Solid-liquid solvent extraction of metal ions

An overview of extraction of some trace metal ions using molten solvent (lowmelting substance) during last two decades is presented. The development of this technique since itsinception is briefly traced. The comparison of extraction efficiency, thermodynamics and kineticsmainly involving extraction of rare earth ions between molten solvent extraction at high temperatureand usual liquid-liquid extraction at room temperature are discussed in detail. The variousparameters obtained from the previous and present studies such as equilibrium extraction constantK_(ex), pH_(1/2), thermodynamic and kinetic data are displayed in tabular form. Finally, the currentdemands, disadvantages and future prospects are also evaluated.

Transport of yttrium metal ions through fibers supported liquid membrane solvent extraction

A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liquid membrane was impregnated with different concentrations carrier.The experimental variables explored were concentration of yttrium(Ⅲ) ions,pH of source phase,PC-88A concentration in membrane phase,acid concentration in receiving phase and stirring speed.The pre-concentration of yttrium(Ⅲ) ions ...

Nickel solvent extraction from cold purification filter cakes of Angouran mine concentrate using LIX984N

Cold purification filter cakes generated in the hydrometallurgical processing of Angouran mine zinc concentrate commonly contain significant amounts of Zn, Cd, and Ni ions and thus are valuable resources for metal recovery. In this research, a nickel containing solution that was obtained from sulfuric acid leaching of the filter cake following cadmium and zinc removal was subjected to solvent extraction experiments using 10vol%LIX984N diluted in kerosene. Under optimum experimental conditions （pH 5.3, volume ratio of organic/aqueous （O：A） = 2：1, and contact time -5 min）, more than 97.1% of nickel was extracted. Nickel was stripped from the loaded organic by contacting with a 200 g/L sulfuric acid solution, from which 77.7% of nickel was recovered in a single contact at the optimum conditions （pH 1-1.5, O：A =5：1, and contact time =15 min）.

A Facile Procedure for Conjugate Addition of Amines to Electron Deficient Alkenes with Metal Oxide as Catalyst

A novel efficient procedure has been developed for the conjugate addition of amines to electron deficient alkenes. A series of metal oxides was synthesized for catalyzing the conjugate addition of amines and alkenes. After optimizing the reaction conditions, SrO was chosen as the most efficient catalyst for the reactions. The results show that the catalyst is very efficient for the conjugate addition of amines to electron deficient alkenes with the excellent yields in several minutes. Operational simplicity, without need of any solvent, low cost of the catalyst used, high yields, reusability, excellent chemoselectivity and applicability to large-scale reactions are the key features of this methodology.

The Effects of Oxidation States, Spin States and Solvents on Molecular Structure, Stability and Spectroscopic Properties of Fe-Catechol Complexes: A Theoretical Study

In this study, in order to explain the solvent and spin state effects on the molecular structure of catechol-Fe complex [Fe(cat)3]n﹣?where n = 2 and 3, Hartree Fock (HF)-Density Functional Theory (DFT) hybrid calculations are performed at the B3LYP/6-311g(d,p) level of theory. The binding energies of Fe2+ and Fe3+ in high-spin state are higher than intermediate and low-spin states which show that the complex formation in a high spin state is more favorable. The calculated binding energies at different solvents indicate that the binding energies in polar solvents are lower than non-polar solvents. Furthermore, spectroscopic studies including FTIR and Raman spectrum in various solvents reveal that the formation of intermolecular bonds between the oxygen atom of carbonyl group and the hydrogen atom of solvent causes a spectral red shift. The calculated FTIR and geometry parameters are in good agreement with previous experimental data. Donor-acceptor interaction energies are evaluated due to the importance of the charge transfer in the complex formation. It is observed that the free electrons of oxygen atom interact with the antibonding orbitals of the iron. Finally, some correlations between the quantum chemical reactivity indices of the complexes and solvent polarity are considered. The study indicates a linear correlation between chemical hardness and binding energies of [Fe(cat)3]3﹣?complex.

Microfluidic Behavior of Ternary Mixed Carrier Solvents Based on the Tube Radial Distribution in Triple-Branched Microchannels in a Microchip

Microfluidic behavior of ternary mixed carrier solvents of water-acetonitrile-ethyl acetate (2:3:1 volume ratio) was examined by use of a microchip incorporating microchannels in which one wide channel was separated into three narrow channels, i.e., triple-branched microchannels. When the ternary carrier solution containing the fluorescent dyes, hydrophobic perylene (blue) and relatively hydrophilic Eosin Y (green), was fed into the wide channel under laminar flow conditions, the carrier solvent molecules or fluorescence dyes were radially distributed in the channel, forming inner (organic solvent-rich major;blue) and outer (water-rich minor;green) phases in the wide channel. And then, in the narrow channels, perylene molecules mostly appeared to flow through the center narrow channel and Eosin Y, which is distributed in the outer phases in the wide channel, flowed through the both side narrow channels. A metal ion, Cu(II) as a model, dissolved in the ternary mixed carrier solution was also examined. The Cu(II) showed fluidic behavior, transferring from the homogeneous carrier solution to the water-rich solution in the side narrow channels through the triple-branched microchannels.

