醋酐生产工艺外文翻译

化工与材料工程学院毕业设计（论文）外文翻译吉林化工学院成人教育学院毕业设计外文翻译8000吨/年醋酐装置精馏工段工艺设计学生学号 09360106学生姓名 刘雪婷专业班级111化学工程与工艺指导教师丁斌教授完成日期2011.09.03吉林化工学院JilinInstituteofChemicalTechnologyAcetic anhydride production process Acetic anhydride is a colorless volatile, with a strong irritating smell and corrosiveness liquid. Name of acetic anhydride, molecular formula C4H6O3, the flash point of 64.4 DEG c. Density of 1.082 0g / cm3. Melting point - 74.13 DEG c. The boiling point of 138.63 DEG c. The refractive index nD 1.390. 20 degrees of viscosity of 0.91 mPa? S. Spontaneous ignition temperature of 388.9 DEG c. Soluble in cold water, in water is decomposed into acetic acid, ethyl acetate and ethanol production. Soluble in chloroform, ether and benzene. Toxic, eye and mucosa has a strong irritating, mass concentration of 0.36 mg / m3 when the eye irritation; 0.18mg / m3, can change a persons brain electrical image, can cause tissue protein modification. The steam stimulation is stronger, extremely easy to burn the skin and eyes, such as frequent exposure can cause dermatitis and chronic conjunctivitis. On rat oral LD50 was 1780 mg / kg. When spilled and or adhesion to the skin, to immediately with water or 2% washing soda, systemic poisoning should be timely medical treatment. Air max allowable volume fraction 5 u L / L. Acetic anhydride is the country to encourage the development of basic organic chemical raw materials, mainly used for the production of cellulose acetate, of which two cellulose acetate is used in the manufacture of cigarette filter tip and plastic, three cellulose acetate is the manufacturing of advanced film material, is widely used in medicine, pesticides, dyes, military, spices, metal finishing industries.Acetic anhydride is precursor products, acetic anhydride production, management must be in the public security organ for archival filing certification, enterprises sold every batch of goods to perform detailed registration, and to the public security organ for the record. According to the legal provisions, to undocumented units 200 kg acetic anhydride, will be sentenced to 3 years imprisonment. Industrialization of acetic anhydride production process has three kinds: the oxidation of acetaldehyde, ethylene ketone and methyl acetate carbonylation. Acetaldehyde oxidation technology source for the Canadian Sha Winigan chemical company. The production process is as follows: acetaldehyde and oxygen at 60 degrees C, 101 kPa or 70 degrees C, 600-700kPa under the conditions of the oxidation reaction, oxygen or air as the oxidant, using ethyl acetate as solvent, cobalt acetate as catalyst, acetic acid copper as promoter. Acetaldehyde and oxygen ( in excess of about 1%-2%) reaction is first generated peroxy acetic acid, acetic acid and acetaldehyde reaction of acetic anhydride and acetic acid. Under this condition, the conversion rate of acetaldehyde acetic anhydride and acetic acid production rate is 95%, the mass ratio of 56: 44. The total yield of 70%-75% acetic anhydride. By changing the processing conditions, can improve the yield of acetic anhydride. Reaction