本文選題：2 + 3-戊二酮　； 參考：《西華師范大學(xué)》2017年碩士論文

【摘要】：2,3-戊二酮為黃綠色油狀液體,主要用作食品香精的原料,明膠硬化劑,相片的粘結(jié)劑等。其天然品存在于芬蘭松等精油中,遠(yuǎn)不能滿足需求。現(xiàn)有的合成方法有:1)在鹽酸羥胺存在下,用氮?dú)獗Ｗo(hù),將甲基丙酮用過量亞硝酸鈉和稀鹽酸氧化而制得。2)由羥基丙酮與己醛在酸性催化下通過縮合反應(yīng)得到。但上述兩種合成方法均采用了大量的液體酸,生產(chǎn)過程廢酸排量較大,對(duì)環(huán)境存在著較大的危害。因而,2,3-戊二酮的清潔生產(chǎn)在當(dāng)下具有緊迫性。近年來,生物質(zhì)及其衍生物由于具有可持續(xù)性、可再生性和綠色環(huán)保性,因此其開發(fā)利用成為重要的研究課題之一,受到國(guó)內(nèi)外的廣泛關(guān)注�；诖�,本論文選擇生物基乳酸為原料,通過催化縮合方式合成2,3-戊二酮展開研究,旨在探索一條2,3-戊二酮的清潔生產(chǎn)路線。2,3-戊二酮的合成存在的主要問題在于催化劑的表面酸堿位與縮合反應(yīng)不匹配,導(dǎo)致反應(yīng)選擇性低;活性組分在反應(yīng)過程中易于流失,導(dǎo)致穩(wěn)定性較差。本文從催化劑分子設(shè)計(jì)思路出發(fā),來構(gòu)建縮合反應(yīng)催化劑,結(jié)合現(xiàn)代表征手段探明催化劑表面酸堿位與縮合反應(yīng)活性之間的關(guān)系,深入探討催化劑的制備條件與反應(yīng)工藝條件對(duì)反應(yīng)的影響,在此基礎(chǔ)上,提出了可能的反應(yīng)機(jī)理。本文具體的研究?jī)?nèi)容如下:催化劑的制備采用浸漬法和沉淀法。催化劑的表征方面,主要采用了X-射線粉末衍射(XRD)、紅外(FT-IR)對(duì)催化劑結(jié)構(gòu)進(jìn)行了表征;采用EDX對(duì)催化劑的元素組成進(jìn)行了分析;采用N2-物理吸脫附(BET)、掃描電鏡(SEM)等對(duì)催化劑的織構(gòu)、外貌進(jìn)行了分析;采用化學(xué)吸附-脫附(CO2-TPD/NH3-TPD)研究了催化劑表面的酸堿位分布及密度。催化劑活性評(píng)價(jià)采用固定床微反應(yīng)裝置進(jìn)行氣固催化反應(yīng)活性評(píng)價(jià)。本論文主要研究了二氧化硅負(fù)載的堿金屬硝酸鹽,銫摻雜的鎂鋁復(fù)合物和銫摻雜的羥基磷灰石三大體系。催化劑體系1:二氧化硅通過浸漬法將不同堿金屬硝酸鹽負(fù)載其表面,并將該催化劑用于乳酸縮合反應(yīng)生成2,3-戊二酮的反應(yīng)中�？疾炝朔磻�(yīng)溫度、硝酸鹽的負(fù)載量等對(duì)乳酸縮合反應(yīng)的影響。以4.4%(x,摩爾分?jǐn)?shù))CsNO3/SiO2為催化劑,在反應(yīng)溫度為300℃條件下,2,3-戊二酮的收率達(dá)54.1%。關(guān)聯(lián)催化劑的活性與CO2-TPD表征的堿性發(fā)現(xiàn),堿性位是影響該反應(yīng)的關(guān)鍵,堿性位越多,活性越好。催化劑體系2:雖然前述催化劑體系對(duì)縮合反應(yīng)的初始活性比較高,但穩(wěn)定性較差,其原因在于活性組分Cs在催化反應(yīng)過程中的流失。為了解決催化劑的穩(wěn)定性,我們采用了原位分子組裝手段,將活性組分Cs摻雜到載體結(jié)構(gòu)中去,為此制備出了一系列摻雜型的鎂鋁復(fù)合物催化劑。并考察了鎂鋁比對(duì)催化劑性能的影響。在選用最優(yōu)選的催化劑,在反應(yīng)溫度為300℃條件下,2,3-戊二酮的收率達(dá)30%,收率不高,但其穩(wěn)定性較前一個(gè)體系相比有了較大的提高。催化劑體系3:盡管催化劑體系2的催化劑活性不高,但穩(wěn)定性較好,表明分子組裝手段摻雜活性組分Cs有可行性。在此思路指導(dǎo)下,我們采用分子組裝手段制備了Cs摻雜的羥基磷灰石催化劑�？疾炝遂褵郎囟群拖跛徜C的摻雜量這兩個(gè)重要影響因素對(duì)催化劑的性能的影響。此外,還就反應(yīng)工藝條件中的反應(yīng)溫度、原料乳酸的進(jìn)樣速率和乳酸濃度也進(jìn)行了優(yōu)化。在優(yōu)選的最佳比例和最佳煅燒溫度下,反應(yīng)溫度為290攝氏度條件下,2,3-戊二酮的收率可達(dá)65%左右;更為重要的是催化劑的穩(wěn)定性很好,達(dá)40 h。通過對(duì)催化劑表征發(fā)現(xiàn),催化劑表面的酸-堿位是影響催化活性的關(guān)鍵,堿位/酸位比為7-8,催化性能好,基于此,提出了乳酸縮合反應(yīng)的酸堿協(xié)同催化反應(yīng)機(jī)理。
[Abstract]:2,3- glutarone is a yellow green oil like liquid, which is mainly used as the raw material of the flavor of food, gelatin sclerosing agent, and the binder of the photo. Its natural products are found in the essential oil of Finland pine and so on. The existing synthetic methods are: 1) in the presence of hydroxylamine hydrochloride, it is protected by nitrogen, and the methyl acetone is oxidized by excessive sodium nitrite and dilute hydrochloric acid. .2) is obtained by the condensation reaction of hydroxyl acetone and acetaldehyde under the acid catalysis. However, the two synthetic methods have adopted a large amount of liquid acid. The production process has a large amount of waste acid and has a great harm to the environment. Therefore, the clean production of 2,3- glutarone is urgent at the moment. In recent years, biomass and its derivatives are from Because of its sustainability, renewable and green environmental protection, its development and utilization has become one of the most important research topics, and is widely concerned at home and abroad. Based on this, this paper chooses biologically based lactic acid as the raw material and syntheses 2,3- glutarone through catalytic condensation. The purpose of this study is to explore a clean production route of 2,3- glutarone.2 The main problem of the synthesis of 3- glutarone is that the surface acid base position of the catalyst is not matched with the condensation reaction, and the reaction selectivity is low. The active component is easily lost during the reaction process and leads to the poor stability. The relationship between the surface