年產(chǎn)5萬(wàn)噸生物柴油生產(chǎn)工藝設(shè)計(jì)畢業(yè)論文-資料下載頁(yè)

　　

【正文】 l be alcohol and organic acid into the corresponding. Such as CH3COOCH2CH3 + NaOH → CH3COOH + CH3CH2OH, inorganic acid esters will be hydrolyzed under the conditions of the corresponding acids and alcohols: CH3COOCH2CH3 + H2O → (conditions H +) CH3COOH + CH3CH2OH Responses: Are reversible, in general, the reaction is not plete, in accordance with equilibrium theory, to improve the yield of ester, need a ponent separated from the product or the reactants approach one of these ponents over the direction of the reaction is. Substitution reaction is Principle of reaction: Reaction mechanism: In the esterification reaction, there is a reversible equilibrium reaction step. Step ② is the controlling step of esterification, and hydrolysis steps ④ is the control step. This reaction is SN2 reaction, after the addition elimination process. Approach using isotope labeling confirmed alcohol esterification water is generated from hydroxy carboxylic acids and alcohols hydrogen. However, the esterification of carboxylic acids with tertiary alcohol is alcohol alkoxy bond breaking occurred in the middle carbocations generated. In the esterification reaction, the alcohol as a nucleophile to the carboxyl carbonyl nucleophilic attack, in the presence of proton acid, carbonyl carbon more electrondeficient and it is conducive to alcohol and nucleophilic addition. Without the presence of acid, acid esterification with alcohol difficult. [19] Typical reaction: Generation of ethanol and acetic acid esterification with aromatic odor of ethyl acetate, is the manufacture of dyes and pharmaceutical raw materials. In some dishes the cooking process, if both the vinegar and wine, will be part of the esterification reaction of aromatic esters, the dishes taste even more delicious. If you want response to industry requirements, the need to sulfuric acid as the catalyst, sulfuric acid and absorb the water produced in reaction to the esterification reaction is more thorough. Reaction equation is as follows: Esterification reaction of acetic acid ethyl equation: CH3COOH + CH3CH2OH → CH3COOC2H5 + H2O (reversible reaction, heating, concentrated sulfuric acid catalyst) Methanol and esterification of terephthalic acid, dimethyl terephthalate is generated, and dimethyl terephthalate with ethylene glycol ester exchange reaction occurs, you can generate polyethylene terephthalate, that is, Polyester. Alcohols and inorganic acids can be carried out esterification reaction such as methanol and sulfuric acid dimethyl sulfate, is a methylation reagent for the introduction of methyl carbohydrates. [3] Response Type: Fischer esterification Esterification reaction is generally reversible. Traditional esterification technology is the use of acid and alcohol in the acid (usually sulfuric acid) was refluxed catalyzed reaction. This reaction is also known as Fischer esterification. The role of concentrated sulfuric acid catalyst and loss control agent, which can be subcarboxylic acid carbonyl substrate, and enhance the electrophilic carbonyl carbon, making the reaction rate accelerated。 they also remove the reaction byproducts of water, to improve the yield of ester. If the material is low in acid and alcohol, soluble in water, the reaction to the reaction mixture after adding water (if necessary by adding saturated sodium carbonate solution), and the reaction solution placed in a separatory funnel for separating handling, collection is difficult the upper layer of watersoluble ester, which ester purification reaction. The role of sodium carbonate reacts with the carboxylic acid salt, carboxylic acids increase the solubility and reduce the solubility of esters. If the product of a lower boiling point esters, can also keep the ester in the reaction distillation, the reaction balance right, and condensation to collect volatile esters. But a few esterification reaction, the acid or alcohol hydroxyl proton of the water away, generate positive ions or acyl carbocation intermediate, the intermediate and then reacts with the alcohol or acid ester. These reactions do not follow the ahydroxy acid, a hydrogen alcohol rule. Carboxylic acid chloride and then through the reaction of esters with alcohols. Reactive than the carboxylic acid chloride stronger, so this method is monly used methods Preparation of esters, the yield generally higher than direct esterification. For the less reactive acyl halides and alcohols, can be added a small amount of alkali, such as sodium hydroxide or pyridine. H3CCOCl + HOCH2CH3 → H3CCOOCH2CH3 + HCl carboxylic acid anhydride and then through the reaction of esters with alcohols. Carboxylic acid salt, and then through the reaction of esters with alkyl halides. Reaction mechanism is a carboxylic acid anion on the αcarbon halogenated nucleophilic substitution reaction. Steglich esterification Carboxylic acid with DCC and a small amount of alcohol in the presence of DMAP esterification. This method is especially suitable for esterification of tertiary alcohols. DCC is the reaction of the loss control agent, DMAP esterification is monly used catalyst. Yamaguchi esterification 2,4,6 trichloro benzoyl chloride reacts with the carboxylic acid substrate, activated carboxylic acid mixed anhydride, followed by a smooth function with alcohol ester. DMAP as a catalyst for esterification. [20] 外文翻譯酯化反應(yīng) 酯化反應(yīng)，是一類有機(jī)化學(xué)反應(yīng)，是醇跟羧酸或含氧無(wú)機(jī)酸生成酯和水的反應(yīng)。分為羧酸跟醇反應(yīng)或無(wú)機(jī)含氧酸跟醇反應(yīng)和無(wú)機(jī)強(qiáng)酸跟醇的反應(yīng)兩類。羧酸跟醇的酯化反應(yīng)是可逆的，并且一般反應(yīng)極緩慢，故常用濃硫酸作催化劑。多元羧酸跟醇反應(yīng)，則可生成多種酯。無(wú)機(jī)強(qiáng)酸跟醇的反應(yīng)，其速度一般較快。典型的酯化反應(yīng)有乙醇和醋酸的反應(yīng)，生成具有芳香氣味的乙酸乙酯，是制造染料和醫(yī)藥的原料。酯化反應(yīng)廣泛的應(yīng)用于有機(jī)合成等領(lǐng)域。基本簡(jiǎn)介：醇跟羧酸或含氧無(wú)機(jī)酸生成酯和水，這種反應(yīng)叫酯化反應(yīng)。 分兩種情況：羧酸跟醇反應(yīng)和無(wú)機(jī)含氧酸跟醇反應(yīng)。羧酸跟醇的反應(yīng)過(guò)程一般是：羧酸分子中的羥基與醇分子中羥基的氫原子結(jié)合成水，其余部分互相結(jié)合成酯。這是曾用示蹤原子證實(shí)過(guò)的。口訣：酸去羥基醇去羥基氫。 羧酸跟醇的酯化反應(yīng)是可逆的，并且一般反應(yīng)極緩慢，故常用濃硫酸作催化劑。多元羧酸跟醇反應(yīng)，則可生成多種酯。如乙二酸跟甲醇可生乙二酸氫甲酯或乙二酸二甲酯。 HOOC—COOH+CH3OH→HOOC—COOCH3+H2O 無(wú)機(jī)強(qiáng)酸跟醇的反應(yīng)，其速度一般較快，如濃硫酸跟乙醇在常溫下即能反應(yīng)生成硫酸氫乙