Template Effect on Structure and Morphology of Ni(OH)2 Powders Prepared by Hydro-chemical Method

Ｐｒｏｐｅｒｔｉｅｓｏｆｐｏｗｄｅｒｓａｒｅｃｌｏｓｅｌｙｒｅｌａｔｅｄｔｏｔｈｅｉｒｓｔｒｕｃｔｕｒｅｓａｎｄｍｏｒｐｈｏｌｏｇｉｅｓ ,ｍａｉｎｌｙｉｎｃｌｕｄｉｎｇｐａｒｔｉｃｌｅｓｉｚｅ,ｓｈａｐｅａｎｄｃｒｙｓｔａｌｌｉｎｉｔｙｏｆｐｏｗｄｅｒｓ[1].Ｆｏｒｐｏｗｄｅｒｓｐｒｅｐａｒｅｄｂｙｈｙｄｒｏ ｃｈｅｍｉｃａｌｍｅｔｈｏｄ ,ｓｔｒｕｃｔｕｒａｌａｎｄｍｏｒ ｐｈｏｌｏｇｉｃａｌｃｏｎｔｒｏｌｏｆｐｏｗｄｅｒｓｗｅｒｅｃｏｎｖｅｎｔｉｏｎａｌｌｙｒｅａｌｉｚｅｄｂｙｔｈｅａｄｊｕｓｔｍ…     

液膜法处理废镉镍电池浸出液的研究

研究了乳状液膜从废镉镍电池的浸出液中有选择性地分离镉的问题，确定了以二异丙基水杨酸(DIPSA)和三辛烷基硫化磷(TBPS)为液膜载体和协同载体的乳状液膜体系．实验考察了载体用量、浸出液的pH值、内水相中硫酸的浓度、油内体积比(Roi)以及乳水比(Rew)对该乳状液膜迁移Cd^2 、Ni^2 和Co^2 的影响，以及油相回用和资源利用．结果表明，在最佳液膜操作体系下，Cd^2 的回收率在98％以上，Ni^2 和Co^2 的损失率(即迁移人内水相)均在1％以下，油相可回用．     

从废旧镍-镉电池中回收镍和镉

提出采用湿法冶金回收工艺回收废旧镍－镉电池中的镍和镉。该工艺首先用硫酸将废旧电池溶解，调节pH除铁，获得含有镍和镉的溶液。然后采用旋转圆盘电极体系回收金属镉。高速旋转的电极既可以随时清除枝型晶体，又抑制了浓差极化。金属镉的回收率达到98.0%以上；镍的回收采用化学沉淀法，回收率可以达到99.5%。     

均匀沉淀法制备纳米MgO

以硝酸镁和尿素为原料,聚乙二醇为分散剂,用均匀沉淀法合成了氢氧化镁,并将其煅烧制得纳米MgO.讨论了反应温度、反应时间、反应物配比对氢氧化镁产率的影响.确定了合成氢氧化镁工艺;用视比容分析方法确定了制备纳米MgO煅烧工艺;并通过SEM对纳米MgO的形貌进行了分析,得到了平均粒径为50 nm分散较好的纳米MgO.实验合成氢氧化镁的最佳条件为:反应温度125℃;反应时间5h;反应物配比(尿素/Mg(NO3)2.6H2O)为6:1;最佳煅烧工艺为:温度500℃,时间2h.     

30℃时K_2SO_4和（NH_4）_2SO_4在CH_3OH－H_2O溶液中的共饱和度研究

本研究测定了３０℃时Ｋ２ＳＯ４－（ＮＨ４）２ＳＯ４－ＣＨ３ＯＨ－Ｈ２Ｏ四元体系的共饱和度，分析了ＣＨ３ＯＨ含量对Ｋ２ＳＯ４及（ＮＨ４）２ＳＯ４共饱和度的影响，得出了以ＣＨ３ＯＨ为盐析剂，从Ｋ２ＳＯ４和（ＮＨ４）２ＳＯ４的水溶液中晶析Ｋ２ＳＯ４的规律，为Ｋ２ＳＯ４和（ＮＨ４）２ＳＯ４的分离提供理论依据。     

