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1、<p>  吉林化工學(xué)院成人教育學(xué)院</p><p><b>  畢業(yè)設(shè)計(jì)外文翻譯</b></p><p>  8000噸/年醋酐裝置精餾工段工藝設(shè)計(jì)</p><p><b>  吉林化工學(xué)院</b></p><p>  JilinInstituteofChemicalTechnology

2、</p><p>  Acetic anhydride production process</p><p>  Acetic anhydride is a colorless volatile, with a strong irritating smell and corrosiveness liquid. Name of acetic anhydride, molecular form

3、ula 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

4、ignition temperature of 388.9 DEG c.. Soluble in cold water, in water is decomposed into acetic acid, ethyl acetate and ethanol production. S</p><p>  Acetic anhydride is the country to encourage the develop

5、ment 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

6、 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, ma

7、nagement must </p><p>  Industrialization of acetic anhydride production process has three kinds: the oxidation of acetaldehyde, ethylene ketone and methyl acetate carbonylation.</p><p>  Acetal

8、dehyde 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

9、 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 gen

10、erated peroxy acetic acid, acetic acid and acetaldehyd</p><p>  CH3CHO+O2 - CH3COOOH;</p><p>  CH3COOOH+CH3CHO CH3COOOCH ( OH )</p><p>  CH3 ( single peroxy acetic ester );</p>

11、;<p>  CH3COOOCH ( OH ) CH3 - ( CH3CO ) 2O+H2O;</p><p>  CH3COOOCH ( OH CH3 2CH3COOH ).</p><p>  Acetaldehyde acetic anhydride consumption per ton of 1.165 T, 2300 m3 standard air. Acetal

12、dehyde 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 aceta

13、te and vinyl ketone method alternative. China Shanghai Chemical Reagent Factory of this device has been in a state of production.</p><p>  Vinyl ketone law in accordance with the different materials can be d

14、ivided into: acetic acid and acetone method.</p><p>  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

15、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%,

16、 on vinyl ketone selectivity (corporeal quantity meter ) is about 90%-95%. Reaction equation:</p><p>  CH3COOH CH2 = C = O+H2O+147 kJ / mol.</p><p>  The second step is to absorb liquid acetic a

17、cid ethylene ketone anhydride generating, by distillation and purification to obtain the product of acetic anhydride, vinyl ketone conversion rate of about 100%. Reaction equation:</p><p>  CH3COOH+CH2 = C =

18、 O ( CH3CO ) 2O+62.8kJ / mol.</p><p>  The production process is a German Wacher chemical company to develop a success, and in 1936 achieved industrialization. Two existing production process:</p><

19、;p>  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 recov

20、ery.</p><p>  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

21、 for acetic acid cracking rate, 1.22 T, 75%, the yield of synthesis of 96%.</p><p>  The production process is as follows:</p><p>  The first step is to acetone in 700-800 C, atmospheric pressur

22、e, no catalyst under the conditions of the cleavage reaction. Reaction equation:</p><p>  CH3COCH3 CH2 = C = O+CH4-79.53 kJ / mol.</p><p>  The second step is to absorb the liquid acetic acid et

23、hylene ketone anhydride generating. Reaction equation:</p><p>  CH2 = C = O+CH3COOH ( CH3CO ) 2O+62.8kJ / mol.</p><p>  But in the same scale, acetone and acetic acid, acetone method requires la

24、rger 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 p

25、roduction cost is also higher acetone method.</p><p>  Ketene process relative acetaldehyde oxidation and carbonylation of methyl acetate to the process, the process is complex, a lot of side reactions, high

26、 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.</p><p>  In 1973, Halcon Scientifi

27、c 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 carbonyla

28、tion 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 cataly

29、st to generate methyl acetate, the </p><p>  CH3COOH+CH3OH - CH3COOCH3+H2O;</p><p>  CH3COOCH3+CO ( CH3CO ) 2O;</p><p>  CH3OH+CO - CH3COOH.</p><p>  Methyl acetate car

30、bonylation 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 a

31、re 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,

32、the successful development of the carbonyl</p><p>  Gas phase carbonylation of Hoechst company in 1986 developed, reaction temperature, 185-216 C, by heterogeneous supported catalysts. The catalyst is a prec

33、ious 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

34、liquid phase method are the same, and liquid phase carbonylation carbonylation are similar. The difference is: the liquid pha</p><p>  In 2003, Dan group of Jiangsu, Chinese Academy of Sciences and Beijing U