acid base position of the chemical agent and the activity of condensation reaction, the influence of the preparation conditions of the catalyst and the reaction process conditions on the reaction are deeply discussed. On this basis, the possible reaction mechanism is put forward. The specific content of this paper is as follows: the preparation of the catalyst is made by impregnation and precipitation. The structure of the catalyst was characterized by X- ray powder diffraction (XRD) and infrared (FT-IR); the composition of the catalyst was analyzed with EDX; the texture and appearance of the catalyst were analyzed by N2- physical desorption (BET), scanning electron microscope (SEM) and so on. The acid base of the catalyst surface was studied by chemical adsorption desorption (CO2-TPD/NH3-TPD). A fixed bed microreaction device was used to evaluate the activity of gas solid catalytic reaction. This paper mainly studied three major systems: silica loaded alkali metal nitrate, caesium doped magnesia aluminum complex and cesium doped hydroxyapatite. The catalyst body 1: silica was impregnated with different alkaloids. The metal nitrate is loaded on its surface, and the catalyst is used in the reaction of lactic acid condensation to produce 2,3- glutarone. The effect of reaction temperature, nitrate load and so on on the condensation reaction of lactic acid is investigated. The yield of 2,3- glutarone is 54.1%. with 4.4% (x, mole fraction) CsNO3/SiO2 as the catalyst and the yield of 2,3- glutarone at the reaction temperature of 54.1%. The activity of the catalyst and the alkaline discovery of the CO2-TPD showed that the basic position is the key to the reaction. The more basic position and the better the activity, the catalyst system 2:, although the initial activity of the catalyst system is high, but the stability is poor, the reason is the loss of the active component Cs during the catalytic reaction. The stability of the chemical agent, we used the in situ molecular assembly method, doped the active component Cs into the carrier structure, and prepared a series of doped magnesium aluminum complex catalysts. The effect of magnesium aluminum ratio on the performance of the catalyst was investigated. The optimum catalyst was selected and the 2,3- glutarone was used at the reaction temperature of 300. The yield is 30%, the yield is not high, but the stability of the catalyst system has been greatly improved compared with the previous system. Although the catalyst system 3: is not highly active in the catalyst system 2, the stability is good. It shows that the molecular assembly method is feasible to doping the active component Cs. Under the guidance of this train of thought, we have prepared the Cs doping by molecular assembly. The effect of the two important factors of calcining temperature and the amount of caesium nitrate on the performance of the catalyst was investigated. In addition, the reaction temperature in the reaction conditions, the injection rate and the concentration of lactic acid were also optimized. At optimum proportion and the optimum calcination temperature, the reaction temperature was obtained. Under the condition of 290 degrees Celsius, the yield of 2,3- pentan is about 65%. More importantly, the stability of the catalyst is very good. Up to 40 h. through the characterization of the catalyst, the acid base position on the surface of the catalyst is the key to the catalytic activity, the base / acid ratio is 7-8, and the catalytic activity is good. Based on this, the acid base coordination of lactic acid condensation reaction is put forward. The mechanism of the same catalytic reaction.
【學(xué)位授予單位】：西華師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：O623.523

