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1.
LIX 973N diluted with Iberfluid was used to co‐extract copper and nickel from ammoniacal/ammonium carbonate aqueous media. The influence of equilibration time, temperature, equilibrium pH and extractant concentration on the extraction of both metals has been studied. It was observed that neither copper nor nickel extraction is sensitive to temperature and equilibrium pH, however nickel extraction equilibrium is reached at a longer contact time (20 min) than that of copper (5 min), in addition nickel extraction depends greatly on the extractant concentration in the organic phase. For a solution containing 3 g dm−3 each of copper and nickel and 60 g dm−3 ammonium carbonate, conditions were established for the co‐extraction of both metals, ammonia scrubbing and selective stripping (with H2SO4) of nickel and copper. Using the appropriate extractant concentration the yield (extraction stage) for both metals is near 100%, whereas the percentage of nickel and copper stripping is also almost quantitative. © 1999 Society of Chemical Industry  相似文献   

2.
《分离科学与技术》2012,47(15):3149-3165
Abstract

Biosorption of nickel (II) and copper (II) ions from aqueous solution by dead sphaeroplea algae in natural and acid treated forms were studied as a function of concentration, pH, and adsorbent dose. The optimum pH for nickel (II) and copper (II) biosorption was found to be 6.0 and 4.0 respectively. The metal ion uptake increased with initial metal ion concentration studied up to 500 mg/L. Both the Freundlich and Langmuir adsorption models could fit the equilibrium data. The adsorption reasonably fitted the Lagergren kinetic model. Further the biomass was characterized by FTIR spectra. Surface area values are measured to be 0.9 and 2.1 m2/g for natural and acid treated forms respectively. The maximum adsorption capacity was found to be 3.40, 4.15 mmol/g for nickel (II) and 2.21, 3.41 mmol/g for copper (II) in natural and acid treated forms respectively.  相似文献   

3.
Extraction and separation of copper, zinc, nickel, and cadmium from calcium and magnesium in concentrated smelting wastewater by synergistic solvent extraction using a mixture of 2-hydroxy-5-nonylacetophenone oxime (Mextral 84H) and bis(2,4,4 -trimethylpentyl)-phosphinic acid (Cyanex 272) in an aliphatic diluent (DT-100) was studied. The effects of extractant concentrations, equilibrium pH, organic-to-aqueous phase ratios, system temperature, and extraction and stripping efficiencies on the extraction performance of the heavy metals were investigated. Extraction of pH isotherms showed that addition of Cyanex 272 to Mextral 84H causes obvious synergistic shifts for zinc and cadmium and a slightly antagonistic shift for nickel. The separation factor of cadmium over magnesium was 155.7 and the ΔpH50 values between the metals were over 1.00 pH units. Semi-continuous tests for the metals extraction, scrubbing, and stripping were conducted in a continuous extraction apparatus with conditions further optimized for separation of the metals. Nearly 100% of the copper and nickel and over 98% of the zinc and cadmium were recovered with less than 0.1 mg/L copper and nickel, 26 mg/L of zinc, and 10 mg/L of cadmium remaining in the raffinate. A process in which all valuable metals are extracted simultaneously and stripped selectively at optimal conditions is proposed that is entirely feasible for the separation of copper, zinc, nickel, and cadmium from calcium and magnesium in concentrated smelting wastewater. The study determines the fundamental parameters for the treatment of smelting wastewater by solvent extraction.  相似文献   

4.
《分离科学与技术》2012,47(7-8):587-597
Abstract

This paper reports the results obtained on copper, zinc, and nickel uptake by activated sludge in a completely mixed unit. Removal of these heavy metals from wastewater occurs by uptake and by precipitation, the latter being particularly important in the cases of copper and zinc. The amount of heavy metal taken up by the microorganisms at equilibrium varies with influent concentration for the three metals studied. The values obtained range from 2.3 mg/g VSS for copper at 1 mg/L in the influent to 57.4 mg/g VSS for nickel at influent 25 mg/L. Soluble metal removal from wastewater increases in percentage with influent concentration, being higher for copper and lower for nickel. Experiments with mixtures of these metals have also been carried out.  相似文献   