equation:CH3CHO+O2 - CH3COOOH;CH3COOOH+CH3CHO CH3COOOCH ( OH )CH3 ( single peroxy acetic ester );CH3COOOCH ( OH ) CH3 - ( CH3CO ) 2O+H2O;CH3COOOCH ( OH CH3 2CH3COOH ). Acetaldehyde acetic anhydride consumption per ton of 1.165 T, 2300 m3 standard air. Acetaldehyde oxidation method has the advantages of simple process, technology is mature, but the serious corrosion, high consumption, has gradually been eliminated. In foreign countries have been carbonylation of methyl acetate and vinyl ketone method alternative. China Shanghai Chemical Reagent Factory of this device has been in a state of production. Vinyl ketone law in accordance with the different materials can be divided into: acetic acid and acetone method. Acetic acid process technology from Germany Wacher chemical company. The production process is as follows: in the first step, the acetic acid in 700-750 C, 10-20kPa pressure and 0.2%-0.3% phosphoric acid three ethyl ester (by acetic acid quality plan) as catalyst under the conditions of dehydration, cracking ethylene ketone acetate made, conversion rate is about 85%-90%, on vinyl ketone selectivity (corporeal quantity meter ) is about 90%-95%. Reaction equation:CH3COOH CH2 = C = O+H2O+147 kJ / mol. The second step is to absorb liquid acetic acid ethylene ketone anhydride generating, by distillation and purification to obtain the product of acetic anhydride, vinyl ketone conversion rate of about 100%. Reaction equation:CH3COOH+CH2 = C = O ( CH3CO ) 2O+62.8kJ / mol. The production process is a German Wacher chemical company to develop a success, and in 1936 achieved industrialization. Two existing production process: One, as the tower process. Using 4 packed tower for synthesis and separation. The consumption of per ton of acetic anhydride as catalyst, acetic acid 1.35t, 1.5-2kg 0.7-1.0kg 100-160kg, ammonia, acetic acid recovery. Secondly, as the liquid ring pump flow. The liquid ring pump for reaction and absorption equipment. The process is simple, being replaced by tower process. Per ton of products consumption quota for acetic acid cracking rate, 1.22 T, 75%, the yield of synthesis of 96%. The production process is as follows: The first step is to acetone in 700-800 C, atmospheric pressure, no catalyst under the conditions of the cleavage reaction. Reaction equation:CH3COCH3 CH2 = C = O+CH4-79.53 kJ / mol. The second step is to absorb the liquid acetic acid ethylene ketone anhydride generating. Reaction equation:CH2 = C = O+CH3COOH ( CH3CO ) 2O+62.8kJ / mol. But in the same scale, acetone and acetic acid, acetone method requires larger cracking furnace, absorption tower and the washing tower, and an increase in cyclic acetone water distillation separation and other auxiliary equipment, the project construction cost is high. At the same time, the production cost is also higher acetone method. Ketene process relative acetaldehyde oxidation and carbonylation of methyl acetate to the process, the process is complex, a lot of side reactions, high energy consumption, low profit. Due to the production technology is mature, abroad in the early construction device using