PHYSICAL CHEMISTRY OF ADSORPTION OF COPPER,NICKEL AND COBALT ON LIGNITE FROM AMMONIACAL SOLUTIONS

The adsorption of Me(metal),NH_3 and CO_2 on lignite from ammoniacal solution containing metallicions such as Cu,Ni,and Co was investigated.Preliminary mechanism studied revealed that active carboxyland phenolic groups of humic acid in lignite as well as surface adsorption were involved.The rate of ap-proach to adsorption equilibrium on lignite was NH_3>Ni>Co>Cu andthe adsorption on lignite is Cu>Co>Ni>NH_3.The order of selective elution was NH_3>>Ni,Co>Cu.All metals were fully stripped and NH,could only be recovered partially.NH_3 adsorbed on lignite fron metal-ammoniacal solution is easily lost by volatilization,only a smallfraction remaining on lignite at a temperature of 120℃.CO_2 adsorbed physically in nature from ammonia-cal solution with a capacity of less then one percent was observed under the practical conditions generallyin hydrometallurgy.     

EFFECT OF SELECTED β-DIKETONES ON THE SYNERGICEXTRACTION OF COBALT(II) BY TRIPHENYL-PHOSPHINE OXIDE IN BENZENE

Abstract

Synergic extraction of Co(ll) by thenoyltrifluoroacetone (HTTA), Pivaroyltrilluoioacetone (HPvTA) or hexafiuoroacetylacetone (HHFA) mixed with triphenyiphosphine oxide (ph₃PO) in benzene from perchlorate media has been investigated. It ’ was found that in all the systems studied, Co(ll) is synergistically extracted as CoL₂.ph₃PO, where L stands for the different chelating ligands. The obtained equilibrum constants for the chelating and adduct systems indicated that: i- the weaker the acidity of the chelating ligand, the higher the overall aqueous phase formation constant of the metal chelate (β₂ ), ii- the sequence of the extraction constants (K_2,1 ) and the organic phase formation constants for the adduct ( β_2,1) as related to the chelating ligands is TTA> HFA > PvTA, iii- the stability of the adduct is related to both the structure and the pK_avalues of the chelating ligands.     

叔胺萃取分离钴(II)、铁(II)

研究了不必预先氧化二价铁,直接用叔胺从氯化物溶液中萃取分离钴(II)、铁(II)的新方法. 考察了不同改性剂对叔胺萃取钴(II)、铁(II)的影响以及各种因素对钴(II)、铁(II)萃取、洗涤及反萃的影响. 提出了用叔胺萃取分离钴(II)、铁(II)的最佳工艺参数.     

防霉涂料(II)

4.5.2 颜料分散、润湿剂[1,5]带有颜料的分散系统的分散机理是相当复杂的，但多数研究者在概念上具有如下的一致看法：分散过程首先是展色剂对颜料的浸润改良，即通过降低展色剂和颜料粉体界面的张力，增大浸润速度，借助于颜料的附聚或过度絮凝状态，除去主要存在于颜料表面的空气层。接着，经机械研磨，使颗粒达到原级粒子状态，最后，要防止这种已经分离的粒子重新相互结合，并保持稳定的分散状态。润湿分散剂的作用就是能吸附在上述的展色剂－颜料界面上，使之更迅速地形成更稳定的分散系统。水性防霉涂料用颜料分散剂一般是表面活性剂…     

Coordination of cobalt(III), nickel(II), copper(II), palladium(II) and platinum(II) with N-ethyl-N′-(4′-methylthiazol-2′-yl)thiourea (HL)

Coordination complexes of formula [ML₂], [CoL₃], [Pd(HL)Cl₂], [CuLCl(H₂O)] and [CuL₂(H₂O)₂] {L=anion of N-ethyl-N^′-(4^′-methylthiazol-2′-yl)thiourea; M=Pt^II, Pd^II or Ni^II} were prepared and characterized by elemental analyses, magnetic susceptibilities, and by IR, NMR, electronic and mass spectral measurements.     

