Extraction of Palladium from Acidic Chloride Media into Emulsion Liquid Membranes using LIX 984N-C^®

The extraction of palladium from hydrochloric acid solutions into emulsion liquid membranes (ELMs) using LIX 984N-C as the extractant was investigated. The influential factors and the total capacities of palladium extraction were determined by a batch method. The behavior of palladium extraction by ELMs under the operational conditions-pH of the external feed phase, surfactant and extractant concentration, internal stripping phase concentration, treat ratio and agitation speed were reported. Using LIX 984N-C, palladium was effectively extracted from the external acidic chloride feed phase into the internal receiving phase of W/O emulsions. More than 92% of palladium could be extracted at a feed pH of 2 with 3% Span 80, 9% LIX 984N-C and 7M HCl at a stirring speed of 300 rpm.

Recovery of Copper Ions from Wastewater by Hollow Fiber Supported Emulsion Liquid Membrane

Recovery of copper ions from wastewater using a hollow fiber supported emulsion liquid membrane (HFSELM) was studied with LIX984N as carrier, kerosene as diluents, and sulfuric acid solution as stripping phase. Effects of compositions of feed and emulsion liquid phase, flow rates on both sides of membrane, and hollow fiber module parameters were investigated. The stability of the emulsion liquid phase without surfactant and the effect of buffer in the feed phase on the extraction rate were also evaluated. It is found that the stability of the emulsion phase without surfactant is poor. Higher flow velocity gives shorter residence time for the emulsion liquid phase on the tube side, reducing the effect of particle coalescence on the separation process. The extraction rate increases with the increase of feed phase pH, carrier concentration, hydrogen ion concentration in the stripping phase, and ef- fective hollow fiber area. The phase ratio in the emulsion liquid phase has a negative effect on extraction rate. The flow rates on both sides have little influence on the extraction performance of the HFSELM, while buffer addition in the feed solution improves the extraction efficiency.

Rare earth extraction from wet process phosphoric acid by emulsion liquid membrane

The recovery of rare earths （RE） during the wet processing of phosphoric acid is very important, the method of emul- sion liquid membrane （ELM） with di（2-ethylhexly） phosphate （D2EHPA） as carrier has the high selectivity while cannot provide a satisfactory extraction rate. Here novel method of emulsion liquid membrane （ELM） using Aniline as carrier to extract RE from the feed solution was proposed. The method could increase the extraction rate of RE in the real sample to 93%. The effects of dif- ferent parameters such as type and concentration of carrier and surfactant, hydrochloric acid concentration, organic to internal phase volume ratio, membrane to external phase volume ratio on extraction of RE3＋ were investigated. Quantitative extraction （〉93%） of RE3＋ was observed with 6 vol.% Aniline and 4 vol.% T 154 liquid membrane at external to internal phase volume ratio of 10 for the feed solution. The proposed method of ELM using Aniline as carrier can be expected to provide a practical, efficient, and economical method for extracting RE from phosphate leach solution with high acidity in the industry of wet process phosphoric acid.

Extraction of Neodymium by Emulsion-Liquid-Membrane within Hollow-Fiber-contactor and Its Mass Transfer Properties

A non-dispersive extraction technique, using an emulsion liquid membrane within a hollow-fiber-contactor for the extraction and enrichment of Nd^3＋ from the dilute feed aqueous, was applied. The emulsion system is consisted of span80 [ sorbitian monooleate], paraffin oil, D2EHPA [ 2-（ 2-ethylhexyl- phosphonic acid）], kerosene as well as HCl solution. The extraction under various conditions such as the span80 concentrations, the flow rate of aqueous, the extraction time and HCl concentrations in receiving phase were studied. Results show that the lower the flow rates of aqueous are, the higher the extraction percentage and enrichment-fold are, and the extraction percentage increases with the increasing of HCl concentrations. When the initial Nd^3＋ concentration in feed is maintained at 1000 mg· L^-1 and the emulsion is recycled with 70 times by a counter-flow,

Extraction of rare earth ions from phosphate leach solution using emulsion liquid membrane in concentrated nitric acid medium

