超细晶材料的新技术———连续等径角挤压,它将连续挤压技术应用于制备超细晶材料的等径角挤压工艺,解决了传统等径角挤压不能制备大尺寸超细晶材料的问题,该技术对超细晶材料的推广应用具有重要意义。通过DEFORM3D对铜的连续等径角挤压过程的数值模拟,得到变形过程中金属的流动、应变场和温度场情况,并对不同变形速度和摩擦条件下的变形过程进行比较,得到优化的工艺参数,并以此参数进行实验。实验结果表明,连续等径角挤压后铜的硬度明显上升,连续等径角挤压3道次后,硬度趋于饱和;连续等径角挤压12道次后,铜的平均晶粒尺寸为400 nm。     

超声场辅助矿浆电解法制备超细铜粉

采用铜精矿为原料，通过机械活化和超声场的辅助作用，直接在矿浆电解槽中将铜精矿制备成平均粒度小于10 μm的超细铜粉。分析矿浆电解制备超细铜粉的基本原理，研究电流密度和超声波对超细铜粉粒度和形貌的影响。结果表明：提高电流密度有利于超细铜粉的形成，随着电流密度的增加，铜粉粒度不断下降，比表面积不断上升；与未经超声处理相比，采用超声场辅助矿浆电解法制备得到的铜粉粒度趋于下降，比表面积上升，且随着超声时间的延长，粒度下降越多，比表面积增加越大。     

Sorption of copper (II) cations from aqueous media by a cellulose-containing sorbent

The process of distribution of copper ions in the “aqueous CuSO₄ solution/cellulose-containing sorbent” system is studied. The sorption isotherms for Cu²⁺ ions obtained within the temperature range of 296–363 K indicate the exothermic behavior of the process. The experimental data on sorption of Cu²⁺ ions are treated within the Langmuir model and the theory of volume filling of micropores. Both models allow us to describe well the process of sorption. The value of maximum sorption of copper ions determined from the Langmuir model is in better agreement with the experimental data. During sorption of Cu²⁺ ions, the cellulose sorbent was found to behave as a weak-acid cation exchanger, in which the sorption sites are represented by -COOH groups in the H⁺ or salt forms.     

纳米金属铜靶材的微结构与性能

采用自悬浮定向流方法制备金属Cu纳米粉体,在25℃和1.0~1.75 GPa的高压下,单向模压成型,制备含量高于95%的高密度纳米金属Cu晶体材料。用透射电镜、X射线衍射谱和场发射扫描电子显微镜对样品的结构进行表征。结果表明:X射线衍射分析的平均晶粒尺寸未退火时为19.9 nm,退火后为30.5 nm(TEM观察约为60 nm),颗粒基本为球形;样品中除了纳米晶粒外,还出现孪晶结构;孪晶是纳米Cu粉在超高压作用下形变的重要特征之一;纳米晶体Cu样品的电阻率在室温下约为1.56×10-7Ω.m,是粗晶Cu在室温下电阻率(0.167×10-7Ω.m)的9.3倍。     

Recrystallized microstructural evolution of UFG copper prepared by asymmetrical accumulative rolling-bonding process

Copper sheet with grain size of 30-60μm was processed by plastic deformation of asymmetrical accumulative rolling-bonding(AARB)with the strain of 3.2.The effects of annealing temperature and time on microstructural evolution were studied by means of electron backscattered diffraction(EBSD).EBSD grain mapping,recrystallization pole figure and grain boundary misorientation angle distribution graph were constructed,and the characteristics were assessed by microstructure,grain size,grain boundary misorientation and texture.The results show that ultra fine grains(UFG)are obtained after annealing at 250℃ for 30?40 min.When the annealing is controlled at 250℃for 40 min,the recrystallization is finished,a large number of small grains appear and most grain boundaries consist of low-angle boundaries.The character of texture is rolling texture after the recrystallization treatment,but the strength of the texture is faint.While second recrystallization happens,{110}1ī2+{112}11ī texture component disappears and turns into{122}212cube twin texture component.     

半固态挤压铸造ZCuSn10铜合金的组织演变

对ZCu Sn10铜合金坯料进行液态浇注和半固态挤压成形,通过组织演变的分析,研究不同工艺对ZCu Sn10铜合金半固态挤压液固协同流动性的影响。结果表明,不同工艺对ZCu Sn10铜合金挤压组织液固协同流动性影响不同,在930℃保温40 min挤压速率为12 mm/s可获得固液协同流动较好的挤压成形件组织。相同挤压工艺条件,半固态挤压成形件各个位置组织差异较大。近冲头位置保持初始半固态组织;试样中部位置为固液两相共存的半固态组织、固相颗粒圆整度较高;试样最前端的微观组织中以液相为主,固液两相分布均匀性较差。     

大变形异步叠轧法制备超细晶铜材的再结晶研究

采用大变形异步叠轧法制备了超细晶铜材,研究了再结晶过程中铜材的组织演变过程、织构变化过程以及晶界特征分布情况.结果表明:经过220℃×35min和220℃×60min退火处理,分别获得0.1-0.2μm和0.5～1.0μm范围的超细晶铜材,主要晶界类型均属于低能晶界;六道次叠轧后的无氧纯铜板材在退火初始阶段仍为轧制织构,但由于剪切力的作用织构强点位置发生偏移、强度有所降低;随着退火时间的延长,织构组分发生变化,C取向发生孪晶转变,流向B/G取向.     

