本文選題：乙酸乙酯　切入點(diǎn)：金催化劑　出處：《昆明理工大學(xué)》2016年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：乙酸乙酯(Ethyl Acetate,簡(jiǎn)稱(chēng)EA),是一種環(huán)境友好型工業(yè)溶劑,同時(shí)它也是食用香料的合成香精之一。目前,國(guó)內(nèi)較為成熟的生產(chǎn)乙酸乙酯的工藝為乙酸酯化法,但該法所采用的催化劑是腐蝕性極強(qiáng)的濃硫酸,這使得生產(chǎn)設(shè)備的腐蝕情況比較嚴(yán)重,并伴隨著環(huán)境污染較大和后期處理困難等問(wèn)題。與之相比,以新型催化劑的研發(fā)為核心的乙醇脫氫法只需以乙醇為原料即可完成生產(chǎn),同時(shí)乙醇可以通過(guò)農(nóng)作物發(fā)酵而來(lái),不必完全依賴(lài)不可再生資源來(lái)制造。因此,若能開(kāi)發(fā)出穩(wěn)定、高效的催化劑來(lái)推動(dòng)乙醇脫氫反應(yīng)的工業(yè)化,就可以大幅提升乙醇脫氫法在乙酸乙酯生產(chǎn)中的競(jìng)爭(zhēng)地位。本論文工作以人工合成的層狀雙羥基金屬氫氧化物(簡(jiǎn)稱(chēng)LDHs)以及從天然膨潤(rùn)土經(jīng)過(guò)提純改型鈉化的鈉基蒙脫石(簡(jiǎn)稱(chēng)NaMMT)為載體,利用本課題組前期研究的金催化劑制備方法,獲得了不同類(lèi)型的層狀載體負(fù)載的金催化劑,并將其首次應(yīng)用于催化乙醇液相氧化反應(yīng),系統(tǒng)研究了包括載體的類(lèi)型、金的負(fù)載量、催化劑的用量、催化劑的焙燒溫度、以及乙醇液相反應(yīng)條件(反應(yīng)溫度、反應(yīng)壓力、反應(yīng)時(shí)間)等因素對(duì)催化活性的影響。實(shí)驗(yàn)研究結(jié)果表明：(1)按照金的理論負(fù)載量為2wt%,將納米金分別負(fù)載在LDHs載體和蒙脫石載體上制備的金催化劑,在乙醇的液相氧化體系中表現(xiàn)出的催化性能差異較大,其中蒙脫石負(fù)載的催化劑基本不具有活性,而三種不同層板組成的LDHs負(fù)載的金催化劑的活性都比較高。(2)以金溶膠負(fù)載在LDHs載體上所制備的2wt%-Au-MgAl-LDHs為催化劑,通過(guò)單因素實(shí)驗(yàn)以及多因素的響應(yīng)曲面分析法優(yōu)化乙醇選擇性氧化反應(yīng)的條件(反應(yīng)溫度、反應(yīng)壓力和反應(yīng)時(shí)間),得出的優(yōu)化反應(yīng)條件為：反應(yīng)溫度128℃,反應(yīng)壓力5MPa,反應(yīng)時(shí)間7h,在此最適宜反應(yīng)條件下,乙醇的轉(zhuǎn)化率為58%,乙酸乙酯的選擇性為87%。(3) 2wt%Au-MgAl-LDHs催化劑在多次利用后依然具有較高的活性,在128℃,5Mpa的反應(yīng)條件下反應(yīng)7h,重復(fù)使用4次后,該催化劑依然可以使乙醇的轉(zhuǎn)化率達(dá)到50%,乙酸乙酯的選擇性達(dá)到86%,表明該催化劑對(duì)乙醇液相選擇氧化反應(yīng)具有良好的穩(wěn)定性。
[Abstract]:Ethyl Acetate (EAC) is a kind of environment-friendly industrial solvent, and it is also one of the synthetic flavours of edible spices. At present, the mature process of producing ethyl acetate in China is acetic acid esterification. However, the catalyst used in the method is highly corrosive concentrated sulfuric acid, which makes the corrosion of the production equipment more serious, and accompanied by the environmental pollution and the difficulty of post-treatment and other problems. The ethanol dehydrogenation process with the core of the research and development of the new catalyst can be completed by using ethanol as the raw material, and ethanol can be produced through the fermentation of crops without having to rely entirely on non-renewable resources to produce it. Therefore, if it can be developed steadily, Highly efficient catalysts to promote the industrialization of the dehydrogenation of ethanol, In this paper, the layered dihydroxyl metal hydroxides (LDHs) and sodium from natural bentonite were purified from natural bentonite, which can greatly enhance the competitive position of ethanol dehydrogenation in ethyl acetate production. Base montmorillonite (NaMMT) as carrier, Different kinds of layered supported gold catalysts were obtained by using the preparation method of gold catalysts previously studied by our research group. The catalysts were first applied to the liquid phase oxidation of ethanol. The types of supports were systematically studied. The amount of gold supported, the amount of catalyst used, the calcination temperature of catalyst, and the reaction conditions of ethanol liquid phase reaction (reaction temperature, reaction pressure, reaction pressure), The experimental results show that the gold catalyst prepared on the LDHs and montmorillonite supports is loaded on the LDHs and montmorillonite respectively according to the theoretical loading amount of gold at 2 wts. the effect of reaction time and other factors on the catalytic activity is studied. In the liquid phase oxidation system of ethanol, the catalytic performance of montmorillonite was different, and the catalyst supported on montmorillonite had little activity. The activity of the three kinds of gold catalysts supported on LDHs with different laminates was higher than that of the gold sol-supported gold catalysts. The gold sol supported on the LDHs support was used as the catalyst for the preparation of 2wt- Au-MgAl-LDHs. The conditions (reaction temperature, reaction pressure and reaction time) of ethanol selective oxidation reaction were optimized by single factor experiment and multi-factor response surface analysis. The optimum reaction conditions were obtained as follows: reaction temperature 128 鈩，

本文編號(hào)：1636106