It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferior. Based on this question, our team modified D2EHPA to synthesize new extractants. This paper presents a comprehensive study on the extraction of rare earth ions （RE3＋） from phosphate leach solution using emulsion liquid membrane （ELM） in concentrated nitric acid medium. The ELM system is made up of （RO）2P（O）OPh-COOH as carrier, polyisocrotyl succinimide （T154） as surfactant, sulfonated kerosene as diluent, phosphoric acid （H3PO4） as stripping solution. Different chemical parameters such as type and concentration of carrier, surfactant, stripping solution, volume ratio of oil phase to internal phase, and volume ratio of emulsion ratio to external phase were analyzed. The extraction of RE^3＋ was evaluated by the yield of extraction. In addition, the demulsification process was also investigated. The proposed method of ELM using （RO）2P（O）OPh-COOH as carrier can he expected to provide an efficient, simplify operation, and facilitated method for extractine RE^3＋.

Extraction and Enrichment of Copper by Liquid Emulsion Membrane Using LIX 664N

Process intensification using liquid emulsion membranes (LEMs) for extraction of copper has been studied in this work. In LEM process the extraction and stripping processes are combined in one stage. The solubility of the solute or the chemical affinity between the solute and carrier reagent in the membrane results in the separation of the solute from the feed mixture. In this work the membrane phase comprised of LIX 664N as the extractant dissolved in kerosene and Span 80 as surfactant. The stripping phase was sulfuric acid with 180 g/l concentration and feed phase had copper concentration of 3.5 g/l. Effect of various process parameters such as batch contact time, speed of agitation, W:O ratio and treat ratio has been experimentally investigated to get better insight of the process. The maximum enrichment of copper in the internal phase obtained was 11.6 times with batch contact time of 10 minutes, agitation speed of 300 rpm and treat ratio of 6:1.

Extraction of Copper from Waste Solution Using Liquid Emulsion Membrane

The extraction of copper from acidic medium using Liquid Emulsion Membrane LEM as contactors was studied. b diketone LIX 54 as an extractant ,sesqueoleate which is nonionic surfactant with HLB value 3.7 and 0.1 M H2SO4 as stripping solution were used. The influence of initial concentration of copper in the aqueous feed phase, pH of external and internal aqueous phase, stirring speed, and concentration of extractant on the extraction rate was examined. The results obtained showed that practically all the copper content was removed from the acidic feed solution. The recovery of copper attained 96–100% and concentration ratios of about 40-fold could be achieved.

R_2PO_4H-Span80-煤油乳化液膜体系萃取Ni^(2+)的研究

研究了R2PO4H-Span80-煤油乳化液膜体系萃取含Ni2+溶液,经实验得到了最优化的萃取条件,同时研究并找出了R2PO4H类双亲分子作为载体时的最佳载体.

R_2PO_4H-Span80-煤油乳化液膜体系萃取Ni^(2+)的研究

研究R2PO4H-Span80-煤油乳化液膜体系萃取含N i2+溶液,经实验得到了最优化的萃取条件,同时研究并找出了R2PO4H类双亲分子作为载体时的最佳载体.

P204-TBP协萃体系用于乳状液膜提取铀(Ⅵ)的研究

介绍了Ｐ２０４－ＴＢＰ协萃体系用于乳状液膜法提取铀（Ⅵ）的研究。研究了在乳状液膜法中协萃载体ＴＢＰ的用量、乳状液膜制备条件、乳状液膜的膜相、膜内相和膜外相的组成对提取铀（Ⅵ）的影响。实验结果表明：（１）在硝酸铀酰体系中，膜相协萃载体ＴＢＰ占载体总量２０％—４０％时，铀（Ⅵ）的分配比是单一载体Ｐ２０４的３倍左右；在硫酸铀酰体系中，也有明显协同萃取效应。（２）当表面活性剂Ｓｐａｎ８０的体积分数为２％、膜内相Ｈ２ＳＯ４浓度为３—３．５ｍｏｌ／Ｌ时，可获得稳定的乳状液膜；膜外相ｐＨ控制在２左右，能获得满意的铀（Ⅵ）提取率；对铀（Ⅵ）含量较高的料液应该提高协萃载体浓度或适当增加乳状液与膜外相料液的体积比；料液中存在Ｆｅ３＋离子对液膜提取铀（Ⅵ）会产生不良影响，而ＳＯ２－４离子的影响并不明显。（３）Ｎａ２ＣＯ３溶液虽然也是铀（Ⅵ）的良好反萃剂，但它不能作乳状液膜法中提取铀（Ⅵ）的膜内相。膜内相的选择不仅考虑它是合适的常规反萃剂，而且要考虑膜内相与膜相的相容性。

