Extraction mechanism of cerium（Ⅳ） in H2SO4/H3PO4 system using bifunctional ionic liquid extractants

The extraction of Ce（Ⅳ） in H2SO4/H3PO4 system was investigated systematically using bifunctional ionic liquid extractants（Bif-ILES） [A336][P507],[A336][P204] and [A336][C272] in n-heptane.The effects of H2SO4 concentration,extractant concentration and salting-out agent concentration were observed in detail.The extraction mechanism of Ce（Ⅳ） in H2SO4/H3PO4 system was obtained.The comparison with other extractants such as Cyanex923,TBP was also studied.Thermodynamic functions of the extraction reaction were calculated,showing that the extraction was an exothermic process.The separation of Ce（Ⅳ） from RE（Ⅲ） and Th（Ⅳ） was also investigated.The result indicated that Ce（Ⅳ） could be selectively extracted in this system.CePO4 nanoparticles were obtained in the process of stripping using H2O2 in H2SO4/H3PO4 system.X-ray diffraction（XRD）,scanning electron microscopy（SEM） and spectroscopy were adopted for the characterization of the sample.     

Leaching of a sphalerite concentrate with H2SO4–HNO3 solutions in the presence of C2Cl4

The enhanced leaching of sphalerite concentrates in H₂SO₄–HNO₃ solutions and the extraction of sulfur with tetrachloroethylene were studied. Variables of the process were investigated including leaching temperature, reaction time, liquid / solid ratio, and tetrachloroethylene concentration. The number of cycles that tetrachloroethylene could be recycled did not have a significant effect on zinc extraction. The results indicated that 99.6% zinc extraction was obtained after three hours of leaching at 85 °C and 0.1 MPa O₂, when 20 g of sphalerite concentrate were leached in a 200 ml solution containing 2.0 mol/L H₂SO₄ and 0.2 mol/L HNO₃, in the presence of 10 ml C₂Cl₄. Leaching rates were significantly improved under these conditions.     

Observation in situ dans un met du cisaillement d'un joint de macle coherent Σ3 par une micromacle de deformation

Cu-5.5 at.% Si alloy with low stacking fault energy (γ ≈ mJ/m²) has been strained in situ in a JEOL 200CX transmission electron microscope (TEM) at room temperature. Under these conditions, plastic deformation by perfect dislocations and mechanical microtwinning are two competitive deformation mechanisms. Interactions between partial dislocations of a microtwin and an annealing twin boundary (Σ3 coherent boundary) have been specially investigated. Dynamic observations have shown that deformation propagates through the Σ3 boundary leading to shearings in both Σ3 boundary plane and the mirror plane of the incident microtwin with respect to the Σ3 boundary. Burgers vectors of the dislocations acting on both sids of the Σ3 boundary have been identified, allowing us to suggest a reaction describing the interaction. The reaction is discussed and compared to other published models.     

用SO2H2OH2SO4(NH4)2SO4溶液从印度洋结核中浸出金属

海底结核是许多金属 ,如 Cu、Ni、Co和 Mn的潜在资源 ,这些金属以氧化物或氢氧化物形式存在。Mn和 Fe的主要基体分别是 δ Mn O2 和针铁矿。为了溶解 Mn O2 及其伴生的有价金属 ,必须先将 Mn O2 还原。所用还原剂有 SO2、活性炭和硫酸亚铁等。在常压下 ,用硫酸和活性炭浸出海洋结核 ,铁几乎全部进入溶液 ,给下步工序造成困难。同样 ,用 SO2 水溶液或 SO2H2 SO4介质浸出结核 ,浸出液中铁质量浓度高 ,而铜的回收率低。 R.Acharya等人进行了常压下 ,在 SO2 H2 O H2 SO4(NH4) 2 SO4溶液中 ,浸出 Cu、Ni、Co、Mn及抑制铁溶解的研…     

Extraction mechanism and separation behaviors of low-concentration Nd3+ and Al3+ in P507–H2SO4 system

