煤油体系中采用D2EHPA,EHEHPA,CYANEX 272从硫酸介质中萃取钒(IV)的机理及热力学(英文)

采用有机磷类萃取剂—D2EHPA,EHEHPA和CYANEX 272在煤油体系中从硫酸介质中萃取钒(IV)。考察溶液pH值、萃取剂浓度、钒离子浓度、温度对钒萃取性能的影响,并确定萃合物的组成。结果表明:随着水相pH值、萃取剂浓度和温度的升高,钒(IV)的分配比增大。D2EHPA可以在更低的pH值下萃取钒(IV),表明其对钒的萃取能力大于EHEHPA和CYANEX 272。萃取机理研究结果表明:3种有机磷类萃取剂对钒的萃取均符合离子交换机理,在低pH值条件下萃合物组成为VOR2(HR)2,在高pH值下萃合物组成为VOR2(R表示萃取剂)。     

β-二酮与CYANEX923或LIX84I混合萃取剂从氨性体系中协同萃锌(英文)

研究β-二酮(HA)与CYANEX923或LIX84I的混合萃取剂在氨性溶液中的萃锌行为;系统讨论有机相萃取剂浓度、水相pH、总氨浓度、温度和阴离子等对萃取性能的影响,从锌萃合物及β-二酮萃取剂结构方面讨论2个混合萃取体系的协同萃取机理。结果表明,HA与CYANEX923混合比与LIX84I混合具有更加明显的协同效应;水相pH和总氨浓度的升高均使萃取性能降低,因为升高pH或氨浓度会促使锌氨配合物的生成,降低水相自由锌离子的浓度,但HA与CYANEX923混合体系在较高pH或总氨浓度下仍具有明显的萃取性能;不同阴离子对HA与CYANEX923混合萃取体系的性能没有明显影响,但在HA与LIX84I混合萃取体系和单独使用HA萃取过程中以(NH4)2SO4NH4NO3NH4Cl顺序降低。     

D2EHPA萃取法从钒页岩高氯浸出液中制备钒电解液（英文）

提出一种从钒页岩中回收有价元素并制备钒电解液的工艺。结果表明，在料液pH值为2.6、萃取剂D2EHPA浓度为20%、相比(O/A)为1:1、萃取时间为8 min、H₂SO₄浓度为4 mol/L及反萃时间为30 min的条件下，钒萃取率为99.3%，反萃率为99.8%。对制备的电解液组成及电化学性能进行详细研究。溶液化学和红外光谱分析表明，浸出液中氯离子可以与钒离子络合，促进钒的萃取。采用本研究提出的工艺能实现钒页岩的综合利用，并避免钒电解液制备过程中有害物质对环境的潜在污染。     

硫酸介质中2-乙基己基膦酸单(2-乙基己基)酯萃取镁的机理

研究了用2-乙基己基膦酸单(2-乙基己基)酯-仲辛醇-磺化煤油组成的有机相从硫酸介质中萃取镁的行为, 考察了水相pH值、萃取剂和SO2-4浓度等因素对萃取的影响, 并采用斜率法和红外光谱法确定了萃合物的组成及萃取平衡的机理. 结果表明 镁的萃取随平衡pH值的增大而显著提高, 亦随萃取剂浓度增大而增加, 且与SO2-4浓度无关, 萃取过程的机理为阳离子交换机理, 萃合物为MgA2*3HA, 表观萃取平衡常数KMg=10-6.73.     

石油亚砜Ⅱ（2）萃Pd（Ⅱ）机理的研究

研究在盐酸介质中石油亚砜Ⅱ(2)萃Pd(Ⅱ)的机理,并分析水相中影响(Ⅱ)萃取的主要因素及其原因,考察不同盐酸浓度下亚砜的萃合方式,盐酸浓度的萃钯(Ⅱ)实验曲线及其对贵金属萃取分离的意义,还测定了萃合物组成.     

盐酸介质中异戊基苯并噻唑亚砜萃取Pd(Ⅱ)的机理

合成了异戊基苯并噻唑亚砜(ABSO),研究了盐酸介质中ABSO萃取Pd(Ⅱ)的机理。考察水相H 浓度和萃取剂浓度对钯萃取的影响,采用斜率法、红外光谱和核磁共振H谱法确定了萃合物的组成及萃取平衡的机理。结果表明:低酸度条件下,H 浓度对钯的分配比无影响,ABSO以中性配位萃取机理萃取Pd(Ⅱ),并通过苯并噻唑环上的氮原子与Pd(Ⅱ)配位形成萃合物PdCl2(ABSO)2。     

