本文關(guān)鍵詞： 脂肪醇 油脂 選擇性加氫 甲醇供氫 Cu/SiO_2催化劑　出處：《華東師范大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：脂肪醇是一種廣泛應(yīng)用、大規(guī)模生產(chǎn)的化學(xué)品,主要應(yīng)用于洗滌劑、潤滑劑、化妝品、個(gè)人護(hù)理產(chǎn)品、藥物,以及在化妝品和食品工業(yè)中用作潤滑基質(zhì)、軟化劑和增稠劑,在塑料產(chǎn)業(yè)中用為聚合劑。以天然油脂為原料制備天然脂肪醇的傳統(tǒng)方法通常為兩步法,存在著操作繁瑣、設(shè)備復(fù)雜、反應(yīng)條件苛刻、需要消耗大量的氫氣等問題。為了解決目前使用的工藝存在的弊端,我們設(shè)計(jì)了一種全新的制備脂肪醇的方法,即在無氫條件下一鍋法實(shí)現(xiàn)甲醇和油脂共活化的路線,利用甲醇原位生成的氫氣供給給油脂進(jìn)行選擇性加氫生成脂肪醇。我們從甲醇脫氫反應(yīng)入手,設(shè)計(jì)了一種能有效促進(jìn)甲醇原位產(chǎn)氫的Cu基催化劑(由沉積沉淀法制備,氨水為沉淀劑),確定了催化劑的載體以及溫度等因素對(duì)該反應(yīng)的影響。通過對(duì)催化劑的一系列表征,結(jié)合分析氣液相反應(yīng)產(chǎn)物,得出了甲醇脫氫反應(yīng)機(jī)理,得到了純度高達(dá)87%的氫氣,且副產(chǎn)物CO較少,僅有12%,少量的CO不易毒化金屬活性組分致使催化劑失活。隨后,我們進(jìn)一步耦合甲醇脫氫反應(yīng)與脂肪酸甲酯加氫反應(yīng),考察了水熱法制備的Cu/SiO_2催化劑在該反應(yīng)體系下的催化活性,確定了能夠原位產(chǎn)生的氫氣在反應(yīng)體系內(nèi)部轉(zhuǎn)移的反應(yīng)機(jī)理,最后在一鍋法中實(shí)現(xiàn)了無氫條件下由油脂與甲醇這兩種生物質(zhì)共活化生成脂肪醇的過程。通過分析確定了催化劑中的Cu2O和Cu0兩種銅組分共同組成催化甲醇脫氫反應(yīng)的活性組分,Cu0則是加氫反應(yīng)的活性中心。結(jié)合氣液相反應(yīng)產(chǎn)物,我們還提出了該反應(yīng)過程的催化路徑。綜上,我們開發(fā)了一種全新的一鍋法由油脂制備脂肪醇的方法,即在Cu/SiO_2催化劑的作用下,將甲醇原位生成的氫氣供給給由油脂與甲醇反應(yīng)生成的脂肪酸甲酯進(jìn)行選擇性加氫,生成高選擇性的脂肪醇。在本課題工作中,我們設(shè)計(jì)了一種既能催化甲醇脫氫、又能催化脂肪酸甲酯選擇性加氫過程的Cu基催化劑,同時(shí)闡明了這兩個(gè)單獨(dú)過程及耦合后整個(gè)過程的反應(yīng)機(jī)理。這種方法簡單高效,原子經(jīng)濟(jì)性高,且符合綠色化學(xué)及化工過程的定義,所制備的高品質(zhì)脂肪醇也更為清潔綠色。
[Abstract]:Fatty alcohol is a widely used, mass-produced chemical that is mainly used in detergents, lubricants, cosmetics, personal care products, medicines, and in the cosmetics and food industries as a lubricant, softener and thickener, The traditional method of preparing natural fatty alcohol from natural oil is usually two-step method, which has complicated operation, complicated equipment and harsh reaction conditions. In order to solve the disadvantages of the current process, we have designed a new method for the preparation of fatty alcohols, that is, the one-pot method to realize the co-activation of methanol and oil under the condition of no hydrogen. Fatty alcohols were prepared by selective hydrogenation of oil with hydrogen from methanol in situ. Based on the dehydrogenation of methanol, a Cu-based catalyst was designed to effectively promote in situ hydrogen production from methanol. The influence of catalyst carrier and temperature on the reaction was determined. The mechanism of methanol dehydrogenation was obtained by a series of characterization of catalyst and analysis of the products of gas-liquid phase reaction. Hydrogen with purity as high as 87% was obtained, and the by-product CO was only 12%. The catalyst was deactivated by a small amount of CO not easily toxic to metal active components. Subsequently, we further coupled the methanol dehydrogenation reaction with the hydrogenation of fatty acid methyl ester. The catalytic activity of Cu/SiO_2 catalyst prepared by hydrothermal method in this reaction system was investigated, and the mechanism of hydrogen transfer in situ was determined. Finally, fatty alcohols were co-activated by two kinds of biomass, oil and methanol, in a one-pot process. The two copper components of Cu2O and Cu0 in the catalyst were determined to constitute the reverse reaction of methanol dehydrogenation. The active component Cu0 is the active center of hydrogenation reaction. In summary, we have developed a novel one-pot method for the preparation of fatty alcohols from oils, that is, in the presence of Cu/SiO_2 catalysts. The hydrogen produced in situ from methanol was supplied to the fatty acid methyl ester from the reaction of oil and methanol for selective hydrogenation to produce a high selectivity fatty alcohol. In this work, we designed a kind of catalyst for the dehydrogenation of methanol. Cu-based catalyst can also catalyze selective hydrogenation of fatty acid methyl ester. The reaction mechanism of these two separate processes and the whole process after coupling are also explained. This method is simple and efficient, and has high atomic economy. In accordance with the definition of green chemistry and chemical process, the high quality fatty alcohol prepared is cleaner and greener.
【學(xué)位授予單位】：華東師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TQ223

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 常佳敏;徐瑩;馬隆龍;王鐵軍;張琦;陳冠益;;生物油酯化-加氫提質(zhì)制備醇酯類燃料[J];農(nóng)業(yè)工程學(xué)報(bào);2016年05期

2 陳冠益;孔椺;徐瑩;李婉晴;馬隆龍;顏蓓蓓;陳鴻;;生物質(zhì)化學(xué)制氫技術(shù)研究進(jìn)展[J];浙江大學(xué)學(xué)報(bào)(工學(xué)版);2014年07期

3 張佳光;寇元;;脂肪醇合成新方法[J];石油化工;2013年09期

4 王連鴛;徐文浩;楊基礎(chǔ);;超臨界甲醇在化學(xué)反應(yīng)中的應(yīng)用[J];化學(xué)進(jìn)展;2010年05期

5 高伯良;聶開立;王芳;鄧?yán)?譚天偉;;椰子油為原料酶法制備脂肪酸甲酯[J];北京化工大學(xué)學(xué)報(bào)(自然科學(xué)版);2010年01期

6 席靖宇,呂功煊;NiCu/ZnO催化劑的甲醇裂解制氫研究[J];分子催化;2001年03期

，

本文編號(hào)：1542621