碳酸钠皂化P204微乳液体系萃取L-茶氨酸的研究_化学专业.doc

摘  要:茶氨酸是茶叶中的一种特有的氨基酸，在医药、食品等领域具有广泛的用途。本文综述了目前茶氨酸的应用现状及萃取方法，对微乳液膜萃取过程的研究现状和意义进行了阐述；建立了微乳液膜萃取茶氨酸的新方法：研究了Na2CO3皂化HA/煤油微乳体系萃取茶氨酸的机理和工艺，考察了外水相PH值、P204浓度、乳水比、茶氨酸的初始浓度等对萃取效率的影响。结果表明，该微乳液萃取茶氨酸的最佳工艺条件为：油相中HA的浓度0.8mol/L、Na2CO3浓度3mol/L、茶氨酸浓度300mg/L、乳水比1:4、外水相PH值为3。该微乳液具有稳定性好、无明显溶胀和泄漏、萃取效率高、可自动破乳且油相可重复使用等优点。　

关键词：微乳液；二一（2-乙基己基）磷酸酯；P204/煤油；萃取；茶氨酸

ABSTRACT:Theanine is a peculiar amino acid in the tea.It possesses broad prospect in medicament,food industry and so on.In this paper,we summarized extraction method and the application situation of theanine,expond the recent research and significance of the extraction process.A new of extracting theanine by BLM was established in this paper,The mechanism and technique of extracting theanine were studied in HA/kerosene/Na2CO3 microemulsion system.The effect factors onextracting theanine from aqueous phase,including the pH value of theexternal phase;the concentration of P204;the volume ratio of microemulsion to external aqueous phase;theanine initial concentration were investigated.The results showed that the HA concent ration in the oil phase was 0.8mol/L,the concent ration of Na2CO3 was 3mol/L theanine initial concentration was 300mg/L;the volume ratio of microemulsion to external aqueous phase was 1:4,the pH value of the external aqueous phase was 3.0.The microemulsion system exhibited several advantages including good stability,low leakage and swelling,high efficiency of extraction,easy demulsification, and recoverable oil phase.

Keywords:microemulsion;di-2-ethylhexyl phosphoric acid(HA);di(2-ethylhexyl)  phosphoric acid/kerosene;extraction;Theanine