电渗析与萃取耦合技术分离Ni(II)与Co(II)

为实现混合溶液中Ni(II)与Co(II)的分离,设计了电渗析与萃取耦合的集成分离技术,借助自行设计的设备,在选P507为萃取剂后,考察了电流密度、酸用量、体积流量、萃取剂皂化率、原料与萃取剂摩尔比、萃取方式等对分离效果的影响.结果表明:在实验范围内,电流密度3.8 mA/cm2,酸用量为理论用量的1.3倍,体积流量60 L/h、皂化率60%,原料与萃取剂摩尔比1:1.7为优取的操作条件;料液循环重复萃取,能显著提高分离效果.由此表明,电渗析与萃取耦合的分离技术,可分离混合体系中的Ni(II)、Co(II),且无需溶剂参与.     

Pd(II)-Cu(II)催化氧化净化PH3的动力学实验

传统的净化方法难以实现低成本、高效、选择性净化含磷化氢尾气,这限制了含磷化氢尾气的资源化技术的实现.文章利用自主筛选的催化剂,在实验室进行了Pd2 浓度、Cu2 浓度、反应温度、混和气氧体积分数、磷化氢质量浓度、混合气流速等因素对Pd(II)-Cu(II)水溶液净化含磷化氢气体影响的研究.实验结果表明,Pd(II)-Cu(II)催化剂在低温(22-73 ℃)、常压下(100 kPa)对质量浓度为850 mg/m3磷化氢气体净化效率可高达100%.并且催化剂稳定性随催化氧化反应温度的升高而降低,随被净化混和气中氧体积分数、吸收液中Pd2 浓度及Cu2 浓度增大而增强;催化氧化净化效率随混和气中磷化氢质量浓度升高而降低,随被净化的混和气流速降低而升高.     

Cyano-Bridged Heteropolynuclear Ni(II), Cu(II) and Cd(II) Complexes, [M(deten)2Ni(μ-CN)2(CN)2] n

Three new complexes [M(deten)₂Ni(μ-CN)₂(CN)₂] _n (M = Ni, Cu and Cd, deten = N,N-diethylethylenediamine) have been synthesized and characterized by chemical, thermal analysis, FT-IR and Raman spectroscopies. The crystal structure of the Cd complex has been determined by X-ray single crystal diffraction. Structural study reveals that the Ni²⁺ and Cd²⁺ ions are located on inversion centers, and adopt slightly distorted square-planar and octahedral geometries, respectively. In the crystal structure, the intermolecular N–H⋯N hydrogen bonds link the polymeric chains into a two dimensional network. Vibrational spectral data indicate the presence of two ν(C≡N) for complexes can be assigned to the terminal and bridging cyanides. The decomposition reaction take places in the temperature range 30–1000 °C in the static air atmosphere.     

First 3D heterotrimetallic Mn(II)–Cu(II)–K(I) polymer and three 3D Cu(II)/Mn(II) open network based on pyridine-2,3,5,6-tetracarboxylic acid

Four novel 3D coordination polymers, {[K₃Cu₂(H_0.5pdtc)₂ (H₂O)₆]·(H₂O)₂}_n (1), {[trans-K₂Mn₃(pdtc)₂ (H₂O)₁₁]·H₂O}_n (2), {[trans-K₂Mn₃(pdtc)₂ (H₂O)₁₀]·H₂O}_n (3) and {[cis-K₂Cu₂Mn(pdtc)₂ (H₂O)₁₀]·H₂O}_n (4), were synthesized by the self-assembly of potassium pyridine-2,3,5,6-tetracarboxylate (K₄pdtc) with metal salts. All of them contain infinite 1D stepwise chain. Notably, 2–4 have 2D network structures depending on the trans- and cis- hexacoordinated Mn(II) acting as connecters between the chains. Then, they further assemble into 3D or twin-plane structures by K(I) ions. 4 is the first Cu/Mn/K heterotrimetallic complex with H₄pdtc. The (H₂O)₆ clusters in 1 arranged stepwise along the complex chains owing to the host chains' template effect. The variable–temperature magnetic measurements reveal that weak antiferromagnetic interactions exist in complexes 1 and 4.     