this method, in our country is still widely used. In 1973, Halcon Scientific Development Corporation obtained the carbonylation of methyl acetate to acetic anhydride production of patent. In 1983, the company cooperates with American Eastman-Kodak company built up the first set of the carbonylation synthesis of acetic anhydride production device. Celanese company also has this technology. The production process is as follows: the first is the methanol and acetic acid in sulfuric acid under the action of catalyst to generate methyl acetate, the reaction pressure is normal pressure, reaction temperature of 65-85 C, the acetic acid conversion rate of about 100%. Then, methyl acetate and methanol and carbon monoxide in the methyl iodide and rhodium catalyst or nickel catalysts ( for rhodium catalyst catalytic activity of Ni catalyst is 10 times, so the industrial use of rhodium catalyst ) presence, for carbonylation reaction of acetic anhydride and acetic acid, cogeneration. The reaction pressure is about 2.55 MPa, reaction temperature 180 degrees celsius. The acetic acid / acetic acid ratio can be adjusted according to the requirement. Reaction equation:CH3COOH+CH3OH - CH3COOCH3+H2O;CH3COOCH3+CO ( CH3CO ) 2O;CH3OH+CO - CH3COOH. Methyl acetate carbonylation with a short process, products of good quality, low consumption, less waste discharges etc., represents the advanced level of production technology of acetic anhydride. At present, the main foreign suppliers are used in the process of acetic anhydride. Liquid phase process than gas phase process maturity. British BP company in Halcon and Monsanto synthesis of acetic anhydride carbonylation to acetic acid based on technology, the successful development of the carbonylation of methanol and acetic anhydride - acetic acid process, and on 1987 implementation industrialization ( Figure 1 ( omitted) ). Gas phase carbonylation of Hoechst company in 1986 developed, reaction temperature, 185-216 C, by heterogeneous supported catalysts. The catalyst is a precious metals rhodium, iridium, palladium or rubidium contained in silica, three two aluminum oxide, magnesium oxide, two oxide carrier, which showed the highest activity of rhodium. Gas phase esterification reaction with liquid phase method are the same, and liquid phase carbonylation carbonylation are similar. The difference is: the liquid phase carbonylation of methyl acetate in liquid phase carbonylation reaction; and the gas phase carbonylation reactions in the gas phase, gas phase process were removed from the reaction liquid catalyst recovery. Gas phase process can reduce the loss of rhodium, rhodium is fixed on the carrier without the accident was washed out in the solution. Gas phase process in terms of investment is better than that of liquid phase process, but the project cost is higher. In 2003, Dan group of Jiangsu, Chinese Academy of Sciences and Beijing University three homes, built up the first set of acetic anhydride carbonylation synthesis device, device dimensions is 20000 t / a acetic anhydride . The device can also adjust the production of methyl acetate