磁场作用下三辛胺萃取钒的机理研究

本文研究了磁场作用下TOA从盐酸溶液中萃取钒的机理。在水相平衡PH3．0时，用饱和法及等摩尔系列法求得萃合比为2．5，用斜率法求得n＝1．5。萃取反应式为：可以认为，磁场作用不改变萃取钒的机理。     

在磁场作用下用乙酰胺萃取五价砷

本文考察了在磁场作用下，用乙酰胺（Ａ１０１）萃取五价砷。结果表明，在磁场作用下，乙酰胺萃取五价砷的能力增大。乙酰胺对工业铜电解液的萃取除砷台架试验表明，经５级萃取，砷的萃取率在９９％以上。在磁场作用下，用乙酰胺萃取可望成为分离砷的有效工业方法。     

酸性含磷萃取剂萃铟机理及性能规律研究

利用斜率法、连续变量法研究了四种酸性含磷萃取剂从稀硫酸溶液中萃取铟的机理，结果表明存在两种萃取机理。测定了各萃取剂萃铟平衡常数、萃合物稳定常数、萃取平衡时间及不同硫酸浓度下的反萃率，在此基础上讨论了萃取剂结构对萃取性能递变规律的影响。     

《湖南冶金》一九八四年总目录

期页 题目期页磁场对有机溶剂萃取稀土元素影响的探索研究21稀散金属的溶剂萃取和离子交换(待续)232火法炼汞热力学分析311关于铜电解过程中胶的作用机理的探讨321稀散金属的溶剂萃取和离子交换(续完)338提高硫铁矿烧渣中金银回收率的途径41T湿法直接制取锑的初探420谈谈湿法炼     

不对称亚砜BSO萃取分离钯、铂的研究

研究了不对称亚砜(BSO)萃取钯、铂的行为及机理。结果表明:酸度对钯、铂的萃取率和萃取机理有很大影响。在低酸度时,BSO萃取钯主要是中性配位萃取机理,对钯的萃取率接近100%,而对铂的萃取率极低;在高酸度时,BSO萃取钯、铂的机理都是离子缔合萃取,且对钯、铂的萃取率均已接近100%。利用BSO在低酸度下萃取钯、铂可以实现钯、铂的有效分离。氨水为钯的高效反萃剂,蒸馏水为铂的高效、经济反萃剂。     

油溶性络合剂LE的合成及其萃取稀土元素的研究

本文用乙胺二四乙酸（EDTA）为主要原料合成了一种油溶性络合剂LE,并对其进行了表征,同时测定了其分子量。研究了LE对稀土元素（Tb、Dy、Ho、Er和Y）的萃取性能,接着对固体配合物的组成与结构进行了分析,最后讨论了LE萃取稀土元素的机理。     

水杨酸介质中开链冠醚对稀土的萃取

研究了开链冠醚1.8—二(8′—羟喳啉)—3.6—二氧杂辛烷(简示为E03—8q),在水杨酸介质中对稀土镧的萃取性能和机理及其对稀土元素的萃取规律性。     

中国含稀土元素的硬质合金研究

对中国含稀土元素的硬质合金１０多年的研究进行了综述，其内容有历史回顾、合金研制、性能和组织结构影响，稀土元素在硬质合金中分布和存在形态，以及稀土元素对合金性能的作用机理讨论。     

长链脂肪酸在硫酸介质中萃取稀土的研究

对C18的长链脂肪酸在硫酸体系中萃取稀土元素进行了研究,测定了15个稀土元素的萃取序列,利用饱和容量法和斜率法对萃取反应机理进行了研究。     

稀土元素对高温钛合金组织和性能的影响

综述了稀土元素在高温钛合金中的作用。主要内容包括稀土元素在高温钛合金中的存在状态及稀土元素对高温钛合金组织、室温及高温性能的影响。归纳总结了稀土元素对高温合金性能影响的机理,并提出了含稀土元素的高温钛合金的设计原则,以期对以后高温钛合金的研究和设计提供帮助。     

Separation of Rare Earths by Solvent Extraction

Abstract

Solvent extraction technology for the separation of rare earths is a recent one. This is mainly due to the low separation factors between the adjacent rare earths for any type of extractants that have been investigated so far. In spite of this inherent weakness arising due to the gradual small changes in basicity in the series of rare earths few extractants have been used on commercial scale for the separation of high purity rare earths. In this paper the mechanisms involved in the extraction of rare earths using different types of extractants like tributylphosphate, di (2-ethylhexyl) phosphoric acid, 2-ethylhexyl 2-ethylhexyl phosphonic acid and quaternary ammonium salts have been discussed. The development of suitable mathematical models of the extraction behaviour of rare earths, particularly for the liquid cation exchangers, and their suitability for the development of the processes for the separation of rare earths is highlighted. Various process parameters that have been optimised using the computer programs developed by incorporating the mathematical models have been used in the purification of rare earths. The flow sheets designed for the separation of various rare earths are also given.     