Synthesis,Structure and Characterization of Three Metal Molybdate Hydrates:Fe(H_2O)_2(MoO_4)_2·H_3O,NaCo_2(MoO_4)_2(H_3O_2) and Mn_2(MoO_4)_3·2H_3O

Three metal molybdate hydrates,Fe（H2O） 2（MoO4）2·H3O（FeMo）,NaCo 2（MoO4） 2（H3O2）（CoMo） and Mn 2（MoO4）3·2H3O（MnMo）,were synthesized by the mixed-solvent-thermal methods and characterized by singlecrystal X-ray diffraction.X-Ray photoelectron spectroscopy and bond-valence sums were applied to confirming the valance of Fe,Co,Mn and Mo.Thermo-gravimetric analysis and X-ray powder diffraction measurements indicate that the samples were converted to different structural compounds upon heating in air at 600 ℃ for 1 h.The magnetic properties of these compounds were studied.The dominant magnetic interactions are antiferromagnetic in nature.However,different synthesis conditions led to the diversity of magnetic properties of compound CoMo.

不同金属盐体系对锦纶66纤维结构与性能的影响

选用氯化钙、氯化锂、氯化铜及氯化锌四种金属盐,分别以去离子水和无水乙醇为溶剂配置成溶液,对锦纶66纤维进行络合改性处理,采用FTIR、DSC、XRD、SEM、单纤维拉伸研究不同金属盐及其溶剂种类对锦纶66纤维结构性能的影响。结果表明,经四种金属盐处理后,氯化铜对锦纶66纤维的结构性能影响最大、对纤维的络合作用最强,氯化锌对锦纶66纤维的结构、性能影响最小,氯化钙和氯化锂的影响程度居中,具体表现为红外光谱图中N-H振动峰向低波数移动,熔融温度下降、结晶度减小、拉伸断裂强度降低。选择氯化钙为金属盐络合剂时,以乙醇作为溶剂时对锦纶66纤维的结构、性能的影响作用大于以水为溶剂时,说明乙醇有利于金属离子与纤维之间形成络合作用。

Poly Ethylene Glycols as Efficient Media for the Synthesis of <i>β</i>-Nitro Styrenes from <i>α</i>, <i>β</i>-Unsaturated Carboxylic Acids and Metal Nitrates under Conventional and Non-Conventional Conditions

Poly ethylene glycols (PEG-200, 400, 600, 4000 and 6000) supported reactions were conducted with certain α, β-unsaturated acids in presence of metal nitrates under solvent free (solid state) and mineral acid free conditions. The reactants were ground in a mortar with a pestle for about 30 minutes. The aromatic acids underwent nitro decarboxylation and afforded β-nitro styrene derivatives in very good yield while α, β-unsaturated aliphatic carboxylic acids gave corresponding nitro derivatives. Addition of PEG accelerated rate of the reaction enormously. Reaction times substantially decreased from several hours to few minutes followed by highly significant increase in the product yield. Among the several PEGs PEG-300 has been found to be much more effective than other PEGs.

改性金属有机框架对甲基苯丙胺吸附及机理分析

将低共熔溶剂(DES)接枝到金属有机框架ZIF/磁性还原氧化石墨烯(MG)制备了一种复合吸附剂(DES@ZIF@MG),用于吸附水中甲基苯丙胺。采用SEM、FT-IR、BET、VSM、TGA等表征研究复合材料的微观形貌及理化性质。通过吸附动力学、吸附等温线以及吸附影响实验(pH、离子浓度和腐殖酸)探究吸附剂对甲基苯丙胺的吸附性能及机理。结果表明:吸附剂DES@ZIF@MG对甲基苯丙胺的吸附符合准二级动力学模型和Langmuir等温模型,说明吸附过程是以化学吸附为主导的能量均匀吸附。结合XPS表征进一步分析,DES@ZIF@MG对甲基苯丙胺的吸附过程中主要存在氢键作用、π-π作用、静电作用以及螯合作用。