In order to clarify the solvent extraction and separation behaviors of rare earths and impurity of Al during the extraction and enrichment of low-concentration leach solution of ion-adsorption rare earth ore, the extraction mechanism and separation behaviors of Nd³⁺ and Al³⁺ in the Nd₂(SO₄)₃–Al₂(SO₄)₃ mixed solution using P507 were studied in this work. The extraction of Nd³⁺ and Al³⁺ follows the cation exchange mechanism. With the increase of the equilibrium pH, β_Nd/Al in the extraction of the Nd₂(SO₄)₃–Al₂(SO₄)₃ mixed solution using P507 is always higher than that in the extraction of single Nd₂(SO₄)₃ and Al₂(SO₄)₃ solutions. It can be attributed to the fact that the extraction of Nd³⁺ using P507 is much faster than that of Al³⁺, and Al³⁺ is more prone to be hydrolyzed at lower pH. β_Nd/Al in the extraction of the Nd₂(SO₄)₃–Al₂(SO₄)₃ mixed solution decreases gradually with the increase of mixing time within the equilibrium pH range of 1.5–1.9. The extraction of Nd³⁺ using P507 is much faster than that of Al³⁺, but the stability of Al³⁺-loaded organic phase is better than that of Nd³⁺-loaded organic phase, thus Nd³⁺ in the Nd³⁺-loaded organic phase is gradually replaced by Al³⁺ in the aqueous phase with the increase of mixing time.     

Extraction and Stripping of Ytterbium （Ⅲ） from H2SO4 Medium by Cyanex 923

Ytterbiumand other lanthanide oxides are widelyused in the preparation of optical glasses ,glass fibersfor optical purposes ,gasoline-cracking catalysts ,pol-ishing compounds and carbon arcs , and in the ironand steel industriestoremove sulfur ,carbon ,and oth-er electronegative elements fromiron and steel[1].Themain sources of ytterbiumand other heavy rare earthelements are monazite and bastnasite . Withincreasingdemand for rare earth elements ,the separation andpurification of these elements…     

废旧碳性锌锰电池正极材料在SO2/H2SO4体系中的浸出行为

研究了废旧碳性锌锰电池正极材料中的锌、锰在SO_2/H_2SO_4体系中的浸出行为,考察了浸出时间、SO_2流量、体系pH、搅拌速度、固液质量体积比和浸出温度对锌、锰浸出率的影响。试验结果表明:在SO_2流量0.02 m~3/h、搅拌速度250 r/min、体系pH=1.56、固液质量体积比1 g/10 mL、浸出温度60℃、浸出时间4 h条件下,Zn、Mn浸出率均在99%以上,浸出效果较好。     

La2(SO4)3/SiO2催化合成增塑剂

以La2(SO4)3/SiO2为催化剂,顺丁烯二酸酐和丁醇为原料,合成内增塑剂顺丁烯二酸二丁酯,探讨了催化剂用量,酐醇物质的量比以及反应时间等对收率的影响.结果表明,La2(SO4)3/SiO2对顺丁烯二酸二丁酯的合成具有良好的催化活性,在适宜的条件下其收率可达99%.当把此催化剂用于合成柠檬酸三丁酯、邻苯二甲酸二辛酯、丁二酸二丁酯时,同样具有良好的催化活性.     

Étude de la valorisation de la magnétite titanifère de la région de Magpie,Québec: Partie II — Composition et structure de la fonte et de la scorie obtenues par fusion réductrice d'un concentré magnétique

Abstract

A magnetic concentrate from Magpie titaniferous iron ore has been smelted in a pilot scale arc furnace. A pig iron containing most of the chromium and vanadium of the ore has been obtained, while the titanium remained in the slag. The main phases occurring in this slag are a pseudobrookite-type solid solution, a spinel and several silicates. The composition of pseudobrookite depends on the reducing conditions and can reach 90% TiO₂. The spinel composition is on the MgAl₂O₄ side of the MgAl₂O₄-Mg₂TiO₄ solid solution.