氢氧化二乙二胺合镉(Ⅱ)溶液对纤维素纤维的溶解性能

选择氢氧化二乙二胺合镉(Ⅱ)为溶剂,测试了7种不同种类纤维在该溶液中的溶解度,为溶解法鉴别纤维素纤维提供基础数据. 改变溶液的浓度及温度,测试纤维素纤维的溶解度变化情况;用可见分光光度计测溶解前后溶液的透射率,根据透射率的变化,推断纤维及溶液中化学键的变化. 研究结果表明:溶液浓度越大,对纤维的溶解能力越强. 随着温度的升高,纤维在溶液中的溶解度逐渐增大;当达到一定温度后,溶解度又逐渐降低;当温度升高到一定值时,溶液分解,失去了对纤维的溶解能力.纤维的溶解机理为:纤维素纤维分子间氢键断裂,且有新的化学键生成.     

Structural characteristics of spherical Ni(OH)_2 and its charge/discharge process mechanism

1　INTRODUCTIONSince Ni MH batteries came to the market in1990, the improvement of the performances oncathode active materials of nickel hydroxides havebeen mainly based on empirical optimization[1 6].Nowadays, more sophisticated methods are appliedto correlate the chemical composition processes microstructure electrochemical performance of thematerials. In the last two decades, a lot of investi gations have been done concerning electrochemicalmechanisms for Ni MH bat…     

ICP-MS/HG-AFS测定不锈钢容器中熬煮酸菜重金属含量变化

研究用不锈钢容器酸菜熬煮砷、汞、铅、镉、铬、镍、铜等元素的含量变化.以微波消解预处理样品,用ICP—MS、AFS测定熬煮后汤汁、酸菜样品中各元素含量.用不锈钢容器熬煮酸菜,可使锅体中铅、铬、镍、铜溶出较多,镉少量溶出,基本无砷、汞溶出.其中:汤料中铅、铬、镍、铜、镉含量分别增加了92.90%、4.66倍、57.53%和58.28%、25.00%;酸菜中铅、铬、镍、铜、镉含量分别增加了73.71%、1.54倍、71.23%和27.68%、20.78%.     

Structural characteristics of spherical Ni（OH）2 and its charge／discharge process mechanism

Spherical Ni(OH)2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni(OH)2 was investigated by scanning electron microscopy and transmission electron microscopy and compared with that of traditional Ni(OH)2. The results show that the spherical nickel hydroxide consists of Ni(OH)2 spheres with a reticulate structure of platelet-like, which is almost arranged radially and the crystalline grains intervene and connect with each other to form a three-dimensional net. The spherical Ni(OH)2 particle is full of pores,crannies between cleave planes. It is supposed that this structure is beneficial to the structural stability for the spherical particles during the charge/discharge processes and can improve the cycle life of the electrode; the pores and the crannies in spherical particles can shorten the proton diffusion distance and speed its velocity, which may result in that the local polarization is lowered. The electrochemical performances of the spherical Ni(OH)2 are improved by enhancing the conducting properties of the crystalline lattice due to its quick proton diffusion.     

电池正极新材料氢氧化高镍[Ni(OH)_3]的研制

采用水溶液氧化沉淀法,试制了Ni(OH)3粉末材料.实验选用Na2O2等多种氧化剂与无水NiCO3,NiSO4·6H2O等四种镍盐发生反应,比较了制取高纯氢氧化高镍的反应效果及结果,并从中确立了较合理的氧化剂和镍盐配方.在此基础上,分析了反应液温度和反应液pH值两个主要参数对氢氧化高镍生成的影响,确立了制取氢氧化高镍的基本方法.     

Performance of a combined capacitor based on ultrafine nickel oxide／carbon nanotubes composite electrodes

A new sol-gel process for the preparation of ultrafine nickel hydroxide electrode materials was developed. The composite electrodes consisting of carbon nanotubes and Ni(OH)2 were developed by mixing the hydroxide and carbon nanotubes together in different mass ratios. In order to enhance energy density, a combined type pseudocapacitor/electric double layer capacitor was considered and its electrochemical properties were characterized by cyclic voltammetry and dc charge/discharge test. The combined capacitor shows excellent capacitor behavior with an operating voltage up to 1.6 V in KOH aqueous electrolyte. Stable charge/discharge behaviors were observed with much higher specific capacitance values of 24 F/g compared with that of EDLC (12 F/g) by introducing 60% Ni(OH)2 in the anode material. By using the modified anode of a Ni(OH)E/Carbon nanotubes composite electrode, the specific capacitance of the cell was less sensitive to discharge current density compared with that of the capacitor employing pure nickel hydroxide as anode. The combined capacitor in this study exhibits high energy density and stable power characteristics.     