金属离子对二甲亚砜依赖的RNA切割型脱氧核酶催化活性的影响

在高浓度有机溶剂中工作的RNA切割型脱氧核酶(RNA-cleaving DNAzyme,RCD)及其构筑的分子器件不仅拓展了DNA作为酶的能力,还可将功能核酸推进新的应用领域.本文研究了一个需要二甲亚砜才能工作的RCD(命名为E3)对金属离子的需求,发现二价金属离子对其催化活性至关重要,活性顺序为Zn^(2+),Mg^(2+)>Fe^(2+)>Pb^(2+)>Mn^(2+)>Co^(2+).以Mg^(2+)或Zn^(2+)为辅因子,表征了E3的速率-pH值关系及其与二者的结合比例.E3的催化速率-pH曲线在Mg^(2+)存在下为“钟形”,高速率的pH值范围为7.0~9.0;Zn^(2+)存在下为“尖峰”,速率最高时pH=7.0;E3与Mg^(2+)和Zn^(2+)的数量结合比例均为1∶1.另外,E3以Fe^(2+)为辅因子时易失活,Fe^(2+)被氧化成Fe^(3+)是失活的关键,加入还原剂可使其复活.进一步研究发现,Cu^(2+),Fe^(3+)和Ni^(2+)等金属离子可抑制Mg^(2+)或Zn^(2+)的作用,使E3的催化活性急剧降低.本文研究结果为理解E3的性质及催化机制提供了有用信息.

有机溶剂电解质在电化学冶金领域的应用

熔盐电解温度高、能耗大,水溶液电解易导致金属材料氢脆且不能用于活泼金属电解,采用室温非水电解质体系可以解决上述问题对比分析了离子液体、深共晶溶剂、有机溶剂等几种室温非水电解质的特点,重点介绍四氢呋喃-苯、碳酸乙烯酯、1,3-二甲基-2-咪唑啉酮等分别与AlCl_(3),ZnCl_(2),LiNO_(3)等构成的有机溶剂电解质体系在Al,Mg,Nd,La,Zn等金属电沉积方面的研究成果分析电解和电池用电解质的异同点,总结了苯类、醚类、醇类、脂类、四氢呋喃、咪唑啉酮、卤代烃等多种溶剂与有机金属盐、无机盐等溶质,金属氢化物、无机盐等添加剂组成的有机溶剂电解质的性质和特点,介绍其离子结构,概括其在电沉积过程中相关的化学和电化学反应,分析镀层性能与电沉积参数的关系和存在的问题,为从事非水电解质电化学冶金与材料制备研究提供思路。

石灰岩溶剂在金属矿方面的应用

石灰岩溶剂作为一种重要的工业原料,在金属矿的开采和冶炼过程中发挥着关键作用。本文首先介绍了石灰岩溶剂的性质与制备方法,然后详细阐述了其在金属矿开采和冶炼中的具体应用,最后对石灰岩溶剂在金属矿方面的应用前景进行了展望。

Zr-MOF固载聚离子液体对CO_(2)环加成反应的催化性能

通过无溶剂限域封装,将二溴对二甲苯和4,4′-联吡啶吸附至UiO-67材料微孔中,并原位聚合成聚离子液体PBpy-Br,得到兼具Br^(-),Zr-OH/Zr-OH_(2)和N杂环3种活性中心的复合材料PBpy-Br@UiO-67.采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)、^(13)C核磁共振波谱(^(13)C NMR)、比表面积分析(BET)和热重分析(TGA)等手段对材料进行了表征,并将其应用于催化CO_(2)与环氧氯丙烷的环加成反应中.在单因素实验基础上,通过响应面优化确定的最佳反应条件为反应温度100℃、p_(CO_(2))=0.1 MPa、催化剂用量(质量分数)0.22%以及反应时间22 h.在该条件下,环氧氯丙烷转化率达99.6%,催化剂循环使用5次后,转化率仅下降2.3%.此外,对PBpy-Br@UiO-67的普适性进行了研究,将其用于催化其它环氧化物与CO_(2)反应,转化率均在50%以上.研究结果表明,PBpy-Br@UiO-67催化剂具有反应条件温和及催化效率高的特点,为CO_(2)的固定与转化提供了新催化体系.

深共晶溶剂聚合物包覆膜传输分离铂、钯的研究

铂族金属(platinum group metal,PGM)元素中的铂(platinum)、钯(palladium)是一类具有高经济价值的稀有金属元素,广泛应用于工业、科学、医疗和高科技等领域。由于PGM的矿产供应量无法满足不断增长的市场需求。废旧汽车催化剂、电子废弃物等二次资源的回收成为缓解PGM供需矛盾的重要途径。本研究模拟实际废旧汽车催化剂浸出液,构建分离回收Pt(Ⅳ)、Pd(Ⅱ)的深共晶溶剂聚合物包覆膜电渗析集成体系。系统探究了体系中各工艺参数对模拟浸出液中铂族金属传输与分离的影响。结果表明,摩尔比为1∶1的TOPO/Thy对Pt、Pd传输性能最好,Pt、Pd的萃取效率均为99.90%,反萃取效率分别为65.96%、77.93%。而0.05 mol·L^(-1)KSCN作为反萃液对Pt、Pd有良好的分离效果,对Pt、Pd的反萃效率分别为62.54%、89.19%。本研究可为废旧催化剂的处理提供一种高效绿色环保的技术思路与理论依据。