二（2-乙基己基）膦酸萃取不同介质中Pr^3＋的研究

研究了二（2-乙基己基）膦酸（PIA-8）的庚烷溶液分别在高氯酸钠、氯乙酸、柠檬酸介质中对pr^3＋的萃取。探讨了萃取平衡时间、不同介质、PIA-8浓度对萃取Pr^3＋的影响及反萃剂浓度对反萃率的影响；斜率法确定了萃合物的组成为Pr（HA2）3；测定了La^3＋、Ce^3＋、pr^3＋、Nd^3＋、Sm^3＋、Eu^3＋在不同介质中的半萃取pH值，在高氯酸钠介质中分别为3．55、3．19、3．02、2．98、2．61、2．43：在氯乙酸介质中分别为3．65、3．27、3．12、3．08、2．66、2．50；在柠檬酸介质中分别为4．34、4．26、4．11、3．91、3．57、3．38。     

亚砜KSO萃取Pd（Ⅱ）的机理

在前文（１）证实亚砜（ＫＳＯ）与ＰｄⅡ）形成萃合物为双核ｔｒａｎｓ－（ＰｄＬｃｌ２）２的基础上考察氢离子浓度、氯离子浓度以及亚砜ＫＳＯ浓度对萃取分配比的影响，推测了ＫＳＯ萃了Ｐｄ（Ⅱ）的机理。     

用石油亚砜（PSO—1）从氯化物溶液介质中萃取Rh（Ⅲ）的机理

以石油亚砜(PSO-1)为萃取剂,从氯化物水溶液介质中萃取Rh(Ⅱ).应用化学平衡及萃取动力学讨论Rh(Ⅲ)与PSO形成的萃合物组成,证明PSO萃取Rh(Ⅲ)为动力学一级反应,还用红外光谱进一步证实萃合物的存在.     

2—乙基己基膦酸单（2—乙基己基）酯—Mn萃合物的研究

通过固态萃合物2-乙基己基膦酸单(2-乙基己基)酯(HEH(EH)P,HA)-Mn的制备,对单烷基膦酸酯萃取二价Mn离子的萃合物组成及萃取机理进行了研究。结果表明:萃合物为不含水分子,组成为MnA_2,属高旋弱场配合物;认为萃合物为四面体结构。     

Selective extraction of zinc from sulfate leach solution of zinc ore

1　INTRODUCTIONSolventextractionwasregardedasahighlyeffi cienttechniqueofseparationandpurification .Ithasbeenwidelyappliedinmetalextractionandrecoveryduringhydrometallurgicalprocessandenvironmentalprotection[14 ] .Solventextractionhasbeencommer ciallyusedintheextractionofuranium ,rarenoblemetals ,copper ,cobaltandnickel,whichwastypical lypresentedbythetechniqueofleach solventextrac tion electrowinning .Presently ,thecopperproductionfromsolventextractionhasbeenaccountedformorethan 2 0 %oft…     

Extraction and stripping of Cu and Ni from synthetic and industrial solutions of Sarcheshmeh Copper Mine containing Cu,Ni, Fe and Zn ions

The extraction and stripping of Cu and Ni ions from synthetic and industrial solutions of Sarcheshmeh Copper Mine containing Cu (770 mg/L), Ni (3200 mg/L), Fe (800 mg/L) and Zn (200 mg/L) were comprehensively investigated using D2EHPA, LIX 984, Cyanex 302, Chemorex CP 150 and Acorga 5774 diluted in kerosene. The influential parameters such as mixing speed and time, concentration of extractant, pH and temperature were considered in extraction stage. Furthermore, stripping of Cu and Ni was examined using different inorganic and organic acids (sulfuric, hydrochloric, nitric and citric acids) with different concentrations. The results indicated that the highest extractions of Cu and Ni occurred within 3 min, with the mixing speed of 500 r/min, 28 °C and A/O ratio of 1:1. Moreover, Cu was extracted by LIX 984 at the concentration of 10% (v/v), whereas Ni was extracted by Cyanex 302 at the concentration of 30% (v/v), efficiently. The optimal pH for Cu and Ni extraction is in ranges of 2−3 and 4−5, respectively. Cu and Ni were selectively extracted with the recoveries of 85%, 93% and 77%, 82% from synthetic and industrial solutions containing Ni, Cu, Zn and Fe ions, respectively. The results of optimal condition showed that 96% of Ni and 93% of Cu were stripped from the synthetic and industrial solutions. Finally, four elements Zn, Fe, Cu and Ni were extracted in three stages with D2EHPA, LIX 984 and Cyanex 302 extractants respectively with the least impurities.     