5.
《分离科学与技术》2012,47(9):2067-2080
Abstract

In this paper, a process is reported for the recovery of cobalt and nickel from copper raffinate solutions using partially saponified Cyanex 272 and D2EHPA as the extractants. The aqueous feed contains 1.65 g/L cobalt and 16.42 g/L nickel. More than 99.9% cobalt separation was achieved with 0.13 M Cyanex 272 (60% neutralized with alkali) in two counter‐current stages at an aqueous to organic phase ratio of 1.1:1. Co‐extraction of nickel was 0.18% only. Stripping of cobalt from a loaded organic phase was carried out with synthetic spent electrolyte solution at an organic to aqueous phase ratio of 2.5 in two counter‐current stages to generate a pregnant electrolyte solution to produce cobalt metal by electrowinning. Similarly, optimum conditions for nickel extraction with 60% neutralized 1 M D2EHPA at O/A ratio of 1.4 in 2 two stages and stripping of metal with synthetic spent electrolyte at O/A ratio of 1.6 in two stages were standardized. Extraction and stripping efficiencies were >99% and the flowsheet of the process is demonstrated.  相似文献   

6.
《分离科学与技术》2012,47(6):1365-1381
Abstract

A composite chitosan biosorbent (CCB) was prepared by coating chitosan on to ceramic alumina. The adsorption characteristics of the sorbent for copper and nickel ions were studied under batch equilibrium and dynamic flow conditions at pH 4.0. The equilibrium adsorption data were correlated with Langmuir, Freundlich, and Redlich‐Peterson models. The ultimate monolayer capacities, obtained from Langmuir isotherm, were 86.2 and 78.1 mg/g of chitosan for Cu(II) and Ni(II), respectively. In addition, dynamic column adsorption studies were conducted to obtain breakthrough curves. After the column was saturated with metal ions, it was regenerated with 0.1 M sodium hydroxide. The regenerated column was used for a second adsorption cycle.  相似文献   

7.
ABSTRACT

Equilibrium and kinetic studies have been carried out on the extraction of nickel from sulfate solutions using bis(2,2,4 trimethylpentyl) phosphinic acid HDTMPP, “Cyanex 272tm”- It was found that nickel extraction in HDTMPP was favored by the presence of sodium in the organic phase and that equilibrium nickel concentration could be written in terms of the pre-equilibrated extractant concentration

Kinetic studies were carried out using the rising drop method, reaction orders were determined with respect to the aqueous phase nickel concentration, Ni2+, the aqueous phase sodium concentration, Na + the pH, the organic phase dimer concentration ------ and the organic phase sodium salt concentration ---- In addition, it was found that the extraction kinetics could be explained in terms of an aqueous phase interfacial reaction accompanied by diffusion through the interface. Mass transfer coefficient values were determined indicating extraction rates for metal extraction into HDTMPP were the same order of magnitude as those found for HDEHP.  相似文献   

8.
DP‐8R and ACORGA M5640 extractants diluted in Exxsol D100 were used to co‐extract cobalt and nickel from aqueous acidic sulfate media. The influences of equilibration time, temperature, equilibrium pH and reagent concentrations on the extraction of both metals have been studied. It was observed that both cobalt and nickel extraction are slightly sensitive to temperature but are pH dependent. Metal extraction equilibria are reached within about 5 min contact time. In addition, cobalt extraction depends on the extractant concentration in the organic phase. For a solution containing 0.5 g dm?3 each of cobalt and nickel and an initial pH of 4.1, conditions were established for the co‐extraction of both metals and selective stripping (with H2SO4) of cobalt and nickel. Using the appropriate reagent concentrations the yield (extraction stage) for both metals exceeded 90%, and stripping of cobalt and nickel was almost quantitative. Copyright © 2004 Society of Chemical Industry  相似文献   