by Lanzhou Petrochemical Design Institute, engineering general contracting and design, production of acetic anhydride purity of the product reached more than 99.5%, more than 99.9% of methyl acetate. A ton of acetic anhydride consumption quota for methanol acetic acid 0.353 T, 0.604t, CO for 0.340t, Z catalyst 0.44, steam 4.2 T, 147 t water, electric 167kwh, instrument air 300m3. Device operation practice proves, developed by China in this set of acetic anhydride production process is reliable. Acetic anhydride carbonylation synthesis process, reactor by esterification and the carbonylation reactor, methanol and acetic acid in the esterification reactor to generate methyl acetate, methyl acetate in carbonylation reactor and CO synthesis of acetic anhydride. Because the process of catalyst in water, generation acetic anhydride - at the same time, also generates a part of acetic acid. The processes for the production of acetic anhydride mainly, main raw material for CO and methanol, acetic acid. In addition, the process also can directly use the raw materials of methanol and CO in the carbonylation reactor in response to acetic acid, without esterification device. Therefore, the process can be based on market demand for acetic acid, methyl acetate and acetic anhydride products switch. by carbonylation catalyst technology is the most important, Institute of Chemistry Chinese Academy of Sciences after years of research and development and development of the domestic catalyst - multidentate Ji Ji heterozygous rhodium complexes catalyst. And the United States Monsanto developed catalyst, the catalyst has a water content of less. From Jiangsu, the Dan group use, reaction conditions and catalyst abroad basically the same ( reaction pressure 3-6MPa, temperature 160-200 C ), an ideal application. In addition to using rhodium catalyst, the carbonylation synthesis of acetic anhydride process can also be used for other metal catalysts. Although the rhodium catalyst catalytic activity and selectivity for the best, but there are expensive, shortage of resources, recycling costs higher shortcoming. Therefore, many companies have shifted their attention to non noble metal catalysts, which are mainly I A III A B or B, VI, VIII non-noble metals. Among them, nickel catalyst in the reaction conditions such as mild and catalytic properties are obviously superior to other non-noble metal, is a kind of the most development prospect of non noble metal catalysts. Vinyl ketone and carbonyl synthesis process is the production of acetic anhydride used method. From the contrast can be seen in Table 1, ketene process is relatively complex, the product quality is low, the energy consumption is relatively high, high cost, pollution, heavy, small scale. 醋酐生产工艺 醋酐为无色易挥发，具有强烈刺激性气味和腐蚀性液体。学名乙酸酐，分子式为C4H6O3，闪点64.4。密度1.082 0g/cm3。熔点-74.13。沸点138.63。折射率nD 1.390。20粘度0.91 mPa?s。自燃点388.9。溶于冷水，在热水中分解成醋酸，与乙醇生成乙酸乙酯。溶于氯仿、乙醚和苯。有毒，对眼及粘膜具有强烈的刺激性，质量浓度为0.36 mg/m3时即对眼有刺激；0.18mg/m3时，就能改变人的脑电图象，还能引起细胞组织蛋白质变质。其蒸气刺激性更强，极易烧伤皮肤及眼睛，如经常接触会引起皮炎和慢性结膜炎。对大鼠经口LD50为1780 mg/kg。当溅及或粘附于皮肤时，要立即用清水或2%苏打水冲洗，全身中毒时应及时就医诊治。空气中最高容许体积分数5L/L。 