- 學位論文
以實驗設計法進行麻瘋樹油微波轉酯化製備生質柴油之最佳化設計
The Optimization of the Microwave-assisted Transeterification of Jatropha curcas Oil to Biodiesel Fuel by Experimental Design Methodology
摘要
本研究是設計一套新型微波反應系統用來做為麻瘋樹油轉脂化製備甲基酯的實驗，甲基酯的純度96.5％以上的產品，可稱為生質柴油。利用Box–Behnken實驗設計來最適化程序變數: 甲醇/油莫耳比(X1)、催化劑(均相及異相)用量(X2)和流量或照射時間(X3) (反應時間)。以麻瘋樹油為原料，用均相NaOH及異相CaO-KOH做為催化劑，並利用回應曲面法來研究微波反應系統製備生質柴油實驗，除找出最佳條件以得到高轉化率的製程方法之外，並探討三因子之間的相互影響關係。實驗結果顯示，甲醇/油莫耳比(X1)、催化劑(均相及異相)用量(X2)和流量或照射時間(X3) (反應時間)對轉脂化及轉化率都有重要的影響，均相及異相觸媒的最佳轉化率分別為99.63%及97.60%。以回應曲面法為基礎，在微波反應系統下反應，實驗結果在均相及異相觸媒的最佳轉化率分別為 : 99.63% (X1= 10.74, X2= 1.26, X3 = 1.62)；97.08% (X1= 8.42, X2= 3.17, X3 = 67.90)，我們的研究結果證實，成功發展一個兩步驟法並輔以微波反應系統將麻瘋樹油轉脂化生產生質柴油是有效率和節省時間的方法。
並列摘要
A simple continuous process was designed for the transesterification of Jatropha curcas oil to alkyl esters using microwave-assisted method. The product with purity above 96.5% of alkyl ester is called the biodiesel fuel. The process variables such as methanol/oil molar ratio (X1), amount of catalyst (X2) and flow rate (irradiation time) (X3) were discussed and optimized through the Box–Behnken experimental design. Using response surface methodology, a series of experiments with three reaction factors at three levels were carried out to investigate the transesterification reaction in a microwave and conversion of alkyl ester from Jatropha curcas oil with the homogeneous catalyst of NaOH and the heterogeneous catalyst of KOH-CaO. The results showed that the ratio of methanol to oil, amount of catalyst and flow rate (irradiation time) have significant effects on the transesterification and conversion of alkyl ester. Based on the response surface methodology using the selected operating conditions, the optimal conversion of homogeneous catalyst and heterogeneous catalyst in the microwave-assisted system were 99.63% (X1=10.74, X2=1.26, X3 =1.62) and 97.08% (X1=8.42, X2=3.17, X3 =67.90) respectively. From the above mentioned results, response surface methodology (RSM) based on Box–Behnken model was demonstrated to predict the optimum condition for this system. Our findings confirmed the successful development of a two-step process for the transesterification reaction of Jatropha oil with microwave-assisted heating, which is effective and time-saving for alkyl ester production.