Heteronuclear Cu(II)–Mn(II)–Cu(II) Complex Constructed from Metallo-Ligand Through Carboxylate Oxygens: Coexistence of Water Hexamers

A heteronuclear complex of [Mn(H₂O)₄(CuL)₂]₂·4H₂O 1 (H₂L = 2-hydrogen benzaldehydeneglycylglycine) has been synthesized and characterized by IR spectra, TGA, and single crystal X-ray diffraction analysis. The molecule consists of one $\text{Mn}{(\text{H}_{2}\text{O})_{4}}^{2+}$ Mn(H₂O) ₄ ²⁺ group and two symmetric groups [CuL]^? which are connected by carboxylate oxygen atoms. A discrete water hexamer composed of a planar tetrameric water ring and two pendent water molecules acts as a ‘glue’ to assemble adjacent [CuL]^? into a two-dimensional structure.     

Adsorption Behavior of Cadmium(II) and Lead(II) on Mesoporous Silicate MCM‐41

Abstract

This investigation examines metal ion adsorption on mesoporous silicate, MCM‐41, synthesized from sodium silicate solution and cethyltrimethylammonium bromide (CTAB). MCM‐41 has potential as an adsorbent material, with a regular hexagonal pore structure, large specific surface area, and large pore volume. The MCM‐41 synthesized for this investigation is characterized using powder X‐ray diffraction and nitrogen adsorption and desorption isotherms data. The adsorption behavior for cadmium(II) and lead(II) onto MCM‐41 was studied by contacting the mesoporous silicate with an aqueous solution of metal salts and acetylacetone. Both Cd²⁺ and Pb²⁺ were found to quantitatively adsorb onto MCM‐41. The results of this study suggest that MCM‐41 may have applications in the recovery of toxic metals from waste waters.     

Hydrothermal Synthesis of Cd(II), Mn(II) and Ni(II) Coordination Polymers Derived from Benzopenone-2,4′-carboxylate and N-door Ligands

Three new coordination polymers [Cd(L)(4,4′-bipy)_0.5]_n (1), {[Mn(L)(bpp)]·H₂O}_n (2) and [Ni(L)(2,2′-bipy)(H₂O)₂]_n(3) [H₂L = Benzopenone-2,4′-dicarboxylic acid, 4,4′-bipy = 4,4′-bipy ridine, bpp = 1,3-di(4-pyridyl) propane and 2,2′-bipy = 2,2′-bipyridine] have been synthesized and structurally characterized by elemental analysis, IR and X-ray diffraction. Single-crystal X-ray analyses revealed that the H₂L ligand acts as a bridge, exhibiting three coordination modes to link metal ion: bidentate chelating, bis-monodentate, monodentate. Compound 1 has 3-connected metal–organic framework with the (6³) topology notation; Compounds 2 and 3 are one-dimensional chain structures. The luminescent properties for compound 1 was investigated.     

Ruthenium(II) acetylacetonato–sulfoxide complexes

The water-soluble Ru^II acetylacetonato–sulfoxide complexes, cis-Ru(acac)₂(DMSO)₂ (1) and Ru(acac)₂(meso-BESE) (2), were synthesized (BESE=1,2-bis(ethylsulfinyl)ethane=EtS(O)(CH₂)₂S(O)Et). Both complexes were characterized by ¹H and ¹³C{¹H} NMR, UV–Vis, and IR spectroscopies, as well as MS, elemental analysis, solution conductivity, and cyclic voltammetry, while the molecular structure of 2 was determined also by X-ray crystallography. All sulfoxide ligands are S-bonded. The complexes were tested against human breast cancer cells (MDA-MB-435S) using an in vitro MTT assay, a colorimetric determination of cell viability; IC₅₀ values of >2000 and 1500 ± 100 μM were determined for 1 and 2, respectively, while cisplatin exhibits an IC₅₀ value of 30 ± 5 μM.     

Removal of Zinc(II) and Manganese(II) from Crude Phosphoric Media by Bis(2,4,4‐Trimethylpentyl) Phosphinic Acid (Cyanex‐272)

Purification of commercial phosphoric acid produced by the wet process from toxic heavy metals such as zinc and manganese is considered to be a very important environmental and economical process. The commercial bis(2,4,4‐trimethylpentyl)‐ phosphinic acid (Cyanex‐272) is proposed as an extractant for the efficient removal of Zn(II) and Mn(II) from crude phosphoric acid samples of concentrations of 25% and 45%. Various parameters affecting the extraction rate of Zn(II) and Mn(II) were investigated. The results were assessed to obtain the optimum conditions for the fast and efficient removal of both cations from crude phosphoric acid using Cyanex‐272 as an extractant in various diluents. The selectivity sequence of different diluents for Zn(II) and Mn(II) extraction were: kerosene > n‐hexane > cyclohexane > toluene > benzene > chloroform. The stripping of the investigated metal ions is efficiently performed with ammonium thiocyanate which has been selected as a suitable stripping agent.     