Electrogenerative leaching of nickel sulfide concentrate with ferric chloride

In order to utilize the chemical energy in hydrometallurgical process of sulfide minerals reasonably and to simplify the purifying process, the electrogenerative process was applied and a dual cell system was introduced to investigate FeCl3 leaching of nickel sulfide concentrate. Some factors influencing the electrogenerative leaching, such as electrode structure, temperature and solution concentration were studied. The results show that a certain quantity of electrical energy accompanied with the leached products can be acquired in the electrogenerative leaching process.The output current and power increase with the addition of acetylene black to the electrode. Varying the components of electrode just affects the polarization degree of anode. Increasing FeCl3 concentration results in a sharp increase in the output of the leaching cell when c(FeCl3) is less than 0.1mol/L. The optimum value of NaCl concentration for electrogenerative leaching nickel sulfide concentrate with FeCl3 is 3.0 mol/L. Temperature influences electrogeneratire leaching by affecting anodic and cathodic polarization simultaneously. The apparent activation energy is determined to be 34.63 kJ/mol in the range of 298 K to 322 K. The leaching rate of Ni^2 is 29.3% after FeCl3 electrogenerative leaching of nickel sulfide concentrate for 620 min with a filter bag electrode.     

废镍催化剂回收镍并生产高纯硫酸镍的研究

研究了从废镍催化剂中生产硫酸镍,废镍催化剂通过碱洗酸溶,除去杂质钡和硅之后,通过调节溶液的pH值进行精制和浓缩,以除去铁锌等杂质,在液固比(mL/g)为5、硫酸质量浓度为40%,浸泡时间为100 min,浸泡温度是95℃时镍的浸出率最高,可达到97.5%.最终得到的晶体通过X射线衍射和热重分析表明,其结构为N iSO4.6H2O,化学分析表明镍含量为22.6%.     

氧化锌与真空烧结氧化镍复合粉体的光催化降解研究

采用溶胶凝胶法分别制备了Ni(OH)2和Zn(OH)2前驱体,Ni(OH)2凝胶分别在管式炉和真空烧结炉中制备NiO粉体,Zn(OH)2凝胶在管式炉中烧结制备ZnO粉体。通过X射线衍射仪进行表征,研究了甲基橙在目标催化剂水悬浮液中的光催化降解性能。结果表明:在0.5Pa的氧分压下烧结所得的氧化镍比纯氧化镍光催化性能有所提高,说明适当地引入氧空位,有利于催化剂的电子空穴的分离。氧化锌与0.5Pa的氧分压烧结的氧化镍以质量比为2:1复合时,光催化性能最佳,达到了93.099%,说明氧空位和p-n结的存在综合提高了光催化性能。     

低品位氧化锌矿在NH_3-NH_4HCO_3-H_2O体系中的浸出动力学研究（英文）

对高钙低品位氧化锌矿在NH3-NH4HCO3-H2O体系中的浸出动力学进行了系统研究.研究结果表明,氧化锌矿浸出过程遵循＂未反应核缩减＂模型,即遵循动力学方程：1-（1-α）1/3=k.t.反应的表观活化能Ea=6.489 kJ/mol,浸出过程由外扩散过程控制.增强搅拌强度、提高总氨浓度及反应温度均可加快该矿石中锌的浸出速率,并在一定范围内提高锌的浸出速率.     

