摘要
研究了以OP-7[壬基酚聚氧乙烯(7)醚]和OP-4[壬基酚聚氧乙烯(4)醚]为非离子表面活性剂、苯甲醇为助表面活性剂所形成的W/O型微乳液体系(OP-7+OP-4)/苯甲醇/D2EHPA/煤油/盐酸在不同混合表面活性剂配比、盐酸浓度、温度、NaCl浓度等条件下对盐酸的增溶性能;将微乳液作为液膜用于对稀土钕的萃取时,采用了新的膜萃取过程即微乳液/中空纤维膜接触器萃取。结果表明,微乳液对盐酸的增溶量随混合表面活性剂的亲水亲油平衡值(HLB值)以及盐酸浓度的增大而增大,随温度的升高、NaCl浓度的增大而减小。当以逆流方式萃取时,微乳液内相盐酸浓度越大,萃取率越高,但内相富集倍数减小;当微乳液流量为6mL·min^(-1)、料液初始浓度为200mg·L^(-1)、有效萃取时间为6min时,Nd^(3+)的萃取率达96.3%,微乳液内相浓度富集倍数为21.2,有效萃取时间超过6min后,萃取率基本不变,表明该非离子型微乳液对钕Nd^(3+)具有很好的萃取和富集功能,所采用的新膜萃取过程同时具有膜萃取过程的热力学稳定性和液膜分离过程非平衡性的优点。
The nonionic microemulsion （ME） system was prepared , which was composed of OP-7 （polyoxyethylene （7） nonylphenol） and OP-4 （polyoxyethylene （4） nonylphenol） as nonionic surfactants, benzylacohol as assistant surfactant, D2EHPA （2-（2-ethylhexyl） phosphonic acid） as extractant, kerosene as oil-phase medium and HCI solution as inner receiving phase. The effect of the parameters, such as the mass ratio of OP-7 to OP-4, the HCI concentration, the system temperature and the NaCI concentration in the extracted solution, on the solubilization of HCI solution in the prepared ME system were investigated. The results show that the content of HCI solution in the microemulsion increases with the increase of the HLB value（Hydrophile-Lipophile balance value） of the mixed surfactants （i.e. OP-7 and OP-4） and the hydrochloric acid concentration. On the contrary, the increase of the temperature or NaCI concentration leads to a decrease of the content of HCI solution in the microemulsion. While the prepared ME system was used as the liquid membrane in a hollow-fiber contactor to extract the Nd^3＋ from its solution, the extracted Nd^3＋ percentage reaches 96.3% and the Nd^3＋ concentration in receiving phase is 21.2 times of its initial feed concentration （i.e. 200 mg·L^-1）. It shows that the proposed microemulsion extraction process has good performances of extraction and enrichment, and it also has both the advantages of the thermodynamic stability of solvent extraction and the non-equilibrium property of the separation using emulsion-liquid membrane.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2007年第3期375-380,共6页
Journal of Chemical Engineering of Chinese Universities
关键词
非离子型微乳液
增溶
中空纤维膜接触器
萃取
钕
nonionic-microemulsion
solubilization
hollow-fiber contactor
extraction
neodymium