锌冶炼过程中提取镓的技术研究及其进展

针对镓从锌冶炼过程中回收占比低的问题,总结分析了锌冶炼过程中镓回收技术研究进展.在鼓风炉炼锌(ISP)工艺中,镓主要富集在鼓风炉炉渣里,其质量分数通常在0.025%~0.031%,从鼓风炉炉渣中回收镓主要有还原蒸发法、高温氯化挥发法、硫酸浸出法、碱熔–浸出法、还原熔炼–电解法和还原熔炼–熔融造渣法等方法,但这些工艺普遍流程长,回收率低,加工成本偏高,部分工艺环境污染大,难以工业化应用.传统的湿法炼锌工艺中,大于93.5%的镓富集在浸出渣中,浸出渣处理以火法还原挥发工艺为主,在回转窑挥发浸出渣工艺中90%的镓保留在窑渣中,导致镓的回收流程长且回收率低,湿法处理浸出渣存在镓和铁分离的难题,至今未得到有效解决.氧压浸出炼锌工艺中,镓主要富集在锌粉置换渣里,锌粉置换渣采用酸性浸出和萃取工艺分离富集镓,最终制备金属镓,镓的综合回收率达到71%.通过对火法和湿法炼锌中镓回收工艺进行分析,对镓回收工艺中存在的关键问题和分离技术进行了总结,提出萃取分离、乳状液膜和树脂吸附有望成为锌冶炼过程中回收镓的绿色高效短流程关键技术.

乳状液膜法分离富集烟草提取物中的烟碱

【目的】优化并构建水包油包水(W/O/W)型乳状液膜体系,为有效分离富集烟草提取物中的高浓度烟碱及其开发利用提供参考依据。【方法】以降烟碱为模板分子,通过单因素试验对外水相pH、表面活性剂种类及用量、膜载体种类及用量、油内比、内水相HCl浓度、迁移时间及乳水比进行优化,在此基础上对外水相pH、膜载体D_2EHPA用量、表面活性剂T154用量和内水相HCl浓度开展4因素5水平的正交试验筛选,采用紫外可见分光光度法和高效液相色谱法评价乳状液膜体系对烟草提取物中烟碱的分离效能,以此确定乳状液膜体系的最佳条件。【结果】正交试验中,4个因素对乳状液膜体系的萃取率影响排序:外水相pH=表面活性剂T154用量>膜载体D_2EHPA用量>内水相HCl浓度。通过比较单因素试验和正交试验优化的乳状液膜分离体系对降烟碱的分离富集效率,确定单因素试验优化获得的乳状液膜体系条件最佳:表面活性剂为3%T154,膜载体为3%仲辛醇和5%D_2EHPA,内水相为0.5 mol/L HCl,外水相p H为13,油内比10∶8,乳水比2∶25,迁移时间2.5 min;在该条件下,乳状液膜体系对0.05 mg/mL烟碱和降烟碱的萃取率分别达85.07%和91.42%,对烟草提取物中烟碱成分的分离富集效率可达74.80%,且分离所得样品中烟碱浓度为原样的2.17倍。【结论】优化所得乳状液膜体系能快速有效地分离富集烟草提取物中的高浓度烟碱,表现出较好的应用潜力。

新型乳状液膜萃取RE(Ⅲ)动力学条件研究

稀土元素间电子层结构和物理化学性质极其相似,导致其难以分离,因此,稀土元素萃取分离一直是稀土冶金的研究热点问题。研究了以6%D2EHPA为流动载体、5%T154为表面活性剂、3.0mol/LHCl溶液为内水相、磺化煤油为膜溶剂,控制相比(Roi)为1.5制备一种新型乳状液萃取剂。通过用该乳状液萃取剂在硫酸体系下分别萃取La^(3+)、Ce^(3+)、Sm^(3+)、Eu^(3+)、Ho^(3+)和Er^(3+)6种稀土离子,确定了乳状液膜法(ELM)萃取RE(Ⅲ)的最优动力学条件。结果表明:最优动力学条件为乳化时间5min,萃取时间6min,乳水比(Rew)0.5,萃取温度25℃,外水相为稀土元素水溶液;该条件下,La^(3+)最高萃取率为99.92%,最大富集比为3.33,传质速率k=9.35×10^(-10)m/s,ELM对低浓度La^(3+)溶液表现出优异的萃取性能和富集效果。

