Recovery of Copper from a Waste Heat Boiler Dust Leach Liquor using LIX 84I and LIX 622N

The dust collected from the waste heat boiler of a copper plant was leached with sulfuric acid and the leach liquor contained 31.63 kg/m³ Cu, 14.78 kg/m³ Fe, 2.21 kg/m³ Zn, 0.26 kg/m³ Co, 0.09 kg/m³ Ni, and 0.23 kg/m³ Cd. The iron content in the leach liquor was precipitated out using Ca(OH)₂ and from the filtrate copper was extracted with the extractants LIX 84I and LIX 622N in kerosene. Extraction of copper with either extractant increased with increasing equilibrium pH and extractant concentration. The McCabe-Thiele plots for quantitative extraction of copper indicated 3-stages at O:A ratio of 3:2 with 30% extractants. The counter-current extraction study showed 0.21 kg/m³ and 6.77 g/m³ copper in the third stage raffinates of LIX 84I and LIX 622N indicating 98.64% and 99.95% extraction, respectively. For extraction of a mole of copper ion, two moles of the extractant was required to release two moles of hydrogen ion to the aqueous phase. The quantitative stripping of copper from the loaded organic phases of LIX 84I and LIX 622N with 180 kg/m³ H₂SO₄ was possible in 3-stages at O:A ratio of 3:1 and 3:2, respectively. The thermodynamic parameters such as ΔH, ΔG, and ΔS were calculated for both the systems. The enthalpy change (ΔH) values were positive for extraction of Cu with either extractant indicating the processes to be endothermic. The IR spectra indicated the association of phenolic-OH group of oxime molecules in the formation of copper complexes.     

Extraction of vanadium(V) from sulfate solutions by ACORGA M5640

ACORGA M5640 (hydroxy‐oxime derivative) has been applied as an extraction reagent for vanadium(V) from sulfate media. The extraction system was studied as a function of contact time, temperature, aqueous pH, diluent of the organic phase, and metal and extractant concentrations. The extraction reaction is endothermic and it is dependent on the organic diluent, aqueous pH and extractant concentration. The data have been analysed numerically to determine the stoichiometry of extracted species and their equilibrium constants. It was found that vanadium was extracted into the organic phase by a complex mechanism which involves the formation of two species (VO₂R and VO₂R. HR, where R represents the extractant). Vanadium stripping by acidic and ammonium hydroxide solutions was also studied. Copyright © 2003 Society of Chemical Industry     

Extraction of zinc from ammoniacal/ammonium sulphate solutions by LIX 54

The extraction of zinc from ammoniacal/ammonium sulphate aqueous media using LIX 54 has been studied. The metal extraction rate has been examined and also the effect of temperature on the extraction of zinc (ΔH° = −8·8 kJ mol⁻¹). The effect of the aqueous pH, and therefore zinc ammine complex formation, on the extraction of zinc was studied. Stripping of the metal from loaded organic phases was carried out at various rates, temperatures (ΔH° = 3·2 kJ mol⁻¹) and sulphuric acid concentrations. The results obtained were compared with others obtained from the literature wherein different extractants were used. © 1998 SCI.     

用磷酸三丁酯萃取分离硫酸铵母液中的HCN

研究了磷酸三丁酯(TBP)-磺化煤油体系从重庆某企业甘氨酸生产副产物硫酸铵母液中萃取分离HCN的工艺,考察了萃取体系、TBP体积分数、母液初始pH值、相比(Vorg∶Vaq)对萃取HCN的影响以及氢氧化钠浓度、相比(Vaq∶Vorg)和平衡pH值对HCN反萃的影响。结果表明:选用TBP作为萃取剂能够对硫酸铵母液中的HCN进行快速有效的萃取;TBP体积分数、母液初始pH值及相比对HCN萃取率影响显著;以含体积分数35%TBP的有机相作萃取剂,在相比(Vorg∶Vaq)为2∶1的条件下,pH值为2.92的含氰1.71 g/L的硫酸铵母液经3级错流萃取,萃余液中含氰低于0.5 mg/L,氰的萃取率接近100%;在相比(Vaq∶Vorg)为1∶1条件下,以0.6 mol/L的氢氧化钠为反萃液,控制反萃液平衡pH值大于13.0,氰的单级反萃率大于96%;含氰0.78 g/L的有机相在相比为1∶1条件下,经过2级错流反萃,氰基本上被反萃完全,贫有机相不经过处理可循环使用。     

