共查询到19条相似文献,搜索用时 62 毫秒
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传统的稀土元素分离提取工艺常采用单一的酸性磷酸酯类萃取剂,如使用常见的P507、P204等萃取剂来萃取稀土元素,需要先进行皂化预处理,皂化反应会产生污染性、刺激性严重的浓氨水,并产生氨氮废水及其他废水,采用这种方法会对环境造成严重污染.本实验采用P507-N235双溶剂萃取体系,以稀土铈、镨为主要萃取元素,研究对萃取稀... 相似文献
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本研究的目的是提供一种以碳酸稀土为皂化剂的稀土皂化P507-煤油有机相的制备方法。为此,系统考察了多种因素,例如,碳酸稀土用量、杂质离子硫酸根浓度、游离稀土离子浓度、相比和接触时间等因素,对稀土萃取率、分相性能和稀土负载浓度的影响。结果表明:当P507-煤油有机相与含游离稀土浓度在1 mmol/L以上的水相接触混合时,P507-煤油有机相的皂化可以快速地与加入的固体碳酸稀土反应,形成稀土皂化有机相。其皂化反应可以在几分钟之内完成,比水相中不含游离稀土离子时要快很多,这是因为受动力学条件限制的直接皂化反应已经变成了两个分立的反应:P507-煤油有机相与游离稀土离子的皂化反应以及该皂化反应析出的质子与碳酸稀土的溶解反应。基于这一特征,把P507-煤油有机相的稀土皂化设计成了多级逆流萃取皂化过程,该过程可以连续产出合格有机相并使水相在体系中保持循环。分液漏斗模拟结果证明了多级逆流皂化的可行性,确定了最佳的萃取相比为1∶1,皂化有机相的稀土负载浓度在0.12 mol/L以上。 相似文献
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用草酸溶液从负载钕的P507中直接反萃取沉淀钕 总被引:1,自引:0,他引:1
介绍了在自制的三相反萃取槽中用草酸溶液从负载钕的P507有机相中直接反萃取沉淀钕的半工业试验结果。试验结果表明,用0.3~0.5mol/L的草酸溶液从含钕0.0533和0.11135mol/L的有机相中直接反萃取沉淀钕,控制沉淀母液中草酸浓度0.2mol/L,返回使用80%的沉淀母液,在接触时间10~40min范围内,获得的Nd2O3的纯度≥99.88%。产品粒度D50在3.76~4.27μm之间,氯质量分数0.01%,非稀土杂质的质量分数符合99.9%Nd2O3产品质量要求。 相似文献
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P507萃取Pd(Ⅱ)机理研究 总被引:1,自引:0,他引:1
本文研究了2-乙基己基膦酸单2-乙基己基酯(简称P507,记作HL)从硝酸介质中萃取钯的机理。考察影响钯萃取的因素,应用斜率法、等摩尔系列法和饱和法确定萃合物组成为PdL_2;通过紫外光谱研究证实,P507萃取钯的机理属于酸性络合反应,其萃取方程式为: 相似文献
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P507萃取分离钴镍试验研究 总被引:3,自引:0,他引:3
此文推导了动力机器基础单自由度和双自由度计算模型在白噪声激励下的动力响应,并运用于钢球磨煤机基础的动力响应计算中,得钢球磨煤机基础振幅的计算公式。 相似文献
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本文研究了氯卤体系中P507萃取分离Co,Ni的基本性质,平衡水相PH值,氯离子浓度、料液酸度对分离系数βCe/Ni的影响及萃取反应的速度。对氯盐介质中Co,Ni混合料液利用P507萃取分离的工艺进行了初步探索。 相似文献
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P507和5709萃取镍钴的分配模型 总被引:1,自引:0,他引:1
本文根据萃取平衡实验及其数据的计算处理,建立了 P_(507)和5709萃取镍、钴的分配模型,其结果比以往的研究更精硬、更切合实际。 相似文献
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P507 solvent extraction is the main method to separate and purify the rare earth products.The emulsification may be caused by the impurities in process of extracting rare earths,and these result in huge economic loss and decrease the quality of rare earth products.In recent researches,the extractant was prone to emulsification,and aluminum content of rare earth products also increased,while aluminum concentration of feed was higher.Pointing to this problem,the structural change of saponification P507 extracting aluminum and lanthanum was investigated by infrared spectroscopy,and the results showed that Al ions exchanged with H of P-O-H to become P-O-Al.Because aluminum held the characteristic of hydrophilic after extracted in the form of hydroxyl polymer ions and this provided conditions for the formation of micro emulsion.The organic phase and aqueous phase were investigated by polarizing microscope after aluminum was extracted.The results showed that the organic phase was clear when the extraction capacity of Al was less than 5 g/L.If the extraction capacity of Al exceeded 5 g/L,it formed W/O of ME(micro emulsion),leading to form emulsion of the organic phase.When Al concentration of feed was less than 1 g/L,the aqueous phase would form O/W of ME.If aluminum was extracted by saponification P507 firstly,then the the organic phase loading aluminum extracted rare earth continually,the organic and aqueous phase formed emulsification easily. 相似文献
