聚羥基丁酸硫酸甲醇化反應動力學研究

Kinetic Study of Polyhydroxybutyrate by Acidic Methanollysis

林坤榮(Kun-Jung Lin)

指導教授 ： 吳和生

元智大學/工程學院/化學工程與材料科學學系/碩士(2004年)

摘要

中文摘要
聚羥基烷酸（PHAs）是由微生物發酵生產出來的塑膠，為細菌細胞內的酯類堆積物，稱為生物可分解性塑膠，PHAs具有許多之優點，並符合「環保材料」的要求。本研究在探討聚羥基丁酸 Poly(3-Hydroxybutyrate) (PHB))，經硫酸甲醇化﹙acidic methanollysis﹚處理之動力學研究，目前使用烘箱做為酸甲醇化之容器，本研究設計一反應器做為試驗設備，另外設計一玻璃試管(glass tube)附螺帽之加熱器，做為酸甲醇化解離之試驗用，所以設計之反應器為此次試驗成敗之關鍵。
其次降解過程中，溫度對降解速率的變化，即在固定酸濃度，不同溫度對PHB的含量變化，在固定溫度下，不同酸濃度對PHB的降解狀況。根據試驗結果可找尋建立快速分析方法，以幫助鑑定發酵所產出之種類和成份，回饋做為修改發酵程序之資訊。
PHB在酸性條件下進行酸甲醇化，解離成HB單體，目前使用濃硫酸做為觸媒，酸為觸媒，鹽酸也為一強酸，鹽酸也可做為酸觸媒。
PHB經酸甲醇降解預反應形成單體，以氯仿萃取，發現此單體脂類，可同時存在於油水兩相之間，使得分析數據產生誤差。以氯仿萃取PHB酯化降解溶液，加入NaCl水溶液試驗，發現此單體可由水相轉移至油相，使回收率提高達到98％。

關鍵字

聚羥基丁酸 ； 酸甲醇化

並列摘要

Abstract
Polyhydroxyalkanoates(PHAs) is the plastic which is produced by the way of fermentation of bacterium. However, it is the intracellular product can be decomposed by bacterium. Having a lot of advantages and up to requires of green technology. The major purpose of this research is to investigate the kinetics of the PHAs via acidic methanolysis. Using oven as the vessel to design a reactor used for acidic methanolysis and the heater of glass tube to be the equipment for the decomposition. So, the design of the reactor is the important sticking point.
In the procedure of the decomposition, this research discuss about the effect of temperature to the reaction rate. The experiment methods are in different temperature condition cause different content of PHA in a certain acid concentration and in different acid concentration condition cause different decompose result in a certain temperature. According to the result, it can help us establish the method to analyze in order to ensure the component of the product made via fermentation.
In the acid condition, due to the procedure of acidic methanolysis, PHB will be decomposed to monomer as HB. In present, the sulphuric acid will be used as catalyst. And then, chloroform will be used to extract the monomers that can exist in both organic phase and aqueous phase to cause the deviation of consequence. But adding some NaCl in aqueous phase can make the monomers transfer from aqueous to organic phase and the conversion will be up to 98%.

並列關鍵字

Polyhydroxyalkanoates

參考文獻

1. Anderson, A. J.,and E. A. Dawes, Occurrence metabolism metabolic role and industrial uses of bacterial polyhydroxyalkanoates, Microbiol. Rev., 54, 450-472, 1990.

2. Asrar, J., and J.C. Hill, Biosynthetic Processes for Linear Polymer. J. Appl. Polym. Sci., 83,457-483, 2002.

4. Braunegg, G., B. Sonnleitner, and R. M. Lafferty, A rapid gas chromatographic method for the determination of poly-β-hydroxybutyrate acid in microbial biomass, Eur J Appl. Microbio Biotechnol, 6, 29-37, 1978.

5. Byrom, D., polymer synthesis by microorganisms technology and economics, Trends Biotech., 5, 246-250, 1987.

8. Doi, Y., Microbial polyester, VCH, New York, 1-50, 1990.