环境化学品对重组发光大肠杆菌和502发光细菌的急性毒性研究

旨在评估构建的重组发光大肠杆菌相比于502发光细菌对多种化学品的毒性敏感性。以环境中常见的多种化学品为目标化合物,开展急性毒性测试实验,分别比较2种菌对3种无机金属、4种有机溶剂以及5种有机污染物的敏感度。实验结果表明,锌、铜、镉、丙酮、乙腈、乙醇、二甲基亚砜、3,5-二氯苯酚、甲醛、邻二甲苯、间二甲苯和对二甲苯对重组发光大肠杆菌的EC_(50)值(0.040、0.004、0.157、0.190、0.209、1.044、0.718、4.622×10^(-5)、6.62×10^(-4)、0.451、0.360和0.016 mol·L^(-1))均高于对502发光细菌的EC_(50)值(0.083、0.266、0.211、1.062、1.416、1.694、1.672、6.49×10^(-5)、1.014×10^(-2)、0.441、0.797和0.494 mol·L^(-1)),表明构建的重组发光大肠杆菌对受试化学品的毒性敏感性强于502发光细菌;且重组发光大肠杆菌的毒性测试结果与现有研究的生物毒性测定结果显示出更好的相关性。本研究表明重组发光大肠杆菌更适合作为生态监测的测试菌种,研究结果可为环境化学品的污染控制和生物毒性测试提供参考。

金属罐听外涂用水性丙烯酸改性聚酯的合成及研究

以三羟甲基丙烷,新戊二醇,二甘醇,苯酐,间苯二甲酸,己二酸,富马酸,偏苯三酸酐等为主要原料合成出了含微量双键的水溶性聚酯。然后进一步将该水溶性聚酯与苯乙烯,丙烯酸丁酯,丙烯酸-2-羟丙酯和丙烯酸等含亲水单元的丙烯酸酯类混合单体共聚反应,制得了一种丙烯酸改性水性聚酯树脂。对比研究了水性聚酯改性前后的性能差异,分别研究了水性聚酯做金属包装罐外涂白可丁涂层和水性丙烯酸改性聚酯做金属包装罐外涂光油涂层的物化性能。讨论了不饱和酸酐的用量、水性聚酯的羟值、接枝改性丙烯酸酯类单体用量以及接枝改性丙烯酸酯类单体的酸值和羟值对水性丙烯酸改性聚酯的影响。结果表明富马酸在聚酯中间体中占比2%左右时接枝改性效果最优;聚酯中间体的羟值和丙烯酸酯类单体的羟值在均在100 mg·g^(-1)~120 mg·g^(-1)范围(固体羟值)时,漆膜的硬度、柔韧性和耐化性达到最佳;水性丙烯酸改性聚酯的酸值在25 mg·g^(-1)~30 mg·g^(-1)(70%固含)时,水溶性和储存稳定性效果最好。当接枝改性丙烯酸酯类单体用量与聚酯用量质量比1∶3时,该水性丙烯酸改性聚酯制得的漆膜具有极佳的T弯性能和附着力以及物化性能,可用于制备水性罐听外涂白可丁涂层;当接枝改性丙烯酸酯类单体用量与聚酯用量质量比3∶1时,该水性丙烯酸改性聚酯制得的漆膜具有极佳的光泽、丰满度、柔韧性和优异的耐溶剂性能,且储存稳定性好,能广泛应用于制备罐听外涂光油涂层。

蛋黄卵磷脂的制备研究

研究了鸡蛋卵黄卵磷脂的制备工艺和产品质量分析。结果表明,使用95%乙醇分三次提取粗卵磷脂效果最佳,可制得卵磷脂含量约为70%的粗卵磷脂,得率约为10%;进一步使用ZnCl2沉淀制备卵磷脂效果最佳,使用10% ZnCl2纯化粗卵磷脂的回收率约为80%,产品中卵磷脂含量达94.25%;薄层层析结果表明,卵磷脂产品只有两个明显的斑点,分别为PC及PE两种成分。分光光度法测得卵磷脂的紫外最大吸收峰在215nm波长处。

离子液体在有机反应中的应用

室温离子液体 ,由含氮的有机阳离子和无机阴离子组成 ,可溶解各种有机、无机、金属有机化合物 .它们没有蒸气压、不易燃、容易循环使用 .近年已发现 ,离子液体可广泛地用于许多过渡金属化合物和酶催化的反应 .