液膜法处理对硝基苯胺废水的研究

本文研究了对硝基苯胺水溶液的乳状液膜处理过程。实际工业废水经三级液膜萃取可达到国家排放标准。对硝基苯胺盐在有机膜相的“渗漏”

液膜法从金矿贫液中除氰及回收氰化钠的小型工业化试验

本文提出了一种用乳化液膜法处理金矿含氰废水的新工艺,建立了规模为日处理量10～20m^3的一套小型工业化试验的液膜装置。研究了传质的影响因素及操作参数对除氰和回收氰化钠的影响。经运转操作证明,用该工艺流程能有效地从锌粉置换后的含氰贫液中将氰化钠浓缩回收并可重复使用,同时,使排放液中的游离氰根离子浓度低于0.5mg/L,达到国家排放标准。整个过程,氰的去除率达99％以上,氰化钠的回收率高于90％。经三个月的运转操作进行了经济估算,证明液膜法较其它方法优越。

液膜法分离富集对氨基酚

A study on separation and enrichment of p aminophenol from aqueous solution with emulsion liquid membranes has been carried out The effects of pH in internal aqueous phase, the concentration of the carrier and surfactant were examed Under the optimal operation conditions, the experimental results show that the water treated attained the drainage standard when the concentration of p aminophenol is 500mg·L -1 , after dealing with two stage liquid membrane

N503为载体的乳状液膜提取钯(Ⅱ)的研究

研究了以N ,N 二 (1 甲庚基 )乙酰胺 (N 5 0 3)为流动载体、兰 113A为表面活性剂、煤油为膜溶剂 ,EDTA做内相试剂的乳状液膜体系迁移钯的机理 ;其迁移钯的反应经紫外可见光谱证实为阴离子交换反应。在所筛选出的适宜制乳及迁移提取等最佳条件下 ,98%以上的钯迁入内相。

乳化液膜法提取苯酚的动力学研究

研究了以双丁二烯亚胺-煤油作膜相.NaOH溶液为内水相的乳化液膜提取苯酚的动力学特性,测定了膜相与内外水相组成、搅拌速度、温度对提取速率的影响,得出了提取速率规律.本文实验条件下乳化液膜提取苯酚的过程属扩散控制,其阻力主要存在于外水相.苯酚从外水相主体转移至外水相-膜界面的扩散是提取过程的速控步骤.

提溴技术研究进展与展望

近年来,我国含溴卤水资源中溴浓度日益降低,而主流的空气吹出提溴工艺存在能耗高和温度适用范围窄的缺陷,当含溴卤水浓度较低时,空气吹出法提溴经济性变差。因此以降低能耗、提高效率为目标,离子交换树脂吸附法、气态膜法、乳化液膜法、鼓气膜吸收法和超重力法等提溴方法得以广泛研究。在简要分析水蒸汽蒸馏法提溴和空气吹出法提溴技术特点的基础上,对离子交换树脂吸附法、气态膜法、液膜法、鼓气膜吸收法和超重力法等提溴技术的研究进展进行了综述,并讨论了上述各种提溴方法的优势和进一步的研究方向。

乳状液膜分离提取荷叶中3种生物碱

建立了用W/O型乳状液膜分离提取荷叶中3种生物碱——N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱的方法。通过对迁移时间、表面活性剂Span 80用量、载体D2EHPA浓度、油内比、乳水比和内水相盐酸浓度的优化,获得了高效的液膜体系,为:迁移时间2.5 min,表面活性剂Span 80的质量分数为3.0%,载体D2EHPA的浓度为0.01 mol/L,油内比为10∶6,乳水比为10∶60,内水相盐酸浓度为0.2 mol/L。在优化的实验条件下,对荷叶中3种生物碱N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱的萃取率分别达到了95.6%、100%和97.9%,相应的富集因子依次为8.73、8.50和8.04。说明该乳状液膜体系能够很好地分离提取荷叶中的N-去甲基荷叶碱、O-去甲基荷叶碱和荷叶碱。