醋酐是国家鼓励发展的基本有机化工原料，主要用于生产醋酸纤维素，其中二醋酸纤维素用于制造香烟过滤嘴和塑料，三醋酸纤维素是制造高级感光胶片的材料，还广泛用于医药、染料、农药、军工、香料、金属抛光等行业。 醋酐是“易制毒”产品，醋酐的生产、经营都要依法在公安机关备案取证，企业卖出的每一批商品都要进行详细的备案登记，并到公安机关备案。依据法律规定，卖给无证单位200 kg醋酐，将被判处3年有期徒刑。 工业化的醋酐生产工艺有三种：乙醛氧化法、乙烯酮法和醋酸甲酯羰基化。 乙醛氧化法技术来源为加拿大Sha Winigan化学公司。生产工艺如下：乙醛和氧在60、101 kPa或70、600-700kPa条件下进行氧化反应，用氧气或空气作氧化剂，以醋酸乙酯为溶剂，醋酸钴为催化剂，醋酸铜为促进剂。乙醛与氧气(过量约1%-2%)反应首先生成过氧醋酸，过氧醋酸再与乙醛反应生成醋酐和醋酸。在此条件下，乙醛转化率为95%，醋酐及醋酸产率的质量比为56：44。醋酐的总收率为70%-75%。通过改变工艺条件，可以提高醋酐的产率。反应方程式为： CH3CHO+O2CH3COOOH； CH3COOOH+CH3CHOCH3COOOCH(OH) CH3(单过氧醋酸酯)； CH3COOOCH(OH)CH3(CH3CO)2O+H2O； CH3COOOCH(OH)CH32CH3COOH。 每吨醋酐消耗乙醛1.165 t，标准状态空气2300 m3。乙醛氧化法流程简单，工艺成熟，但腐蚀严重，消耗较高，已逐渐被淘汰。在国外已被醋酸甲酯羰基化和乙烯酮法所替代。我国上海化学试剂总厂这种装置已经处于停产状态。 乙烯酮法按照原料不同又可以分为：醋酸法和丙酮法。 醋酸法技术来源为德国Wacher化学公司。生产工艺如下：第一步，醋酸在700-750、10-20kPa的压力及0.2%-0.3%磷酸三乙酯(按醋酸质量计)作催化剂的条件下，裂解脱水制成乙烯酮，醋酸转化率约为85%-90%，对乙烯酮的选择性(物质的量计)约为90%-95%。反应方程式为： CH3COOHCH2=C=O+H2O+147 kJ/mol。 第二步是液体乙酸吸收乙烯酮生成醋酐，经精馏提纯制得成品醋酐，乙烯酮的转化率约100%。反应方程式为： CH3COOH+CH2=C=O(CH3CO)2O+62.8kJ/mol。 该生产工艺是德国Wacher化学公司开发成功的，并于1936年实现工业化。现有两种生产流程： 其一，为塔式流程。用4个填料塔进行合成与分离。每吨醋酐的消耗定额为，醋酸1.35t，催化剂1.5-2kg，氨0.7-1.0kg，回收醋酸100-160kg。 其二，为液环泵流程。以液环泵为反应及吸收设备。该流程十分简单，正在取代塔式流程。每吨产品的消耗定额为，醋酸1.22 t，裂解率75%，合成收率96%。 生产工艺如下： 第一步是丙酮在700-800、常压、没有催化剂的条件下进行裂解反应。反应方程式为： CH3COCH3CH2=C=O+CH4-79.53 kJ/mol。 第二步是液体乙酸吸收乙烯酮生成醋酐。反应方程式为： CH2=C=O+CH3COOH(CH3CO)2O+62.8kJ/mol。 但在相同规模下，丙酮法和醋酸法比较，丙酮法需要较大的裂解炉、吸收塔和洗涤塔，并增加了循环丙酮-水的蒸馏分离等辅助设备，项目建设费用高。同时，丙酮法的生产成本也较高。 乙烯酮法相对乙醛氧化法和醋酸甲酯羰基化工艺来说，流程复杂，副反应多，能耗较大，利润较低。由于生产技术相当成熟，在国外早期建设的装置应用该法，在我国仍普遍应用。 1973年，Halcon科学开发集团公司取得了醋酸甲酯羰基化生产的醋酐的专利。1983年，该公司与美国Eastman-Kodak公司合作建成了第一套羰基合成醋酐生产装置。Celanese公司也拥有此技术。生产工艺如下：首先是甲醇和醋酸在硫酸催化剂作用下生成醋酸甲酯，反应压力为常压，反应温度为65-85，醋酸转化率约100%。然后，醋酸甲酯与甲醇和一氧化碳在碘甲烷和铑系催化剂或镍系催化剂(因铑系催化剂催化活性是镍系催化剂的10倍，因此工业上多采用铑系催化剂)存在下，进行羰基化反应生成醋酐，并联产醋酸。反应压力为2.55 MPa左右，反应温度为180左右。其醋酐/醋酸比可以根据需要进行调节。反应方程式为： CH3COOH+CH3OHCH3COOCH3+H2O； CH3COOCH3+CO (CH3CO)2O； CH3OH+COCH3COOH。 醋酸甲酯羰基合成法具有流程短、产品质量好、消耗低、三废排放少等优点，代表着醋酐生产技术的先进水平。目前，国外主要的醋酐供应厂均采用该工艺。液相工艺比气相工艺成熟。英国BP公司在Halcon合成醋酐和Monsanto羰基化制醋酸工艺的基础上，成功开发了甲醇羰基化联产醋酐-醋酸工艺，并于1987年实现工业化。 气相羰基合成法是Hoechst公司于1986年开发的，反应温度185-216，采用非均相负载催化剂。这种催化剂是将贵金属铑、铱、钯或铷载于二氧化硅、三氧化二铝、氧化镁、二氧化钛等载体上，其中铑表现出最高的活性。气相法的酯化反应与液相法是相同的，羰基化反应与液相羰基化也是相似的。不同之处在于：液相羰基化法在液相状态进行醋酸甲酯的羰基化反应；而气相羰基化法反应在气相中进行，气相工艺取消了从反应液中回收催化剂。气相工艺可降低铑的损失，铑是固定在载体上而不在可偶然被冲洗掉的溶液中。气相工艺在投资方面优于液相工艺，但其公用工程费用消耗较高。 2003年，江苏丹化集团、中科院和北京大学三家合作，建成国内第一套羰基化合成醋酐装置，装置规模为2万t/a醋酐(见图2(略)。该装置也可以调整生产醋酸甲酯，由兰州石化设计院承担工程总承包及设计，生产出的醋酐产品纯度达到99.5%以上，醋酸甲酯达到99.9%以上。每吨醋酐消耗定额为甲醇0.353 t，醋酸0.604t，CO为0.340t，催化剂0.44 z，蒸汽4.2 t，水147 t，电167kwh，仪表空气300m3。装置运行实践证明，我国自行研制的这套醋酐生产工艺是可靠的。羰基化合成醋酐工艺，反应器由酯化器和羰基化反应器构成，甲醇和醋酸在酯化器生成醋酸甲酯，醋酸甲酯在羰基化反应器内与CO合成醋酐。由于该工艺催化剂里有水，生成醋酐的-同时，还生成一部分醋酸。该工艺以生产醋酐为主时，主要原料为甲醇、CO和醋酸。另外，该工艺还可以直接用原料CO和甲醇在羰基化反应器内反应生成醋酸，无需经过酯化器。因此，该工艺可以根据市场需求进行醋酸、醋酸甲酯和醋酐的产品切换。 羰基化法最重要的技术是催化剂，中国科学院化学研究所经过多年研究开发并研制了国产催化剂多齿季基杂合型铑配合物催化剂。与美国孟山都开发的催化剂比较，该国产催化剂具有水含量少的优点。从江苏丹化集团的使用情况看，反应条件与国外催化剂基本相同(反应压力3-6MPa，温度160-200)，应用比较理想。 除了用铑系催化剂外，羰基合成醋酐工艺还可用其它金属催化剂。虽然铑系催化剂的催化活性和选择性最好，但存在着价格昂贵、资源短缺、回收费用高等缺点。因此，很多公司都将注意力转移到了非贵金属催化剂上，它们主要是I A-A、 B或 B的非贵重金属。其中，镍催化剂在反应条件的温和性以及催化性能等方面明显优于其它非贵金属，是一类最具开发前景的非贵金属催化剂。 乙烯酮法和羰基合成法是目前生产醋酐的常用的方法。从对比表1可以看出，乙烯酮法工艺流程相对复杂，产品质量较低，能耗相对，高，成本高，污染重，规模小。- 7 -