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Emulsification troubled normal extraction process of rare earths due to the existence of non-rare earth impurities,especially Si,Al and Fe.Against this background,the effect of emulsification caused by Si,Al and Fe on the La extraction with saponification P507(2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester) in chloride medium was systematically investigated.A series of experiments were carried out to study the relationship of the extraction capacity of La and the concentration of impurities.ZPM-203 polarizing microscope was applied to investigate the morphology of emulsification,and the cation exchange extraction mechanism of Fe and Al as well as La was clarified by IR spectra.The results showed that a low concentration of Si in organic phase would aggravate the emulsification with Al,and the formation of ME(micro emulsion) and club-shaped polymer would result in emulsification in the extraction of mixtures of Si and Al,single Fe,respectively.Furthermore,the accumulation of impurity such as Si,Al and Fe in the organic phase would severely reduce the extraction capacity of La simultaneously. 相似文献
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对P507-N235双溶剂无皂化萃取体系的直接沉淀工艺进行研究,将传统先反萃后沉淀工艺合二为一,从酸度、流比、草酸用量及搅拌时间等方面,考察盐酸-草酸水溶液作为P507-N235-磺化煤油体系沉淀剂直接沉淀的效果.实验以稀土钕直收率来表征实验效果的差异性.研究结果表明:通过加入盐酸调节酸度并控制一定的流比、草酸用量和搅拌时间,可大大提高沉淀的效果.最优草酸沉淀条件为:酸度0.40 mol/L、流比1:1、草酸理论用量的120 %,搅拌时间5 min,其单级钕直收率可达97 %以上.反萃后有机相结构未发生改变,萃取能力可达到新有机相的90 %. 相似文献
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研究了P507-N235混合萃取剂分离石煤酸浸液中钒与铁的工艺,考察了N235/P507浓度、萃原液pH、萃取时间、相比(A/O)对钒、铁萃取率及钒铁分离效果的影响。结果表明,采用0.4 mol/L P507,0.8mol/L N235为萃取剂,磺化煤油为稀释剂,pH=1.7,萃取时间5min,A/O=5/1,经4级萃取,钒萃取率可达98.36%,而铁萃取率仅为5.78%。相对现有的P204、P507单一体系,P507-N235体系具有更好的萃取能力及钒铁分离性能。 相似文献
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P507-N235复合有机相能很好的萃取分离稀土元素.为有效利用P507-N235复合有机相中的余酸,对载酸有机相分解稀土的试验进行了研究.结果表明,分解碳酸钕时,较优的工艺参数为料浆浓度72.5 g/L、浸出时间30 min、相比VO:VA=1:1(有机相与水相的体积比, 下同),在此条件下,30%P507+25%N235+45%煤油体系对Nd的萃取容量为20.16 g/L(按REO计,下同),有机相中余酸利用率为52.6%,且体系分相效果较好;分解氢氧化钕时,较优的工艺参数为料浆浓度73.3 g/L、浸出时间50 min、相比VO:VA=1:1,此时Nd的萃取容量可达21.6 g/L,有机相中余酸利用率为53.7%.实验证明了此方案的可行性,有机相中的残酸利用效果较好,可以实现载酸有机相的循环使用. 相似文献
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改进的P507在H_2SO_4体系中对锆铪的静态吸附实验 总被引:2,自引:2,他引:2
对P507萃淋树脂合成条件进行了改进,并用此合成的P507树脂在H2SO4体系中进行锆铪吸附分离性能的研究。研究了在不同温度与不同酸度下P507树脂对锆铪吸附性能,并求出了分离系数;研究了最佳吸附平衡时间,Hf的不同百分含量时的分离系数以及锆铪洗脱条件。 相似文献