35、niversity 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

36、 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 an</p>

37、<p>  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 t

38、he 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, VII

39、I non-noble metals. Among them, nickel catalyst in the reaction conditi</p><p>  Vinyl ketone and carbonyl synthesis process is the production of acetic anhydride used method. From the contrast can be seen i

40、n Table 1, ketene process is relatively complex, the product quality is low, the energy consumption is relatively high, high cost, pollution, heavy, small scale. </p><p><b>  醋酐生產(chǎn)工藝</b></p>

41、<p>  醋酐為無色易揮發(fā),具有強(qiáng)烈刺激性氣味和腐蝕性液體。學(xué)名乙酸酐,分子式為C4H6O3,閃點(diǎn)64.4℃。密度1.082 0g/cm3。熔點(diǎn)-74.13℃。沸點(diǎn)138.63℃。折射率nD 1.390。20℃粘度0.91 mPa?s。自燃點(diǎn)388.9℃。溶于冷水,在熱水中分解成醋酸,與乙醇生成乙酸乙酯。溶于氯仿、乙醚和苯。有毒,對(duì)眼及粘膜具有強(qiáng)烈的刺激性,質(zhì)量濃度為0.36 mg/m3時(shí)即對(duì)眼有刺激;0.18mg/m3

42、時(shí),就能改變?nèi)说哪X電圖象,還能引起細(xì)胞組織蛋白質(zhì)變質(zhì)。其蒸氣刺激性更強(qiáng),極易燒傷皮膚及眼睛,如經(jīng)常接觸會(huì)引起皮炎和慢性結(jié)膜炎。對(duì)大鼠經(jīng)口LD50為1780 mg/kg。當(dāng)濺及或粘附于皮膚時(shí),要立即用清水或2%蘇打水沖洗,全身中毒時(shí)應(yīng)及時(shí)就醫(yī)診治??諝庵凶罡呷菰S體積分?jǐn)?shù)5μL/L。 </p><p>  醋酐是國家鼓勵(lì)發(fā)展的基本有機(jī)化工原料,主要用于生產(chǎn)醋酸纖維素,其中二醋酸纖維素用于制造香煙過濾嘴和塑料,三醋酸纖

43、維素是制造高級(jí)感光膠片的材料,還廣泛用于醫(yī)藥、染料、農(nóng)藥、軍工、香料、金屬拋光等行業(yè)。</p><p>  醋酐是“易制毒”產(chǎn)品,醋酐的生產(chǎn)、經(jīng)營都要依法在公安機(jī)關(guān)備案取證,企業(yè)賣出的每一批商品都要進(jìn)行詳細(xì)的備案登記,并到公安機(jī)關(guān)備案。依據(jù)法律規(guī)定,賣給無證單位200 kg醋酐,將被判處3年有期徒刑。</p><p>  工業(yè)化的醋酐生產(chǎn)工藝有三種:乙醛氧化法、乙烯酮法和醋酸甲酯羰基化。&

44、lt;/p><p>  乙醛氧化法技術(shù)來源為加拿大Sha Winigan化學(xué)公司。生產(chǎn)工藝如下:乙醛和氧在60℃、101 kPa或70℃、600-700kPa條件下進(jìn)行氧化反應(yīng),用氧氣或空氣作氧化劑,以醋酸乙酯為溶劑,醋酸鈷為催化劑,醋酸銅為促進(jìn)劑。乙醛與氧氣(過量約1%-2%)反應(yīng)首先生成過氧醋酸,過氧醋酸再與乙醛反應(yīng)生成醋酐和醋酸。在此條件下,乙醛轉(zhuǎn)化率為95%,醋酐及醋酸產(chǎn)率的質(zhì)量比為56:44。醋酐的總收率為

45、70%-75%。通過改變工藝條件,可以提高醋酐的產(chǎn)率。反應(yīng)方程式為:</p><p>  CH3CHO+O2→CH3COOOH;</p><p>  CH3COOOH+CH3CHO→CH3COOOCH(OH)</p><p>  CH3(單過氧醋酸酯);</p><p>  CH3COOOCH(OH)CH3→(CH3CO)2O+H2O;<

46、;/p><p>  CH3COOOCH(OH)CH3→2CH3COOH。</p><p>  每噸醋酐消耗乙醛1.165 t,標(biāo)準(zhǔn)狀態(tài)空氣2300 m3。乙醛氧化法流程簡(jiǎn)單,工藝成熟,但腐蝕嚴(yán)重,消耗較高,已逐漸被淘汰。在國外已被醋酸甲酯羰基化和乙烯酮法所替代。我國上?;瘜W(xué)試劑總廠這種裝置已經(jīng)處于停產(chǎn)狀態(tài)。</p><p>  乙烯酮法按照原料不同又可以分為:醋酸法和丙

