【摘要】：隨著化石能源的逐漸枯竭和環(huán)境污染的日益嚴重,生物柴油的研究逐漸成為熱點。傳統(tǒng)間歇反應制備生物柴油的過程生產強度遠小于連續(xù)生產過程,且由于原料油脂與甲醇互溶性差,反應速率低、傳質效果差等造成生產能耗過大。同時酸堿催化劑的處理需要大量水洗,難以回收。微管反應器比表面積大、傳熱傳質性能好,可以保證物料分布均勻,維持反應體系溫度恒定,在改善多相反應傳質、強化反應過程以及提高安全性等方面有很好的工業(yè)應用前景。而離子液體具有綠色無污染、與生物柴油易分離、可循環(huán)使用等優(yōu)點,被認為是21世紀最有希望的綠色溶劑和催化劑之一,在催化酯交換制備生物柴油領域具有廣闊的應用前景。因此,進行微管內離子液體催化制備生物柴油的探索研究,將具有重要意義。本文首先對原料大豆油的理化性質進行分析,確定了原料中各成分的組成比例,核算出大豆油的相對分子量為870.31g·mol-1,基于氣相色譜法確定了以十一酸甲酯為內標物的生物柴油定量分析方法；然后分別以傳統(tǒng)酸堿催化劑和固體催化劑進行了間歇法催化制備生物柴油的反應研究,結果表明在合適的條件下,KOH催化產率可達到90.67%。然后采用PTFE材質微管作微反應器,T型微混合器用于大豆油和甲醇的混合,分別考察停留時間、反應溫度、醇油摩爾比、催化劑用量四個單因素對酯交換反應的影響,并通過響應面法設計試驗,利用Design-Expert對實驗結果進行分析,考察各因素之間對生物柴油收率影響的交互作用。并確定了微管反應器內KOH催化酯交換的最優(yōu)反應工藝：停留時間100s,反應溫度58℃,醇油摩爾比9.70,催化劑用量1.57%,在此條件下轉化率可達94.21%�；谝陨祥g歇反應器和微管反應器中的最佳轉化率進行工業(yè)放大設計計算,發(fā)現微管反應器在兩種排布方式下,都可大大減小反應器總體積,實現高效快速生產,避免放大效應。最后本文進行了離子液體催化酯交換的實驗,并探索了堿性雙核離子液體[mim]2C4Im2在微管反應器內的催化效果。結果表明,該種離子液體微管內催化效果較差,需要進一步優(yōu)化離子液體制備工藝,并選擇合適的反應條件。
[Abstract]:With the depletion of fossil energy and the increasingly serious environmental pollution, the research of biodiesel has gradually become a hot spot. The production intensity of conventional batch reaction for biodiesel is much lower than that of continuous production, and the production energy consumption is too large due to poor solubility of raw oil and methanol, low reaction rate and poor mass transfer effect. At the same time, the treatment of acid-base catalyst needs a lot of water washing, so it is difficult to recover. The microtube reactor has large specific surface area and good heat and mass transfer performance, which can ensure the uniform distribution of materials, keep the temperature of reaction system constant, and improve mass transfer in multiphase reaction. It has a good prospect of industrial application in enhancing reaction process and improving safety. Ionic liquids are considered to be one of the most promising green solvents and catalysts in the 21st century because of their advantages such as green pollution, easy separation from biodiesel, recyclability and so on. It has a broad application prospect in the field of catalytic transesterification to prepare biodiesel. Therefore, it is of great significance to study the preparation of biodiesel catalyzed by ionic liquids in microtubules. In this paper, the physical and chemical properties of soybean oil were analyzed, and the composition ratio of each component in the raw material was determined. The relative molecular weight of soybean oil was calculated to be 870.31g mol-1,. The quantitative analysis method of biodiesel with methyl undecanoate as internal standard was determined based on gas chromatography. Then the batch catalytic reaction of biodiesel with traditional acid-base catalyst and solid catalyst was carried out. The results showed that the catalytic yield of Koh could reach 90.67 under suitable conditions. The effects of residence time, reaction temperature, molar ratio of alcohol-oil and catalyst on the transesterification of soybean oil and methanol were investigated by using PTFE microtubules as microreactors. The experiment was designed by response surface method and the experimental results were analyzed by Design-Expert to investigate the interaction between various factors on biodiesel yield. The optimum reaction conditions of transesterification catalyzed by KOH in microtubule reactor were determined as follows: residence time 100 s, reaction temperature 58 鈩，

本文編號：2209530