Recovery of copper from ammoniacal/ammonium sulfate medium by LIX 54

The extraction‐stripping reaction of Cu(II) by LIX 54 in Iberfluid from aqueous ammonium sulfate medium at pH 8.5 has been investigated. The effects of pH, metal ion, extractant concentration as well as the loading capacity of the reagent were studied. The extraction equilibrium constant for copper was determined numerically to be 7 × 10⁻⁷. Experimental data can be explained assuming the formation of CuR₂ species in the organic phase (R represents the extractant). Copper stripping was studied using typical spent copper electrowinning solutions as stripping medium. The number of stages required for the extraction and stripping of copper was also evaluated. The results were used to asses the conditions for purification of industrial waste solutions (eg spent etchants) containing copper through counter‐current extraction‐stripping. © 1999 Society of Chemical Industry     

Extraction and separation of molybdenum(VI) from acidic media by fatty hydrazides

BACKGROUND: The increasing demand for molybdenum has encouraged the development of low‐cost and environmentally friendly extractants to recycle and recover this metal. In the present study, solvent extraction of Mo(VI) from acidic media using a mixture of fatty hydrazides synthesised from palm olein as the extractant was carried out. The effects of various parameters such as acid, diluent, contact time, extractant concentration, metal ion concentration and stripping agent and the separation of Mo(VI) from other metal ions such as Co(II), Ni(II), Al(III) and Mn(II) were investigated. RESULTS: It was found that the extraction of Mo(VI) into the organic phase involved the formation of 1:3 complexes. Mo(VI) was successfully separated from commonly associated metal ions such as Ni(II), Co(II), Al(III) and Mn(II). Mo(VI) stripping from the loaded organic phase was studied using different acidic and alkaline solutions and was found to be optimal with ammonium hydroxide solution. CONCLUSION: These results are useful for the development of a method to recover Mo(VI) from acidic media utilising fatty hydrazides as the extractant. Copyright © 2008 Society of Chemical Industry     

Solvent extraction of gold by LIX 79: experimental equilibrium study

The extraction of gold(I) from aurocyanide aqueous solutions using LIX 79 has been studied. Different variables that could affect the extraction system were evaluated: equilibration time, aqueous pH, metal and extractant concentrations, organic phase diluent and aqueous ionic strength. The extraction of the aurocyanide complex with respect to other metal‐cyano complexes has also been studied on both synthetic and real leach solutions. Gold experimental data have been analysed numerically to determine the stoichiometry of extracted species and its equilibrium constant. It was found that gold(I) was extracted into the organic phase by the formation of the species RHAu(CN)₂ (LIX 79=R). Stripping of gold from loaded organic phases was carried out using NaOH or NaCN solutions. © 1999 Society of Chemical Industry     

Palladium Extraction from Nitric Acid Solutions by LIX 84 and LIX 860-I

ABSTRACT

The extraction of Pd(II) from weakly nitric acid solutions by LIX 84 (2-hydroxy-5-nonylacetophenone oxime) and LIX 860-I (5-dodecylsalicylaldoxime) dissolved in toluene has been studied and compared from the viewpoint of extraction equilibria. The effects of pH, nitrate ions and metal and extractant concentrations on the palladium distribution ratio have been quantified. The extraction rate of Pd(II) from this media is slow but the metal is quantitatively extracted by adding just the stoichiometric amount of the extractants. The experimental data have been treated graphically and numerically by means of the Letagrop-Distr program and can be explained by assuming the formation of the chelate PdL₂. Values of the extraction constants are also given.     