47、酮法。</p><p>  醋酸法技術(shù)來源為德國Wacher化學(xué)公司。生產(chǎn)工藝如下:第一步,醋酸在700-750℃、10-20kPa的壓力及0.2%-0.3%磷酸三乙酯(按醋酸質(zhì)量計(jì))作催化劑的條件下,裂解脫水制成乙烯酮,醋酸轉(zhuǎn)化率約為85%-90%,對(duì)乙烯酮的選擇性(物質(zhì)的量計(jì))約為90%-95%。反應(yīng)方程式為:</p><p>  CH3COOH→CH2=C=O+H2O+147 kJ/

48、mol。</p><p>  第二步是液體乙酸吸收乙烯酮生成醋酐,經(jīng)精餾提純制得成品醋酐,乙烯酮的轉(zhuǎn)化率約100%。反應(yīng)方程式為:</p><p>  CH3COOH+CH2=C=O→(CH3CO)2O+62.8kJ/mol。</p><p>  該生產(chǎn)工藝是德國Wacher化學(xué)公司開發(fā)成功的,并于1936年實(shí)現(xiàn)工業(yè)化?,F(xiàn)有兩種生產(chǎn)流程:</p>&l

49、t;p>  其一,為塔式流程。用4個(gè)填料塔進(jìn)行合成與分離。每噸醋酐的消耗定額為,醋酸1.35t,催化劑1.5-2kg,氨0.7-1.0kg,回收醋酸100-160kg。</p><p>  其二,為液環(huán)泵流程。以液環(huán)泵為反應(yīng)及吸收設(shè)備。該流程十分簡(jiǎn)單,正在取代塔式流程。每噸產(chǎn)品的消耗定額為,醋酸1.22 t,裂解率75%,合成收率96%。</p><p><b>  生產(chǎn)工

50、藝如下:</b></p><p>  第一步是丙酮在700-800℃、常壓、沒有催化劑的條件下進(jìn)行裂解反應(yīng)。反應(yīng)方程式為:</p><p>  CH3COCH3→CH2=C=O+CH4-79.53 kJ/mol。</p><p>  第二步是液體乙酸吸收乙烯酮生成醋酐。反應(yīng)方程式為:</p><p>  CH2=C=O+CH3CO

51、OH→(CH3CO)2O+62.8kJ/mol。</p><p>  但在相同規(guī)模下,丙酮法和醋酸法比較,丙酮法需要較大的裂解爐、吸收塔和洗滌塔,并增加了循環(huán)丙酮-水的蒸餾分離等輔助設(shè)備,項(xiàng)目建設(shè)費(fèi)用高。同時(shí),丙酮法的生產(chǎn)成本也較高。</p><p>  乙烯酮法相對(duì)乙醛氧化法和醋酸甲酯羰基化工藝來說,流程復(fù)雜,副反應(yīng)多,能耗較大,利潤(rùn)較低。由于生產(chǎn)技術(shù)相當(dāng)成熟,在國外早期建設(shè)的裝置應(yīng)用該

52、法,在我國仍普遍應(yīng)用。</p><p>  1973年,Halcon科學(xué)開發(fā)集團(tuán)公司取得了醋酸甲酯羰基化生產(chǎn)的醋酐的專利。1983年,該公司與美國Eastman-Kodak公司合作建成了第一套羰基合成醋酐生產(chǎn)裝置。Celanese公司也擁有此技術(shù)。生產(chǎn)工藝如下:首先是甲醇和醋酸在硫酸催化劑作用下生成醋酸甲酯,反應(yīng)壓力為常壓,反應(yīng)溫度為65-85℃,醋酸轉(zhuǎn)化率約100%。然后,醋酸甲酯與甲醇和一氧化碳在碘甲烷和銠系

53、催化劑或鎳系催化劑(因銠系催化劑催化活性是鎳系催化劑的10倍,因此工業(yè)上多采用銠系催化劑)存在下,進(jìn)行羰基化反應(yīng)生成醋酐,并聯(lián)產(chǎn)醋酸。反應(yīng)壓力為2.55 MPa左右,反應(yīng)溫度為180℃左右。其醋酐/醋酸比可以根據(jù)需要進(jìn)行調(diào)節(jié)。反應(yīng)方程式為:</p><p>  CH3COOH+CH3OH→CH3COOCH3+H2O;</p><p>  CH3COOCH3+CO (CH3CO)2O;<