异步叠轧法制备超细晶铜的组织及性能

室温下对纯铜进行异步叠轧,制备超细晶铜材,研究了异步叠轧过程中纯铜显微组织演变、界面复合以及力学性能的变化。结果表明:搓轧区的存在促进了界面的复合和晶粒的细化;经六道次异步叠轧后可以使纯铜的平均晶粒尺寸从30μm减小到1μm,抗拉强度为450.3 MPa,屈服强度为346.5 MPa,轧制面显微硬度为108.5 HV,横截面显微硬度为66.3 HV,纵截面显微硬度为77.4 HV,伸长率为3%。     

Adsorption of copper using macroporous phosphonic acid resin

1　INTRODUCTIONTheresearchpapersaboutsynthesischaracteriza tionandadsorption propertyofpolymericmaterialshavebeenpublishedinrecentyears[15] .Macroporousphosphonicacidresin (PAR)isanovelpolymericma terialwhichcontainsafunctionalgroupof[-PO(OH) 2 ].Ithasquitealotofadvantagessuchashighadsorptioncapacity ,easyregenerationandconvenientoperation .SoPARcanbeusedwellintheadsorptionofmetalions .Butsofar ,therehasn tbeenareportonadsorptionforCu(Ⅱ )whichisoneofimportantelementsinhydrometallurg…     

铜模铸造块体Fe-Ga合金的磁致伸缩性能和结构特征(英文)

采用惰性气体保护下的感应熔炼铜模吹铸方法,制备具有非平衡快速凝固组织、晶粒沿温度梯度取向生长的Fe100-xGax(x=16～20)合金棒。XRD分析判定棒材主要为无序A2相结构且具有110轴向择优取向。随着Ga元素含量的增加,合金的饱和磁化强度明显降低,低场动态响应迅速增加。快速凝固获得的 Fe82Ga18合金棒的纵向饱和磁致伸缩在30kA/m磁场强度下为92×10-6。吹铸法制备的Fe100-xGax(x=16～20)合金棒材大的磁致伸缩性能源自快速凝固过程中所保留下来的高温无序A2相和合金内部所具有的大量沿100方向排列的短程有序富Ga原子团簇,这些富Ga团簇最终诱发畸变 DO3相的生成,正如(200)衍射峰发生劈裂所示。有序化转变生成的DO3相对该合金的磁致伸缩性能不利。     

铝热反应法制备Mo增强铜基纳米复合材料的组织与性能

采用铝热反应-自蔓延烧结法制备了钼质量分数分别为5%、10%、20%的Mo增强铜基复合材料。采用X射线衍射仪、光学显微镜、扫描电镜和透射电镜分析了复合材料的物相及微观组织形貌,并研究了钼添加量对复合材料力学性能、导电性能、热膨胀系数的影响。结果表明:该工艺制得的复合材料基体晶粒尺寸均达到纳米级,致密度均达到90%以上,硬度较纯铜提高40%以上,导电性能良好(72%IACS以上)。随着钼质量分数的增加,复合材料的硬度增加,致密度、电导率及热膨胀系数下降。当钼质量分数为20%时,复合材料的致密度为91.88%,电导率为72%IACS,硬度是纯铜的2倍,热膨胀系数较纯铜降低了13%,综合性能最佳。复合材料硬化的主要机理为强化相钼和铜基体弹性模量差别引起的模量硬化。     

点焊电极表面电火花沉积TiB_2涂层的特征

在CuCrZr电极表面通过电火花振动沉积制备了TiB_2功能涂层,测试了功能涂层的显微形貌、物相、硬度以及界面元素分布.试验表明,TiB_2涂层电极具有典型的电火花涂层结构,存在明显的元素互扩散,表明功能层与基体之间为冶金结合.但TiB_2涂层结构不致密,存在裂纹和孔洞,硬度较低.随着电火花电容和电压的增加.涂层的硬度降低.元素扩散和涂层氧化的加剧,是导致涂层硬度降低的主要原因.由于基体Cu的气化、脆性剥落和熔敷棒的切削作用,沉积TiB_2后基体质量反而降低.高电压下电火花沉积以及预涂敷Ni,都会导致基体质量降低更多.     

硫脲对喷射电铸纳米晶铜组织与性能的影响

采用喷射电铸法制备了不同硫脲浓度下的纳米晶铜铸层,用SEM、XRD方法分析了硫脲对纳米晶铜铸层微观结构和晶粒大小的影响,并对纳米晶铜铸层的力学性能进行了测试.结果表明,硫脲能细化晶粒,致密铸层组织,显著提高铸层的抗拉强度和显微硬度;电铸液中硫脲浓度为10 mg/L时,可获得晶粒尺寸为29 nm的致密铜铸层,其显微硬度和抗拉强度分别为3.1 GPa和645 MPa.电铸液中硫脲浓度从5 mg/L增至10 mg/L时,纳米晶铜铸层的择优取向由(220)晶面转变为(111)晶面.     

Nanosized copper powders prepared by gel-casting method and their application in lubricating oil

Nanosized copper powders were prepared by a gel-casting method using copper nitrate, acrylamide (AM) and N, N′-methylenebisacrylamide (MBAM) as the main raw materials. The as-prepared copper powders were characterized by X-ray diffractometry and scanning electron microscopy, and then added into a 48# industrial white oil. Dispersion and wear properties of the compounded lubricating oil were tested. The results show that the copper powders prepared are of high purity, fine dispersibility with mean particle size of about 60 nm and with a narrow particle size distribution. The nanosized copper powders can be well dispersed in the lubricating oil. The addition of the copper powders obviously improves the anti-wear properties of the lubricating oil owing to their good self-repairing performance. Compared with 48# industrial white lubricating oil, the friction coefficient of GCr15 steel with the compounded oil containing 0.6% copper powders reduces by 0.07 and nearly no wear chippings are found in the scratches of the friction counter parts.