9.
根据HG/T 4696—2014《工业碱式碳酸镍》的质量要求,研究开发出一条制备工艺简便且易实现产业化的高密度碱式碳酸镍生产工艺。研究了一种加压喷雾的方式进料、使得物料在反应系统内更加均匀、易形成大颗粒、从而提高碱式碳酸镍产品松装密度的制备工艺。通过探究反应温度、反应pH、硫酸镍浓度、碳酸钠浓度、反应转速对松装密度的影响,寻找出影响较大的工艺条件开展正交实验,得出最佳工艺条件:40 ℃条件下,采用镍离子质量浓度为100 g/L的硫酸镍溶液加压喷雾法进料,用106 g/L碳酸钠溶液在自动控制系统下控制反应pH为8.0左右,反应过程中反应转速控制在300 r/min,即可制备出松装密度为0.7 g/cm3以上、杂质含量低且形状为类球形的碱式碳酸镍产品。  相似文献   

10.
Various chelating ligands have been investigated for the cloud point extraction of several metal ions. However, limited studies on the use of the Schiff base ligands have been reported. In this work, cloud point extraction behavior of copper(II) with N,N′‐bis(salicylaldehyde)Ethylenediimine Schiff base chelating ligand, (H2SALEN), was investigated in aqueous concentrated sulphate medium. The extraction process used is based on the formation of hydrophobic H2SALEN–copper(II) complexes that are solubilized in the micellar phase of a non‐ionic surfactant, i.e. ethoxylated (9.5EO) tert‐butylphenol. The copper(II) complexes are then extracted into the surfactant‐rich phase above cloud point temperature. Different parameters affecting the extraction process of Cu(II), such as equilibrium pH, extractant concentration, and non‐ionic surfactant concentration were explored. The extraction of Cu(II) was studied in the pH range of 2–11. The results obtained showed that it was profoundly influenced by the pH of the aqueous medium. The concentration factor, Cf, of about 17 with extraction efficiency of E % ≈100 was achieved. The stoichiometry of the extracted complex of copper(II) was ascertained by the Yoe–Jones method to give a composition of 1:1 (Cu:H2L). The optimum conditions of the extraction‐removal have been established as the following: (1) 1.86 × 10?3 mol/L ligand; (2) 3 wt% surfactant; (3) pH of 8 (4) 0.5 mol/L Na2SO4 and (5) temperature of 60 °C.  相似文献   

11.
《分离科学与技术》2012,47(13):3065-3077
Abstract

In this work, a new cloud point extraction (CPE) method was developed for the separation and preconcentration of copper and nickel. The analyte was complexed with 3‐[(8‐{[(E)‐2‐hydroxyimino‐1‐methylpropylidene] amino}‐1‐naphthyl) imino]‐2‐butanone oxime (H2mdo) in the initial aqueous solution and octylphenoxy polyethoxy ethanol (Triton X‐114) was added as a surfactant. After phase separation, based on the cloud point in the mixture, and dilution of the surfactant‐rich phase with methanol containing 0.1 mol l?1 HNO3, the enriched analytes were determined by flame atomic absorption spectrometry. After optimization of the complexation and extraction conditions (i.e. pH=8.5, H2mdo=3×10?4 mol l?1, Triton X‐114=0.1% (w/v)) the enhancement factors of 65 and 59 and detection limits of 0.14 and 0.2 ng ml?1 were obtained for copper and nickel respectively. The proposed method was applied to the determination of copper and nickel in several natural water samples with satisfactory results.  相似文献   