酸溶粉煤灰制备混凝剂及其处理污水效果

为了提高粉煤灰的利用价值,采用酸溶法提取其中的铝、铁元素,制备粉煤灰基混凝剂.以硫酸为酸浸液,固定酸灰比为3:1,考查不同酸溶方式的溶出效果,并利用制得的混凝剂处理生活污水.实验结果表明:硫酸浓度或反应温度的提高有助于粉煤灰中铝、铁的溶出.添加NH4F为助溶剂,铝、铁的总溶出率可达63.42%,但存在F-的二次污染.经过高温焙烧后粉煤灰中铝、铁酸溶性降低,但添加碳酸钠且配比达到0.06以上时,熟料中铝酸溶性提高;由此制得的混凝剂处理污水时,适宜投量为1.2 mL/L,效果优于市售混凝剂,COD、TP的去除率分别为69%、95%,剩余SS低于20 mg/L.     

重金属污泥制砖固化及其浸出试验

将含重金属污泥与粘土按不同的比例混合制砖固化,并通过毒性浸出试验研究了不同砖块的浸出液中As、Zn、Pb、Cd含量随浸出时间的变化。结果表明,重金属的浸出浓度在浸出初期逐渐升高,然后As的浸出浓度趋于稳定,而Zn和Cd的浸出浓度则呈下降趋势;As、Zn、Cd的浸出浓度与污泥的添加量有关,随着污泥添加量的增大,As的浸出浓度增大,Zn和Cd的浸出浓度是先增大,然后趋于稳定,但污泥添加量对Pb的浸出浓度影响不大;在制砖粘土中添加1%的Fe2O3和12%的含重金属污泥时,As、Zn、Cd和Pb的浸出浓度低于规范要求,固化效果良好、安全可靠。     

纳米羟基磷灰石的镉离子吸附性能

以硝酸钙、磷酸、氨水为原料,采用共沉淀法合成了纳米羟基磷灰石粉体.以硝酸镉水溶液作为模拟废水,用Visual MINTEQ软件对模拟废水的溶液化学特征进行了计算,主要研究了溶液的初始pH值、反应时间以及镉离子(Cd2+)初始浓度等因素对纳米羟基磷灰石的镉离子吸附量的影响.实验结果表明,纳米羟基磷灰石的镉离子吸附性能在溶液初始pH为4～9的范围内比较稳定,其去除水溶液中镉离子的过程符合准二级动力学模型,并且与朗缪尔等温吸附和弗伦德里希等温吸附均表现出了较高的相关性,反映了纳米羟基磷灰石吸附水溶液中镉离子的反应以离子交换作用为主的特点.纳米羟基磷灰石不仅镉离子吸附容量大,而且初期吸附速率很快,是一种性能良好的环境矿物吸附材料.     

New technique of comprehensive utilization of spent Al2O3 -based catalyst

A new technology was developed to recover multiple valuable elements from the spent Al2O3-based catalyst by X-ray phase analysis and exploratory experiments. The experimental results show that in the condition of roasting temperature of 750 ℃ and roasting time of 30 min, molar ratio of Na2O to Al2O3 of 1.2, the leaching rates of alumina, vanadium and molybdenum in the spent catalyst are 97.2%, 95.8% and 98.9%, respectively. Vanadium and molybdenum in sodium aluminate solution can be recovered by precipitators A and B, and the precipitation rates of vanadium and molybdenum are 94. 8% and 92. 6%. Al（OH）3 was prepared from sodium aluminate solution in the carbonation decomposition process, and the purity of Al2O3 is 99. 9% after calcination, the recovery of alumina reaches 90. 6% in the whole process; the Ni-Co concentrate was leached by sulfuric acid, a nickel recovery of 98. 2% and cobalt recovery over 98.5% can be obtained under the experimental condition of 30% H2SO4, 80 ℃, reaction time 4 h, mass ratio of liquid to solid 8, stirring rate 800 r/min.     

纳米Ni/SiO2核壳结构粒子的制备和表征

采用微波多元醇法制备了纳米Ni粒子,再通过水解正硅酸乙酯(TEOS)得到SiO2,实现对纳米Ni粒子的表面包覆,形成Ni/SiO2核壳结构。通过X射线衍射和透射电镜对包覆前后的粒子进行了观察分析。结果表明,微波多元醇法制备的Ni纳米粒子平均粒径100 nm,分散较均匀;包覆后的Ni粒子表面有一层非晶态的SiO2壳层,壳层的厚度随TEOS的浓度增大而增加。