54、;/p><p>  CH3OH+CO→CH3COOH。</p><p>  醋酸甲酯羰基合成法具有流程短、產(chǎn)品質(zhì)量好、消耗低、三廢排放少等優(yōu)點(diǎn),代表著醋酐生產(chǎn)技術(shù)的先進(jìn)水平。目前,國外主要的醋酐供應(yīng)廠均采用該工藝。液相工藝比氣相工藝成熟。英國BP公司在Halcon合成醋酐和Monsanto羰基化制醋酸工藝的基礎(chǔ)上,成功開發(fā)了甲醇羰基化聯(lián)產(chǎn)醋酐-醋酸工藝,并于1987年實(shí)現(xiàn)工業(yè)化。</p&

55、gt;<p>  氣相羰基合成法是Hoechst公司于1986年開發(fā)的,反應(yīng)溫度185-216℃,采用非均相負(fù)載催化劑。這種催化劑是將貴金屬銠、銥、鈀或銣載于二氧化硅、三氧化二鋁、氧化鎂、二氧化鈦等載體上,其中銠表現(xiàn)出最高的活性。氣相法的酯化反應(yīng)與液相法是相同的,羰基化反應(yīng)與液相羰基化也是相似的。不同之處在于:液相羰基化法在液相狀態(tài)進(jìn)行醋酸甲酯的羰基化反應(yīng);而氣相羰基化法反應(yīng)在氣相中進(jìn)行,氣相工藝取消了從反應(yīng)液中回收催化劑

56、。氣相工藝可降低銠的損失,銠是固定在載體上而不在可偶然被沖洗掉的溶液中。氣相工藝在投資方面優(yōu)于液相工藝,但其公用工程費(fèi)用消耗較高。</p><p>  2003年,江蘇丹化集團(tuán)、中科院和北京大學(xué)三家合作,建成國內(nèi)第一套羰基化合成醋酐裝置,裝置規(guī)模為2萬t/a醋酐(見圖2(略))。該裝置也可以調(diào)整生產(chǎn)醋酸甲酯,由蘭州石化設(shè)計(jì)院承擔(dān)工程總承包及設(shè)計(jì),生產(chǎn)出的醋酐產(chǎn)品純度達(dá)到99.5%以上,醋酸甲酯達(dá)到99.9%以上。

57、每噸醋酐消耗定額為甲醇0.353 t,醋酸0.604t,CO為0.340t,催化劑0.44 z,蒸汽4.2 t,水147 t,電167kwh,儀表空氣300m3。裝置運(yùn)行實(shí)踐證明,我國自行研制的這套醋酐生產(chǎn)工藝是可靠的。羰基化合成醋酐工藝,反應(yīng)器由酯化器和羰基化反應(yīng)器構(gòu)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應(yīng)器內(nèi)與CO合成醋酐。由于該工藝催化劑里有水,生成醋酐的-同時(shí),還生成一部分醋酸。該工藝以生產(chǎn)醋酐為主時(shí),主要原料為

58、甲醇、CO和醋酸。另外,該工藝還可以直接用原料CO和甲醇在羰基化反應(yīng)器內(nèi)反應(yīng)生成醋酸,無需經(jīng)過酯化器。因此,該工藝可以根據(jù)市場(chǎng)需求進(jìn)行醋酸、醋酸甲酯和醋酐的產(chǎn)品切換。</p><p>  羰基化法最重要的技術(shù)是催化劑,中國科學(xué)院化學(xué)研究所經(jīng)過多年研究開發(fā)并研制了國產(chǎn)催化劑——多齒季基雜合型銠配合物催化劑。與美國孟山都開發(fā)的催化劑比較,該國產(chǎn)催化劑具有水含量少的優(yōu)點(diǎn)。從江蘇丹化集團(tuán)的使用情況看,反應(yīng)條件與國外催化劑

59、基本相同(反應(yīng)壓力3-6MPa,溫度160-200℃),應(yīng)用比較理想。</p><p>  除了用銠系催化劑外,羰基合成醋酐工藝還可用其它金屬催化劑。雖然銠系催化劑的催化活性和選擇性最好,但存在著價(jià)格昂貴、資源短缺、回收費(fèi)用高等缺點(diǎn)。因此,很多公司都將注意力轉(zhuǎn)移到了非貴金屬催化劑上,它們主要是I A-ⅢA、Ⅵ B或Ⅷ B的非貴重金屬。其中,鎳催化劑在反應(yīng)條件的溫和性以及催化性能等方面明顯優(yōu)于其它非貴金屬,是一類最

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