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 苗琪;;探究生物質(zhì)鍋爐技術(shù)發(fā)展現(xiàn)狀以及未來發(fā)展趨勢(shì)[J];中國(guó)石油和化工標(biāo)準(zhǔn)與質(zhì)量;2016年13期

2 曹玉錦;咸漠;劉會(huì)洲;;大宗化學(xué)品可持續(xù)化工—生物融合轉(zhuǎn)化探析[J];中國(guó)科學(xué):化學(xué);2015年05期

3 袁信;周鍵;田森林;蔣明;寧平;張秋林;;過渡金屬負(fù)載γ-Al_2O_3對(duì)HCN催化水解性能的影響[J];環(huán)境科學(xué)研究;2014年12期

4 喬昱;;闡述綠色化學(xué)工程與工藝對(duì)化學(xué)工業(yè)節(jié)能發(fā)展的作用[J];山東工業(yè)技術(shù);2014年16期

5 王赤炎;呂學(xué)功;王麗紅;;綠色化學(xué)中的智能溶劑[J];唐山師范學(xué)院學(xué)報(bào);2012年05期

6 李新華;楊強(qiáng);王琳;劉爽;;銀杏果淀粉與玉米、馬鈴薯淀粉理化性質(zhì)的比較研究[J];食品工業(yè)科技;2012年09期

7 張兵;張寧;李丹;徐超;;江蘇省秸稈類農(nóng)業(yè)生物質(zhì)能源分布及其利用的效益[J];長(zhǎng)江流域資源與環(huán)境;2012年02期

8 李擁新;王興鵬;;黑龍江省生物質(zhì)能源開發(fā)可行性及前景[J];中國(guó)電力教育;2011年36期

9 王兵兵;薛志欣;付永強(qiáng);孔慶山;紀(jì)全;夏延致;;海洋生物質(zhì)纖維材料的開發(fā)與研究[J];高分子通報(bào);2011年12期

10 吳軍;;原子經(jīng)濟(jì)性與“綠色化學(xué)”[J];高科技與產(chǎn)業(yè)化;2011年08期

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