以離子液體水解纖維素之研究

A Study of Cellulose Hydrolysis in an Ionic Liquid

陳雯苓(Wen-Ling Chen)

指導教授 ： 洪錫勳 ； 吳俊毅 ； 梁明在

義守大學/理工學院/化學工程學系暨生物技術與化學工程研究所/碩士(2015年)

https://doi.org/10.6343/ISU.2015.00144

摘要

纖維素生物質通常使用物理或化學方式轉化成醣類和有價值的化學品，但酸水解會產生許多廢酸，對環境影響較大且難以回收再利用。近年來，由於離子液體易於回收再利用且對環境汙染較小，因此離子液體廣泛應用於纖維素水解。
本研究以[Bmim]Cl離子液體作為溶劑，探討不同的操作因子，對纖維素水解反應之影響。後續則將巨王草進行預處理後，於最佳的水解條件下進行水解反應，探討預處理方式對於水解反應之影響。研究結果顯示，在100 ℃下纖維素於離子液體中溶解十二小時，有助於提升葡萄糖產率，再藉由動力學探討得知最佳溶解溫度為140 ℃~160 ℃。不同的硫酸濃度對於纖維素水解反應影響較不顯著，但反應溫度明顯影響總還原糖產率、葡萄糖產率以及產率達最大值之時間。最佳水解條件以反應溫度140 ℃，濃度為4.5×10-4 mmol硫酸，進行纖維素水解反應，得到總還原糖產率之最大值為71.89 %且葡萄糖產率最大值為25.41 %；於相同條件下，進行巨王草水解反應，發現加入過氧化氫之預處理，可以提升總還原糖之生成速率。

關鍵字

纖維素 ； 離子液體 ； 葡萄糖 ； 還原糖

並列摘要

Conversion of cellulosic biomass can directly into valuable biofuels and chemicals. However, acid hydrolysis produced much waste acid, the environmental influence is large and difficult to recycle. In recent years, ionic liquids was easy to recycle and less environmental pollution, and therefore ionic liquid widely used in cellulose hydrolysis.
In this study, several operation factors of the cellulose hydrolysis to reducing sugars is investigated in which the ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) is used as solvent with cellulose as raw material. The optimized cellulose hydrolysis condition was used to the pretreated Giant King Grass, to investigate the effects of pretreatment methods for hydrolysis reaction. The yield of hydrolysed glucose by dissolving cellulose for 12 h in ionic liquid at 100 °C is improved. Kinetics analysis of hydrolysis mechanism shows that the best dissolution temperature is from 140 ℃ ~ 160 ℃. It is not obvious to use different catalytic concentrations of sulfuric acid for cellulose hydrolysis reaction, but the effect of reaction temperature is obvious on reducing sugar yield, glucose yield and the peak time of maximum yield. Optimal conditions with hydrolysis reaction temperature 140 ℃ and the concentration of 4.5×10-4 mmol sulfuric acid were carried out to obtain the maximum yield of total reducing sugars and glucose of 71.89 % and 25.41 % respectively. Under the same operating conditions, it is found that the addition of hydrogen peroxide for pretreatment of the Giant King Grass can effectively enhance the generation rate of total reducing sugars.

並列關鍵字

Cellulose ； Ionic liquids ； Glucose ； Reducing sugar

參考文獻

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