Extraction and separation of yttrium from other rare earths in chloride medium by phosphorylcarboxylic acids

Two phosphorylcarboxylic acids, 3-((bis(2-ethylhexyloxy))phosphoryl)propanoic acid (PPA) and 3-((bis(2-ethylhexyloxy))phosphoryl)-3-phenylpropanoic acid (PPPA), were synthesized for separating yttrium from other rare earths in the chloride feed of ion-adsorption type rare earth concentrate. The effect of the factors such as pH_1/2, temperature, saponification degree and phase modifiers was investigated. The separation efficiencies of PPA and PPPA are obviously better than the typical extractants such as sec-octylphenoxy acetic acid (CA-12) and naphthenic acid (NA). The extraction process of rare earths by PPA and PPPA is a cation exchanging reaction, which is similar to those of CA-12 and NA. The loaded rare earths in both PPA and PPPA systems can be effectively back-extracted by 0.5 mol/L HCl or higher concentration. A cascade extraction process for separating yttrium from other rare earths was developed using PPPA as the extractant. The yttrium product with the purity of 97.20 wt% was obtained by 35 stages of extraction and 12 stages of scrubbing.     

新型萃取剂Cyanex272在溶剂萃取稀土中的应用

通过新型萃取剂Ｃｙａｎｅｘ２７２同Ｐ２０４和Ｐ５０７的对比预示了Ｃｙａｎｅｘ２７２分离稀土的景，并介绍了近期Ｃｙａｎｅｘ２７２溶剂萃取分离稀土的研究动态，在此基础上提出几点建议。     

富集稀土磷酸溶液中稀土的萃取研究

研究了P204从富集稀土磷酸溶液中稀土元素钇、镧、钕的萃取行为,并考察了初始水相中P_2O_5浓度、萃取相比、萃取剂浓度、萃取时间对稀土萃取效果的影响。结果表明,低磷酸浓度、较大相比、较高萃取剂浓度和较长萃取时间有利于萃取稀土,并得到了萃取优化条件:初始水相中P_2O_5浓度10%、萃取相比V_0/V_1=3/1、萃取时间15min、P204浓度30%,在室温下萃取钇、镧、钕3种稀土,单级萃取率均可达到90%以上。     

Solid-liquid extraction of Gd(Ⅲ) and separphosphoric acid solutions using Tulsion C

Solid-liquid extraction of gadolinium was investigated from phosphoric acid medium using commercial amino phosphonic acid resin, Tulsion CH-93. The experimental conditions studied included equilibration time, acid concentration, mass of the resin, metal concentra-tion, loading and elution. The percent extraction of Gd(Ⅲ) was studied as a function of phosphoric acid (0.05-3 mol/L) using Tulsion CH-93 resin. The corresponding lgD vs. equilibrium pH plot gave straight line with a slope of 1.8. The percent extraction decreased with acid con-centration increasing, conforming ion exchange mechanism. Under observed experimental conditions the loading capacity of Tulsion CH-93 for gadolinium was 10.6 mg/g. Among several eluants screened, the quantitative elution of Gd(Ⅲ) from loaded Tulsion CH-93 was obtained with ammonium oxalate (0.15 mol/L). The extraction behavior of commonly associated metals with gadolinium was studied as a function of phosphoric acid concentration. Tulsion CH-93 resin showed selective extraction towards heavy rare earths (Lu and Yb) which could be sepa-rated from other rare earths at 3 mol/L H3PO4, similar to wet phosphoric acid (3-5 mol/L). On the other hand Gd(Ⅲ) and other rare earths were studied with chelating resin Tulsion CH-90. Light rare earths were highly extracted and these could be separated from heavy rare earths and Gd.)     