Copper Solvent Extraction from Waste Cyanide Solution with LIX 7820

The use of a solvent mixture of a quaternary amine and nonylphenol (LIX 7820) to extract copper cyanide from waste cyanide solution has been studied. Copper extraction is favorable at low pH, whereas a high cyanide‐to‐copper ratio tends to suppress copper loading. The preferential extraction of Cu(CN)₃ ^2? over Cu(CN)₄ ^3? and CN^? has been confirmed by the examination of both the extraction of copper and cyanide by the solvent mixture under different experimental conditions. The solvent mixture also strongly extracted zinc and nickel from the cyanide solution, but it exhibits weak affinity for iron cyanide complex and free cyanide. The important findings suggested the potential application of the solvent mixture for the recovery of copper and cyanide from waste cyanide solutions, by which copper can be extracted and concentrated into a small volume of solution and the barren cyanide solution recycled to the cyanidation process.     

Fundamental aspects of the extraction and stripping of palladium by LIX 65N

The fundamental aspects of the extraction and stripping of palladium from its chloride solution by LIX 65N diluted with Kermac 470B have been studied. Equilibria of extraction and stripping, temperature effect, the variation of sodium thiosulphate concentration on stripping and rate of extraction and stripping on the system Pd²⁺-LIX 65N-Kermac 470B are reported. The fundamental aspects of the extraction and stripping of palladium from its chloride solution by LIX 65N diluted with Kermac 470B have been studied. Equilibria of extraction and stripping, temperature effect, the variation of sodium thiosulphate concentration on stripping and rate of extraction and stripping on the system Pd²⁺-LIX 65N-Kermac 470B are reported.     

TBP对LIX84由Cu2+-NH3-Cl——H2O系萃取铜及氨的影响

以Cu2+-NH3-Cl--H2O氨性溶液为被萃水相,在LIX84中添加磷酸三丁酯(TBP),考察了有机相中TBP浓度、被萃水相铜离子浓度、总氨浓度和pH值及相比、LIX84浓度对铜萃取率、共萃氨量的影响. 结果表明,随LIX84中TBP浓度升高,铜萃取率变化不大,负载有机相的共萃氨量明显降低. 有机相中TBP浓度为0.1 mol/L、LIX84浓度为40%、被萃水相铜离子浓度25 g/L、总氨浓度3 mol/L及pH值9.1、相比1:1、萃取时间30 min时,铜萃取率约为81%,与未添加TBP时基本一致,而负载有机相的共萃氨量由未添加TBP时的260 mg/L降至添加TBP后的85 mg/L.     

Co-extraction and selective stripping of copper (II) and molybdenum (VI) using LIX 622

LIX 622 diluted with kerosene was used to co-extract copper (II) and molybdenum (VI) from acidic sulphate solutions. The influence of equilibrium pH and extractant concentration on metal co-extraction has been studied. The extraction of both metals is sensitive to equilibrium pH; however, molybdenum is extracted preferably to copper at acidic pH values. For aqueous phases containing both metals, conditions were established for the co-extraction, selective stripping of copper and molybdenum and NH₃ removal from the stripped organic solution.     

Solvent extraction with LIX 973N for the selective separation of copper and nickel

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     

Separation of Simulated Mixed Mo(VI) and V(V) From HNO3 and HCl Solutions by Selective Extraction and Stripping with Tri-N-Butyl Phosphate as Extractant

Equilibrium study was carried out to determine the optimum conditions required for Mo(VI) extraction from HNO₃ solutions and subsequently, simulated mixed Mo(VI), and V(V) were extracted from HNO₃ (pH = 1.0) and 6.0 mol L^?1 HCl solutions with TBP dissolved in n-hexane. The variation of pH (selective extraction) and selective stripping were investigated as methods of separation of Mo(VI) and V(V). The latter method was found inefficient for separations from HNO₃ solutions (pH = 1.0) except supplemented with selective stripping (back-extraction with 2.0 mol L^?1 H₂SO₄/14.5 mol L^?1 NH₄OH). While from 6.0 mol L^?1 HCl, selective stripping was adequate to quantitatively strip in turns the Mo(VI) and V(V) co-extracted into the TBP phase. About 100% of the co-extracted V(V) from the HCl medium was stripped in a two-stage process, in contrast to a single-stage required for Mo(VI) of the same result. The selective stripping method was found to be better because an initial appreciable co-extraction had occurred prior to stripping separation. Based on analytical and spectra data, the extracted complexes from HNO₃ and HCl media were formulated as ((MoO₂)_7–8n(VO₂)_2n · (NO₃)₁₆) ^(16–18)n- · m TBP (where n>m) and (MoO₂Cl₂ · VO₂ Cl) · xTBP, respectively.     