12.
We studied the separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ), and cadmium(Ⅱ) from magnesium and calcium, using synergistic solvent extraction(SSX) in a typical hydrometallurgical waste solution. A mixture of Versatic 10 acid and Mextral 984 H, diluted with Mextral DT100, was used to obtain fundamental data on p H and distribution isotherms, as well as the kinetics of extraction and stripping. We also investigated the main effects and interactions of common solvent extraction factors: the extraction p H at equilibrium, the temperature, and the extractant concentration. The synergistic effect for extracting metals was confirmed. The results showed that the addition of Mextral 984 H enhanced the separation factors of copper, nickel, cobalt,zinc, and cadmium over magnesium and calcium. Compared with Versatic 10 acid alone, for a mixture of0.5 mol·L~(-1) Versatic 10 acid/0.5 mol·L~(-1)Mextral 984 H, Δp H50 values of copper, nickel, cobalt, zinc, and cadmium were found to be N 2.0, 3.30, 2.85, 0.95, and 1.32 p H units, respectively. The Δp H_(50)(Zn–Mg)and Δp H_(50)(Zn–Ca)values were 3.27 and 2.25, respectively, indicating easy separation and recovery of copper, nickel, zinc, cobalt,and cadmium. The extraction and stripping of copper, cobalt, zinc, and cadmium were fast, with 90% of the metal transferred in 2 min. We next studied whether the metals could be stripped from the extracted liquid selectively in sequence, by using sulfuric acid at different concentrations. The influence of the molecular structure of the oxime and carboxylic acid components upon the synergistic effects was identified by numerical analysis.Excellent separation of copper, nickel, cobalt, and zinc over magnesium and calcium was achieved with this synergistic solvent extraction system.  相似文献   

13.
采用盐酸搅拌浸出-N902萃取工艺回收铜渣氯化烟尘中的铜,考察了影响铜渣氯化烟尘浸出的主要因素. 结果表明,在盐酸浓度15%(w)、液固比4 mL/g、60℃的条件下浸出1 h,铜浸出率可达98.95%,铁、锌、镍浸出率分别达91.58%, 95.8%和93.66%,铅浸出率为5.96%. 盐酸浸出可实现铜与铅的有效分离. 萃取剂N902对浸出液中的铜具有较好的萃取选择性,振荡时间120 s、相比为1、N902浓度30%和pH=3.0的条件下,浸出液铜浓度由7.4 g/L降至0.11 g/L,回收率达98.51%,浸出液中Fe, Zn, Ni和Pb萃取率均不高于1.5%.  相似文献   

14.
《分离科学与技术》2012,47(6-7):1007-1019
ABSTRACT

A liquid-liquid extraction procedure was used to study the amounts of Zn2+ and Cu2+ that could be simultaneously extracted from aqueous solution with di(2-ethylhexyl) phosphoric acid (DEHPA) and LIX 984 diluted with n-heptane at equilibrium. LIX 984 is a 1:1 volume blend of LIX 860 (5-dodoecylsalicylaldoxime) and LIX 84 (2-hydroxy-5-nonylacetophenone oxime). At equilibrium, a 0.3 mol/L DEHPA-20% (v/v) LIX 984 solution extracted 99% of both the zinc and copper from a solution that had 100 ppm of each metal.

A polysulfone hollow-fiber membrane module with 1 mm ID and 5,000-molecular weight cutoff was used to study the amounts of Zn2+ and Cu2+ that could be simultaneously extracted with a mixture of DEHPA and LIX 984. The aqueous and organic streams were operated at 100% recycle. With a 0.6 mol/L DEHPA-10% (v/v) LIX 984 solution, a 90.5 ± 1.7% (s.d.) extraction of zinc and a 93.70 ± 0.79% (s.d.) extraction of copper was obtained after 180 min.  相似文献   