Iron recovery and rare earths enrichment from Bayan Obo tailings using Coal-Ca(O H)2-NaO H roasting followed by magnetic separation

The recovery of iron and enrichment of rare earths from Bayan Obo tailings were investigated using CoalCa(OH)_2-NaOH roasting followed by magnetic separation.The influences of roasting temperature,roasting time,coal content,milling time,Ca(OH)_2 dosage and NaOH dosage on the iron and rare earths recovery were explored.The results showed that the magnetic concentrate containing 70.01 wt.% Fe with the iron recovery of 94.34% and the tailings of magnetic separation containing 11.46 wt.%rare earth oxides(REO)with the REO recovery of 98.19% were obtained under the optimum conditions(i.e.,roasting temperature of 650°C,roasting time of 60 min,coal content of 2.0%,milling time of 5 min,and NaOH dosage of 2.0%).The Ca(OH)_2 dosage had no effect on the separation of iron and rare earths.According to the mineralogical and morphologic analysis,the iron and rare earths of Bayan Obo tailings could be utilized in subsequent ironmaking process and hydrometallurgy process.     

Study on preparation and application of novel saponification agent for organic phase of rare earths extraction

In view of the problem of ammonia-nitrogen wastewater pollution in rare earths extraction and separation, the novel saponification agent of organic phase, which is magnesium bicarbonate solution, was prepared with the natural rich and cheap dolomite as raw material through carbonation process. The behavior and purification of main impurities ions in the carbonation process as well as the application effect of the novel saponification agent in the extraction and separation was researched. The results showed that the concentration of Fe, Al, Si impurities ions was less than 5 ppm in the saponification agent through the development of effective removal technology, respectively. When the novel saponification agent was used in the extraction and separation, magnesium utilization rate was more than 95%, and rare earths extraction rate above 99.5% has achieved. Therefore, the technology could replace ammonia-water to saponify the organic phase in rare earth extraction and separation process.     

从某地铝土矿中直接提取稀土的可行性研究

对我国某地新发现的含有少量稀土元素的铝土矿，探讨了用离子交换法，采用盐溶液渗滤浸出及搅拌浸出提取稀土的可能性。根据试验结果，参考对Al2O3的X光衍射分析结论，配合以选择性酸浸法提取稀土的试验，认为该铝土矿中以吸附相存在的风化壳淋积型稀土矿比例很小，大部分为未风化的稀土独立矿物。     

Uranium and Rare Earth Recovery from Phosphate Fertilizer Industry by Solvent Extraction

Abstract

The paper presents a comprehensive review of the fundamental and applied aspects of the recovery of uranium and rare earths from phosphoric acid used for fertiliser production, by solvent extraction, with emphasis on the data from the pilot plant operated in Romania. The occurrence of uranium and rare earths in various phosphatic deposits is described and variations discussed. The radioactivity of the phosphatic rock is shown to be a cause for concern for control over pollution. History of the commercial recovery operations is decribed and the role of economic factor highlighted. The acidulation of phosphate rock, behavior of uranium and rare earths, influence of iron and effect of humic matter in the sulphuric acid process and the nitric acid process is discussed- Uranium extraction from the phosphoric acid by acidic organophosphorus esters is discussed in detail. The industrial flowsheets are described. Details are presented for the single cycle extraction process developed in Romania. Cost estimates are given which show the superiority of the single cycle process and its capability to produce uranium at a competitive price, while also producing rare earths as a by-product. Process flowsheet with stream data is also given for treatment of the solution obtained by nitric acid attack of the phosphate rock. Analysis of the uranium green cake (UF₄) and the rare earth concentrate is given.     

Dependence of Magnetic Properties of Rapidly Quenching （Nd, Pr）x（FeCoZr）94-xB6 Bonded Magnets on Rare Earths Content

By using sub-everquenching and annealing method which has a wide processing window, (Nd, Pr)x(Fe-CoZr)94-xB6(x=12, 10.5, 10, 9) bonded magnets were prepared and the effect of rare earths content on magnetic properties was investigated. Being spun at sub-ove, quenching speed the as-spun ribbons consist of amorphous phases mixed with fine crystallites. After crystallization under optimum annealing conditions and bonded with 3.25%(mass fraction) epoxy, the magnets obtained the optimum magnetic properties. The rare earths content directly determines the magnetic properties. With the reduction of rare earths content, Br increases but Hci and (BH)max decrease, x=10 is the critical value for the magnetic properties change. Below this value, Br increases slowly meanwhile Hci and (BH)max decrease strongly because alloy contains extra fractions of soft magnetic phase which are not coupled with the hard magnetic phase. This experimental result is consistont with the calculated results using the model of volume fraction of soft magnetic phase coupled completely suggested.