Résumé

Des essais de fusion réductrice au four électrique en présence de carbone, ont été réalisés sur un concentré magnétique du minerai de Magpie. Ce traitement permet d'obtenir une fonte contenant la plus grande partie du chrome et du vanadium, et une scorie titanifere. Cette dernière est constituée d'une pseudobrookite, d'un spinelle et de silicates. La pseudobrookite est une solution solide de composition variable suivant le degré de réduction et titrant plus de 90% en TiO₂. Le spinelle est de composition voisine de MgAl₂O₄.     

SO2-4/TiO2-WO3催化合成丁醛1,2-丙二醇缩醛

以固体超强酸SO2-4/TiO2-WO3为催化剂,对以丁醛和1,2-丙二醇为原料合成丁醛1,2-丙二醇缩醛的反应条件进行了研究.实验表明SO2-4/TiO2-WO3是合成丁醛1,2-丙二醇缩醛的良好催化剂,研究了醛醇摩尔比、催化剂用量、反应时间诸因素对收率的影响.最佳反应条件为n(丁醛)/n(1,2-丙二醇)=1/1.4,催化剂用量为反应物料总质量的0.5%,环己烷为带水剂,反应时间50 min.上述条件下,丁醛1,2-丙二醇缩醛的收率可达84.6%.     

SO2-4/TiO2-WO3催化合成环己酮1,2-丙二醇缩酮

介绍了以固体超强酸SO42-/TiO2-WO3为多相催化剂,通过环己酮和1,2-丙二醇反应合成了环己酮1,2-丙二醇缩酮,探讨了SO24-/TiO2-WO3对缩酮反应的催化活性,较系统地研究了酮醇量比,催化剂用量,反应时间诸因素对产品收率的影响.实验表明:SO24-/TiO2-WO3是合成环己酮1,2-丙二醇缩酮的良好催化剂,在n(环己酮):n(1,2-丙二醇)=1:1.5,催化剂用量为反应物料总质量的1.25%,环己烷为带水剂,反应时间1.5 h的优化条件下,环己酮1,2-丙二醇缩酮的收率可达88.5%.     

复合固体超强酸SO2-4/Fe2O3-MoO3催化合成乙酸辛酯

以硝酸铁和钼酸铵为原料,柠檬酸为络合剂,采用溶胶-凝胶法,制备固体超强酸SO2-4/Fe2O3 MoO3.催化剂制备的最佳条件为:浸泡液浓度为0.5 mol/L,焙烧温度为350 ℃, 焙烧时间为3.5 h.用该催化剂通过正交试验合成乙酸辛酯的最佳条件为:酸醇摩尔比为1.35∶1.0,催化剂用量为0.8 g(以0.15 mol正辛醇为准),带水剂用量为12 mL,反应时间为2.5 h,其酯收率可达95%以上.     

新型固体酸SO2-4/MnO2/γ-Al2O3催化合成草酸二异戊酯

通过浸渍--焙烧法制备了新型固体酸SO(2-)4/MnO2/γ-Al2O3催化剂,以草酸和异戊醇为原料合成了草酸二异戊酯,考察了催化剂的焙烧温度、催化剂用量、原料配比、反应时间、带水剂甲苯用量对反应的影响.最佳的反应条件为:催化剂焙烧温度500℃、催化剂用量1.5g、n(草酸):n (异戊醇)=1:3、带水剂甲苯30mL、回流时间1.5h;在最佳反应条件下,草酸二异戊酯的收率可达99.6%.新型固体酸SO(2-)4/MnO2/γ-Al2O3的催化活性高、产品收率高,后处理简便,无"三废"污染,符合节能环保、绿色催化的发展趋势.     

Rb2SO4-C2H5OH-H2O三元体系的溶解度研究

采用半微量相平衡实验装置，研究了Rb2SO4-C2H5OH-H2O三元体系0-60℃的等温平衡溶解度，发现该体系在实验研究温度范围内饱和溶液相都是不分层的乙醇-水溶液。用TPD软件（三角相图绘图软件）绘制了相应的平衡相图，“Schreinmakers”湿渣结线法确定平衡固相皆为无水Rb2SO4；同时给出了体系10-60℃的等温溶解度方程及30℃时C2H5OH对Rb2SO4的盐析率曲线。