15.
16.
ABSTRACT

The effects of the aqueous phase pH and the organic phase HDNNS concentration on the distribution coefficients of Ni and Fe in pure HDNNS or mixed LIX63-HDNNS systems have been investigated. With the mixed extractants, there is antagonistic extraction of iron below pH 1.4 whereas synergistic extraction occurs above this pH. At pH 2.5 and a fixed LIX63 concentration, iron distribution increases markedly in comparison with the oxime-free system and goes through a maximum with increase in HDNNS concentration. A similar behavior is shown by nickel at both pH 1.0 and 2.5. The log DFeversus pH plot gives a curve with a slope of two for the LIX63-HDNNS mixed system, which suggests that iron is extracted in the form of a species with an ionic charge of 2, probably Fe(OH)2+. The extracted complexes are proposed as Ni(H2L)3D2where all three oxime molecules function as bidentate ligands, and Fe(OH) (H2L) 3D2where one of the oxime molecules functions as a monodentate ligand. The Ni/Fe selectivity is high at low pH and changes mainly as a result of variations in the nickel distribution coefficient, but it is low at high pH because of the synergistic extraction of iron.  相似文献   

17.
Separation of cobalt and nickel from sulfate media was investigated, using a extraction system of 30% 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507)+15% trioctyl/decylamine (N235)+55% sulfonated kerosene. About 41 wt% Co2+ was extracted with 1.6 wt% co-extraction of Ni2+ at O/A ratio of 2:1. Scrubbing of Ni2+ and stripping of Co2+ could be achieved from the loaded organic phase, using water and 0.05 mol/L H2SO4, respectively. Cobalt extraction percentage decreased with increasing Mg2+ concentration, but this influence was negligible as [Mg2+] < 0.1g/L. The favorable equilibrium pH was 4–4.8. A different E-pH curve was observed in the P507-N235 system compared to the saponified P507 system.  相似文献   

18.
以对环境友好的过氧化氢作为氧化剂对镀镍铜板进行退镍处理,代替传统的硝酸溶液.通过正交试验考察了过氧化氢、六次甲基四胺、柠檬酸钠和过氧化氢稳定剂(由质量比1:1的硅酸钠和氯化镁组成)的质量浓度对退镍速率的影响,用金相显微镜观察了退镍后铜板的表面状态.结果表明,在55°C、pH为4的条件下,在含60 g/L过氧化氢、12 ...  相似文献   

19.
铁氧体法去除废水中的镍、铬、锌、铜离子   总被引:2,自引:0,他引:2  
采用铁氧体法处理含镍、铬、锌、铜的废水,研究了pH及硫酸亚铁投加量对重金属离子去除效果的影响.对于镍、锌、铜离子,最佳絮凝pH分别为8.00~9.80、8.00~10.50和10.00,投加的亚铁离子与其摩尔比均为2~8;六价铬的最佳还原pH为4.00~5.50,最佳絮凝pH则为8.00~10.50,最佳投料比为20....  相似文献   

20.
《分离科学与技术》2012,47(9):1402-1408
Quaternary amine could be used to extract uranium from alkaline leach solutions, but third phase formation prevented its application. In this paper, isodecanol was used as the modifier for Aliquat 336 in Shellsol D70 to extract uranium from a carbonate leach solution. The formation of third phase was eliminated. More than 98% of uranium was extracted using 3% (w/v) Aliquat 336 and 3% (w/v) isodecanol in Shellsol D70 from a carbonate leach solution containing 95 mg/L U and 25 mg/L V at pH 10.3 and room temperature in a single contact. The separation factor of uranium over vanadium increased with increasing pH of the auqueous solution and reached 280 at pH 11, indicating a good separation of the two metals. The co-extracted vanadium was scrubbed from the loaded organic solution at pH 11 using a solution containing 50 g/L Na2CO3. Over 90% of uranium was stripped from the loaded organic soluiton using an acidic solution containing 150 g/L ammonium sulphate in a single contact. It was also found that to obtain high uranium extraction, the chloride concentration should be controlled to less than 1 g/L in the aqueous phase.  相似文献   

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