木犀草素Zn(II)和Cu(II)配合物的合成及电化学性质研究

在无水乙醇溶液中,用木犀草素和醋酸铜、醋酸锌合成两种鲜见报道的木犀草素金属配合物,并通过元素分析、红外光谱、电子光谱和摩尔电导等表征手段,确定了配合物的结构。并研究了木犀草素Zn(II)和木犀草素Cu(II)配合物化学修饰碳糊电极在pH 5 B-R缓冲溶液中的电化学行为。     

含磺酸钠聚合物微凝胶的制备及对Cu(II)和Pb(II)的吸附

采用回流-沉淀聚合制备了含磺酸钠聚合物微凝胶(SSPMg),通过扫描电子显微镜(SEM)、比表面及孔隙度分析(BET)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)等对其结构性能和化学组成进行了表征,并考察了SSPMg对Cu(II)和Pb(II)的吸附性能。结果表明,对苯乙烯磺酸钠占共聚单体总质量17.5%的微凝胶(SSPMg-4)在pH值=5时吸附效果最佳;吸附过程更符合准二级动力学和Langmuir等温吸附模型,以单分子层的化学吸附为主,包括络合、离子交换和静电吸附作用;吸附过程ΔG小于0、ΔH大于0,表现为常温下的自发吸热过程。298.15 K时,SSPMg-4对Cu(II)和Pb(II)的Langmuir理论最大吸附量分别达523.56 mg/g和568.18 mg/g。经过6次循环使用后,SSPMg-4对Cu(II)和Pb(II)的去除率保持在初始去除率的92%以上。     

Mass Transfer and Immobilized Organic Phase Instability Studies for Cobalt(II)–Nickel(II) Separation by PEHFSD

Pseudo-emulsion-based hollow-fiber strip dispersion (PEHFSD) technique was examined as an alternative to solvent extraction for simultaneous separation and concentration of cobalt(II)–nickel(II) mixture using Cyanex-272 as the extractant. Experiments were carried out by continuous recirculation of the feed and pseudo-emulsion phases through a hollow-fiber module. The separation factor increased rapidly after 60 min of operation. The maximum value after 120 min of operation was ～128 (pH = 6.5) for the operating conditions studied. The mass transfer resistance from the extraction reaction appeared to be dominant. The results of mathematical modeling of the mass transfer process indicated that higher separation factor and extraction rate can be achieved using PEHFSD in comparison to solvent extraction. Mixing of the stripping and the feed solution was observed at high dispersed phase volume fraction in the pseudo-emulsion and low flow rate of this phase. The maximum value of backtransport flux from the stripping phase due to mixing was estimated to be approximately two orders lower than the initial extraction rates.     

选择性絮凝的方法及其机理(II)

对选择性絮凝的现有方法按照其特点进行了系统的分类,从吸附角度和动力角度两个大方面考虑选择性絮凝的方法。吸附角度又包括增减颗粒上的活性质点数、絮凝剂分子量、絮凝剂用量、分子识别和絮凝剂形态五个方面。文中的分类方式基本涵盖了所有的选择性絮凝方法,并对选择性絮凝方法的机理和分类规律进行了阐述。这里着重介绍除增减颗粒活性质点数外的其他方法,同时,根据选择性絮凝分类方法的规律,首次提出了几种新方法并进行了探索性论述,如用合适的剪切力提高絮凝的选择性等。     

水杨醛缩4-氨基安替比林与Zn(II),Ni(II),Co(II)配合物的合成和表征

以水杨醛、4-氨基安替比林和醋酸盐为原料,在酸性条件下,以乙醇为溶剂,合成了水杨醛缩4-氨基安替比林希夫碱及其配合物。考察了反应时间、温度、原料配比对该合成的影响。结果表明,反应的最佳条件为:水杨醛∶4-氨基安替比林∶醋酸盐(摩尔比)=1∶1∶1,在80℃条件下反应5 h,产率可达80%。通过红外和紫外光谱进行表征,研究了他们的性质。