Separation of Indium and Iron from Dilute Sulphate Solutions with a Phosphorous Mixer Extractant

In the conventional process [l], indium couldbe seParated from some bi-valence metals whileimpurity Fe' tha was most difficult to be sepa-rated was co-extfacted. When the extraCtion ofIn3 from lowly acidic solotions with D2EHPAas eXtfactani was carried ollt, the organic phasewas easily emulsified. FUrthermore, sttippingwas carried out difficultly and a high concelltfa-tion of striPping agent was required. IInPurityFe3 co-extracted with In3 into the organic phasecould not be strtheed …     

Solvent extraction of vanadium from sulfuric acid solution

The behaviour of vanadium(V) extracted from sulfuric acid solution was investigated using Cyanex 923 as an cxtractant. The effects of the concentration of Cyanex 923 and the pH of the solution were studied. The extraction of vanadium(V) increases with the increase of Cyanex 923 concentration and shaking time. Cyanex 923 can extract vanadium(V) fi'om sulfuric acid solution at low pH conditions, and the best pH conditions for exuaction of vanadium(V) are at pH 1.0-2.0. The species extracted into the organic phase is VO2HSO4 with one molecule of Cyanex 923. Equilibrium studies were used to assess the extraction efficiency of vanadium(V) recovery from the sulfuric acid solution.     

V(Ⅴ)-Fe(Ⅲ)-S(Ⅵ)-H2O系热力学研究与钒铁分离方法理论

针对酸浸液钒铁分离的难题,绘制298 K时V(Ⅴ)-Fe(Ⅲ)-S(Ⅵ)-H2O系中存在的各种离子随pH以及浓度变化的热力学平衡图,全面分析钒、铁物种随pH和钒、铁、硫浓度的变化规律,在此基础上提出相应的钒铁分离方法并进行理论分析。结果表明:强酸条件(?1相似文献   

Study on Gold (Ⅰ) Solvent Extraction from Alkaline Cyanide Solution by TBP with Addition of Surfactant

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎ１９７０′ｓ，ｍａｎｙｒｅｓｅａｒｃｈｅｒｓｂｅｇａｎｓｔｕｄｙｏｎｇｏｌｄ（Ⅰ）ｅｘｔｒａｃｔｉｏｎｆｒｏｍａｌｋａｌｉｎｅｃｙａｎｉｄｅｓｏｌｕｔｉｏｎ［１，２］，ｂｕｔｉｔｗａｓｉｎｔｅｒｕｐｔｅｄｄｕｅｔｏｔｈ...     

Removal and recovery of titanium (IV) from leach liquor of high-sulfur bauxite using calcium alginate microspheres impregnated with di-(2-ethylhexyl) phosphoric acid

In the leaching solution of high-sulfur bauxite roasted by sulfuric acid, a high concentration of aluminum presented along with titanium and iron. The present work was to remove Ti(IV) from the leach liquor by calcium alginate microsphere sorbent material (CA-P204) based on natural alginate impregnated with di-(2-ethylhexyl) phosphoric acid (D2EHPA) to purify leaching solution. Cation exchange and chelation make major contributions to the adsorption mechanism according to Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis. The results showed that Ti(IV) was successfully removed by the CA-P204 adsorbent from the Ti(IV)?Al(III)?Fe(III) ternary system with a dynamic column experiment. The removal rate of titanium was nearly 95% under optimal conditions and the maximum adsorption capacity was 66.79 mg/g at pH 1.0. Reusability of CA-P204 was evaluated over three consecutive adsorption/desorption cycles. The adsorption process was simple, low-cost, and had no waste discharge, suggesting that the CA-P204 was promising, efficient, and economical for removing Ti(IV) from high-sulfur bauxite leaching solution.     

Selective separation of Cu(II), Zn(II), and Cd(II) by solvent extraction

An experimental investigation was presented on the separation of Cu (II), Zn (II), and Cd (II) from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LIX 984N is highly selective and very efficient in the extraction of Cu (II), and the analysis of variance indicates that the sequence of parameters according to their influence on the separation efficiency is phase ratio>LIX 984N concentration>pH value>extraction time. The optimal condition for copper extraction is obtained as 25% of LIX 984N concentration, 7 min of extraction time, 3:2 of phase ratio O/A, and pH=1.7. The separation of Zn (II) and Cd (II) was performed after the copper extraction from the raffinate. Comparative analysis of the separation with di-2-ethylhexyl phosphoric acid (D2EHPA), D2EHPA-tributyl-phosophate (TBP) synergistic extracting system, and 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester (HEHEHP) was made at pH=2.0. It is demonstrated that the extraction efficiency with D2EHPA is improved after being saponified by sodium hydroxide, and D2EHPA-TBP synergistic extracting, as well as HEHEHP, has a superior selectivity to Zn (II) over Cd (II).     

新混合萃取剂体系的萃取动力学和胶团化作用SCIEI

本文研究了协同萃取体系(D_2EHPA-H_2RPA-Al^(3+))的胶团化作用和界面特性[H_2RPA为长碳链单烷基磷酸脂,D_2EHPA为二(2—乙基己基)磷酸],以及液—液界面动力学。结果发现,混合体系中H_2RPA具有较强烈的胶团化作用和较高的界面活性,随着[D_2EHPA]的增加,其胶团化倾向和界面活性随之下降,H_2RPA和D_2EHPA具有完全相反的界面吸附行为,证实了非胶束混合萃取体系的动力学控制机制为界面化学反应控制型,得到了反应速率方程式,非胶束体系为有应用前景的混合萃取剂体系。