(1. 東北大學(xué) 冶金資源與環(huán)境工程研究所，沈陽 110004；2. 北京有色金屬研究總院 稀土材料國家工程研究中心，北京 100088；3. 有研稀土新材料股份有限公司，北京100088)
摘 要: 采用恒摩爾法、斜率法以及飽和容量法研究從硫酸介質(zhì)中用P204(D2EHPA，用(HA)2表示)與P507(HEHEHP，用(HL)2表示)協(xié)同萃取Nd3+或Sm3+的性能與機(jī)理，并測(cè)定協(xié)萃反應(yīng)的熱力學(xué)平衡常數(shù)Ks.e，求得反應(yīng)的焓變和熵變。結(jié)果表明，萃取反應(yīng)呈現(xiàn)正協(xié)同效應(yīng)，且協(xié)萃過程為放熱反應(yīng)，協(xié)萃配合物組成分別為Nd∙(HA2)2∙HL2和Sm∙(HA2)2∙HL2。因此，P204與P507混合使用可以改善硫酸介質(zhì)下稀土的萃取分離效果。
關(guān)鍵字: P204；P507；硫酸介質(zhì)；協(xié)同萃取；Sm3+；Nd3+
（1. Institute of Metallurgical Resources and Environmental Engineering, Northeastern University, Shenyang 110004, China;2. National Engineering Research Center for Rare Earth Materials, General Research Institute for Nonferrous Metals, Beijing 100088, China;3. GRIREM Advanced Material Co., Ltd, Beijing 100088, China）
Abstract:The mechanism and characteristics about synergistic extraction of Nd3+ and Sm3+ by D2EHPA and HEHEHP from sulfuric acid medium were studied through the methods of slope, constant molecule and saturation extraction. The extraction equilibrium constants, enthalpy change and entropy change of the reaction were also calculated. The results show that the compositions of the extracted compound are identified as Nd∙(HA2)2∙HL2 and Sm∙ (HA2)2∙HL2, the synergistic extractive effects are found, the extraction is an exothermic process. Consequently, the extraction and separation effect for rare earth can be improved with synergistic mixture of D2EHPA and HEHEHP.
Key words: D2EHPA; HEHEHP; sulfuric acid; synergistic extraction; Sm3+; Nd3+