Experimental and Theoretical Investigation of Distribution Equilibria and Kinetics of Copper(II) Extraction with LIX 84 I and TFA

Batch experiments of copper(II) extraction at equilibrium were carried out in a temperature controlled stirred cell to extract copper(II) with LIX 84-I and 1,1,1-trifluoro-2,4-pentanedione (TFA) diluted in either n-heptane, tetradecane, MIBK, or n-decanol at 298 and 313 K. Extraction efficiency and capacity of copper(II) extraction with acid extractants at equilibrium were measured and analyzed using a theoretical model based on equilibrium extraction kinetics. Experimental and theoretical investigations revealed that TFA and n-decanol are found to be an efficient extractant and diluent, respectively, for copper(II) extraction with high values of extraction capacity.     

逆向浸取法制取硫酸镁、氢氧化镁及氧化镁

介绍了以硫酸铵、白云石为原料制备硫酸镁、氢氧化镁、轻质氧化镁的实验条件及工艺过程。讨论了实验条件对产品质量、性能的影响。与白云石的开发利用其它工艺比较，该方法具有原料来源方便、生产成本较低等优点，无三废污染，废渣可加工成CaSO4产品，所排氨气也可回收利用。     

由硫酸铵溶剂萃取法制备硫酸钾工艺研究

通过在反应体系中加入难溶于水的有机溶剂,对硫酸铵和氯化钾制备硫酸钾的溶剂萃取工艺进行了研究。以氧化钾收率为评价指标,确定其工艺条件为:反应时间120 m in,反应温度45℃,萃取剂用量以不超过90%(质量分数)为宜,固液比22%左右,配料比1.85左右。对硫酸钾产品进行质量分析,表明其达到农用一级品标准。     

Extraction equilibria of chromium(VI) from sulfuric acid solutions with tri-n-octylphosphine oxide

The extraction equilibria of chromium(VI) from sulfuric acid solutions with tri-n-octylphosphine oxide (TOPO) dissolved in kerosene at 25°C have been studied. The possible complexes of chromium(VI) with TOPO in organic phase and extraction constants were determined by best fitting the distribution coefficient expression of Cr(VI) with experimental data using the Rosenbrock method. The extraction reactions, including the equilibria among seven species in aqueous phase (H₂CrO₄, HCrO₄⁻, HCr₂O₇⁻, Cr₂O₇²⁻, CrSO₇²⁻, HSO₄⁻ and SO₄²⁻) and five possible complexes in organic phase (H₂CrO₄·(TOPO), H₂Cr₂O₇·(TOPO)₃, H₂CrSO₇·(TOPO)₃, H₂SO₄·(TOPO)₂ and (H₂SO₄)₂·(TOPO)₂) were proposed. The influence of initial sulfuric acid concentration on the fraction of extracted complexes and on the distribution coefficients of Cr(VI) is discussed. This result was helpful for the clarification of the extraction reactions of Cr(VI). © 1998 Society of Chemical Industry     

SOLVENT EXTRACTION OF MOLYBDENUM (VI) WITH LIX 63

The equilibrium and kinetics of the extraction of molybde-num(VI) with LIX 63 was investigated. The extraction of Mo(VI) is both favored by high acidity and high LIX 63 concentration. From the equilibrium studies, the extraction constant for the reaction was found to be log K_ex - 16.43. The rate of extraction is first ex order in both metal and extractant but decreases non-linearly with pH. The rate-determining step of the reaction was deduced to be the formation of a 1:1 complex between Mo(VI) and LIX 63 in the aqueous phase. A mechanism in which different Mo(VI) species react concurrently with the neutral ligand is proposed. The logarithmic values of the second order reaction rate constants (in M^?1 s^?1 units) involving each Mo(VI) species are as follows: molybdate - 2.30, bimolybdate - 5.82, and molybdic acid - 8.16. These results agree well with the results reported for other ligands.     

Separation of cobalt and nickel from acidic sulfate solutions using mixtures of di(2‐ethylhexyl)phosphoric acid (DP‐8R) and hydroxyoxime (ACORGA M5640)

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