苯并15-冠-5接枝聚乙烯醇制备优化及其锂同位素分离效应研究  

Preparation and Characterization of Polyvinyl Alcohol Copolymer Grafted with 4'-Formoxylbenzo-15-crown-5-ether for Lithium Isotopes Separation

作　　者：李团乐 裴洪昌 袁威津 严峰[2] 李建新[1] 何本桥[1] 郭冬发[3] 崔建勇[3] 

机构地区：[1]天津工业大学材料科学与工程学院分离膜与膜过程省部共建国家重点实验室,天津300387 [2]天津工业大学环境与化学工程学院,天津300387 [3]核工业北京地质研究院分析测试研究中心,北京100029

出　　处：《高分子学报》2015年第7期792-799,共8页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51303130;21376176);长江学者和创新团队发展计划(项目号IRT13084)资助项目

摘　　要：以4-甲酰基苯并15-冠-5(FB15C5)和聚乙烯醇(PVA)为原料,通过缩醛化反应制备苯并15-冠-5接枝聚乙烯醇(PVA-g-FB15C5),采用单因素实验考察了其冠醚用量、催化剂用量及PVA浓度等对冠醚固载量的影响规律,并利用响应面分析法对合成条件进行了优化.结果表明,在冠醚用量为0.79 g、催化剂用量为0.51 g、PVA浓度为3.7×104mg/L条件下,冠醚固载量达到2.11 mmol/g.在固-液萃取锂同位素分离过程中,当萃取温度为20℃,锂盐为Li Br时,其分离因子高达1.039.此外,重同位素7Li富集于固相,轻同位素6Li富集于液相.A novel polyvinyl alcohol（ PVA） grafted 4＇-formoxylbenzo-15-crown-5-ether（ FB15C5）（ PVA-gFB15C5） for lithium isotopes separation was prepared from PVA and FB15C5 as starting materials via acetalization reaction. The effects of the reaction conditions such as catalyst content（ A）,crown ether content（ B） and PVA concentration（ c） on immobilization amount of crown ether were investigated using the response surface method. The results showed that the immobilization amount of crown ether obtained under the optimum conditions of catalyst content of 0. 79 g,crown ether content of 0. 51 g and PVA concentration of 3. 7 × 104 mg /L was 2. 11 mmol / g. Further,the single stage separation factor for lithium isotopes increased with an increase in the softness of counter anion in lithium salts during the solid-liquid extraction for lithium isotopes separation via PVA-g-FB15C5 with the immobilization amount of crown ether of 2. 11 mmol / g. Moreover,the maximum value of single stage separation factor obtained by PVA-g-FB15C5 was 1. 039 when Li Br aqueous solution was used as an extraction solution at 20 ℃. It was also found that the heavier isotope-7Li was enriched in the polymer phase during the process of solid-liquid extraction,whereas the lighter one-6Li was concentrated in the solution phase.

关 键 词：4-甲酰基苯并15-冠-5 聚乙烯醇 固-液萃取 响应面法 锂同位素分离 

分 类 号：O658[理学—分析化学] O614.111[理学—化学]