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YOSHIKAZU MIYAKE YOSHINARI BABA 《Mineral Processing and Extractive Metallurgy Review》2013,34(1-5):351-380
Abstract The mechanism and kinetics of metal extraction with several extractants, including chelating agents, acidic organophosphorous extractant and neutral extractants are discussed in this paper. Firstly the extraction rate of metal ion for the general extraction system is formulated by solving the diffusional equation with chemical reaction, in which the interfacial reaction is considered by the boundary conditions. The overall rate expressions of the complex formation with chelating agents are obtained both in aqueous phase and at the interface. The general formula of the extraction rate is simplified by considering the rate-determining steps. Next, the extraction rate of metal ion with chelating agents and acidic organophosphorous extractants is discussed. For the chelating agents, the most important properly to determine the locus of complex formation is the distribution constant between the organic and aqueous phases. The contribution of the interfacial reaction to the extraction rate increases with the increase in the distribution constant of chelating agents. The extraction rate of many metal ions with acidic organophosphorous extractant are determined by the diffusion process of final complex in the organic phase. Finally, the extraction rate of palladium ion with some neutral extractants is also discussed. The extraction rate is determined by the complex reaction in the aqueous phase and at the interface. The contribution of the interfacial reaction increases with the distribution constant of extractants. 相似文献
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HDEHP萃取稀土过程的溶剂效应 总被引:1,自引:1,他引:0
考察了在不同溶剂中HDEHP对镨、钕、钐、镝、钬、镱等的萃取,计算得到萃取表观平衡常数Kex、热力学平衡常数KΘex和萃合物的溶解度参数δc,建立了lgKex与溶剂极性参数ET(30)、α间的经验方程。发现溶剂性质不会影响萃取机理,但使HDEHP二聚体间的作用程度不同,而且显著影响萃取平衡关系。稀土离子萃合物的溶解度参数δc基本相同,萃合物的空间构型相同。 相似文献
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JAN SZYMANOWSKI 《Mineral Processing and Extractive Metallurgy Review》2013,34(3-4):389-418
Abstract Extractants and processes used and proposed for recovery of arsenic, antimony and bismuth from copper electrolytes are presented and discussed. The use of the following extractants is duscussed: tributyl phosphate, partial esters of phosphoric acid (mono(2-ehtylhexyl)phosphoric acid, bis(2-ethylhexyl)phosphoric acid and mono(isooctadecyl) phosphoric acid, - DS 5834), esters of alkylphosphonic acids, trialkylphosphine oxide, CYANEX® 923 extractant, hydroxamic acids, LIX 1104, alcohols (2-ethyIhexanol and others), hydrophobic diols and alkylpolyphenols. The chemistry and processes are presented and discussed. 相似文献
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用溶剂萃取法从含钒浸出液中直接沉淀钒 总被引:1,自引:0,他引:1
传统的从钒渣、石煤中提取钒的工艺都采用酸性铵盐沉淀钒,废水量大,能耗高,且V2O5纯度不高。采用溶剂萃取法,在反萃取过程中实现油、水、沉淀物三相共存,直接分离得钒酸铵沉淀;以N1923+仲辛醇+煤油为萃取剂,碳酸钠为反萃取剂,在萃取4min、反萃取10~15min最佳条件下,钒单次萃取率达95%以上,单次反萃取率达99%以上,得到的五氧化二钒产品质量达到GB3283—1987冶金99级标准。 相似文献
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对某石煤矿采用直接酸浸和焙烧酸浸处理,并考察不同浸出过程中氟化物加入的影响。结果表明,该石煤适宜采用含氟化物作用的直接酸浸-萃取工艺,钒浸出率可达92.39%,预处理钒损失率为1.12%,每吨V2O5的CaO耗量为6.38t,钒萃取过程正常且三级萃取率达到98.05%。不同浸出工艺及是否加入氟化物对钒萃取过程有较大的影响:无氟化物加入的直接酸浸使石煤原矿中的有机物引入酸浸液,形成界面膜而导致乳化现象产生;空白焙烧可消除有机物的影响,但由于酸浸溶液中的杂质元素含量显著增加而可能导致乳化现象;氟在溶液中以[AlF5]2-和[SiF6]2-形式存在,可阻止含硅胶体和细微颗粒以及界面膜的生成,有利于萃取正常进行,但当溶液中杂质元素含量过高时,仍可能产生乳化。 相似文献
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溶剂萃取法在钨湿法冶金中的应用 总被引:7,自引:0,他引:7
概述了溶剂萃取技术在钨冶金方面的应用。主要介绍了钨酸钠溶液的萃取转型、碱性条件下钨酸钠溶液直接萃取和萃取法分离钨、钼工艺研究进展。认为今后钨的溶剂萃取技术研究方向应是自动化、智能化,缩短工艺流程,寻求新型高效萃取剂和清洁生产工艺。 相似文献
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采用MIBK作为萃取剂,在盐酸体系下,对含铪合金渣中的铪进行萃取分离试验,主要考察合金渣中含量较高的锆、钛、铬和铪在萃前液不同氢离子浓度、NH4SCN浓度、有机相HSCN浓度及相比下的分离性能。结果表明,铪和锆钛分离难度较大、和铬分离较易,铪的最优分离条件为:萃前液氢离子浓度0.96mol/L、萃前液NH4SCN浓度2.56mol/L、有机相HSCN浓度2.73 mol/L、相比1。在最优条件下,铪和锆的相对分离系数为6.63,铪的分配比为1.79,对于锆含量较低的合金渣,可以有效提升锆铪分离效率,钛最好于萃取分离前进行分离。 相似文献
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概述了溶剂萃取在钨冶金方面的研究进展.分别从三个方面介绍了酸性条件下钨酸钠溶液的萃取转型、碱性条件下钨酸钠溶液直接萃取和钨酸钠溶液的萃取除钼工艺进展情况. 相似文献
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试验研究了苯甲酸钠、草酸钠、柠檬酸钠和酒石酸钠四种中低分子量的有机物对铝酸钠溶液(CNa2O=150 g/L,αk =1.45)粘度的影响.研究结果表明,随着有机物浓度从0升高到0.7 g/L,铝酸钠溶液的粘度逐渐降低,主要因为有机阴离子的加入抑制Al(OH)4-向聚合铝酸根离子的转变,降低了溶液的内摩擦力,从而降低了... 相似文献
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