請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/58238
標題: | 油品品質電化學阻抗感測器─生質柴油與酒精汽油的應用 Electrochemical Impedimetric Oil Sensors: Applications on Biodiesel and Gasohol |
作者: | Yi Kung 龔毅 |
指導教授: | 陳力騏 |
關鍵字: | 火山灰,類固態觸媒,轉酯化反應,生質柴油,酒精汽油,混合比,含水率,電化學阻抗分析法,穿流式分析法, Volcanic ash,Quasi-heterogeneous catalyst,Transesterification,Biodiesel,Gasohol,Blending ratio,Water content,Electrochemical impedance analysis,Flow-through analysis, |
出版年 : | 2014 |
學位: | 博士 |
摘要: | 本研究利用疏水性電極對開發一油品品質阻抗感測器,其可成功地應用於生質柴油與酒精汽油之檢測。而為了獲取不同品質之生質柴油,此間提出一以表面改質之火山灰作為轉酯化反應觸媒的新型態生質柴油合成法。
Part 1. 表面改質火山灰應用於生質柴油之合成 本研究將火山灰(100 ∼ 400 μm)與鹼進行表面改質製成鹼性類固態觸媒,並應用於生質柴油的合成。由日本鹿兒島縣櫻島火山所採集的火山灰其本質為含金屬氧化物之二氧化矽晶體(表面元素分析:氧佔61 %;矽佔20 %;其餘含量為金屬離子),為高表面積/體積比之多孔性廢棄物。在相同的鹼使用量下,此觸媒不需經鹼預溶於醇類之程序即可進行反應,且與習用方法有相似的轉酯率。與同量未經預溶的鹼觸媒反應相比可提升約15 %之轉酯率。由於火山灰有高反應表面積、高密度的性質,氫氧化鈉佔三酸甘油酯重量比可控制在0.2 %之低鹼使用量,大幅地降低生產成本與環境負擔。 Part 2. 電化學阻抗分析法應用於生質柴油混合比之檢測 本研究中開發了一兼具操作流程簡便與檢測時程快速(< 10 s)的生質柴油品質分析感測器,其檢測原理建立於電化學阻抗分析頻譜之上,並搭配自製之拋棄式網印碳電極檢測槽(電極係數 = 0.04 cm^-1)進行分析。在低頻區域(< 1 Hz)中,生質柴油混合物之阻抗響應可有效地檢測出其混合比例(B0 ∼ B100),並有優異的解析度與再現性(CV < 3 %,實驗8重複;r^2 > 0.98)。 Part 3. 電化學阻抗分析法應用於酒精汽油混合比與含水率之檢測 酒精汽油之乙醇含量可經由以疏水性玻璃碳電極(電極係數 = 0.3 cm^-1)組裝之自製穿流式電化學阻抗檢測槽進行分析,搭配上樣品除水前處理機制之設計,藉由於320 Hz之阻抗響應,即可在1秒內獲知樣品混合比、含水率等重要品質參數。且本檢測系統具良好的溫度耐受性(20 ∼ 40 oC)與再現性(相對標準差 < 2 %,實驗10重複)。 本研究以低電極係數�電極對建構之阻抗感測器於數秒內即可有效地進行生質燃料品質之檢測,未來可引以為基石進一步應用於他種疏水性物質之檢測、分析。 Impedimetric sensors were developed for oil quality with a pair of hydrophobic electrodes, and their applications on assaying biodiesel and gasohol quality were demonstrated. To obtain biodiesel with different quality, a novel biodiesel synthesis method was proposed using surface-modified volcanic ash as the catalyst for the transesterification reaction. Part 1. Volcanic ash as a quasi-heterogeneous catalyst for biodiesel synthesis Biodiesel is generally the methyl esters of fatty acids synthesized by transesterification of triglycerides; the reaction can be catalyzed by homo- or heterogeneous catalysts. The proposed method alkalinized the porous surface of volcanic ash (100 ~ 400 μm) with caustic soda, and used it as a quasi-heterogeneous catalyst with the performance comparable with the conventional base-catalyzed reaction using caustic soda pre-dissolved in methanol. Due to the high surface to volume ratio and high density of the porous catalyst, the usage of caustic soda can be reduced to 0.2 % (wt/wt) of the starting material, triglycerides. The result revealed the industrial potential of the unused natural resource for biofuel production. The biodiesel synthesized thereof was used afterwards. Part 2. Impedimetric estimation of the blending ratio of biodiesel with a carbon paste electrode pair A rapid (< 10 s) and simple impedimetric sensor for estimating the biodiesel quality had been developed with an electrochemical chamber consisted of two hydrophobic electrode pair (two identical screen printed carbon paste electrodes). The two electrodes were faced together with a low cell constant (0.0408 cm^-1) to lower the impedance for a more precise measurement. In low frequency region (< 1 Hz), the impedance response (CV < 3%, n=8) was useful to estimate the blending ratio of biodiesel (r^2 > 0.98) with good resolution, reproducibility and thermal stability which is important for the quality control and regulation of the eco-friendly fuel. Part 3. Impedimetric sensing of the ethanol and water contents in gasohol with a flow-through carbon electrode pair A flow-analytical system with a flow-through hydrophobic electrode pair (two identical glassy carbon electrodes, cell constant = 0.3 cm^-1) was developed. Based on the impedimetric signal at 320 Hz, the ethanol contents in gasohol can be measured in less than 1 s with sufficient temperature tolerance (20 to 40 oC) and reproducibility (relative standard deviation < 2 % for ten tests). The water content can also be estimated by comparing the impedance data obtained with and without desiccation. The two-electrodes / low cell constant impedimetric sensors were proven to be useful in estimating bio-fuel quality in seconds, other analytical applications on hydrophobic material are highly expected. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/58238 |
全文授權: | 有償授權 |
顯示於系所單位: | 生物機電工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-103-1.pdf 目前未授權公開取用 | 2.42 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。