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تكفووون يامهندسين .. أريد المساعدة مرة أخرى !!!!!!

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    Eng_Meshal
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    تكفووون يامهندسين .. أريد المساعدة مرة أخرى !!!!!!

    جزاك الله خيرا يا أخوي softchem على ما قدمت _ و رحم الله والديك _ ولكنني أريد كل ماذكرته من detailes وخاصة PFD عن مادة " Acrylonitrile " بالضبط , فما قدمته كان عن Acrylic Acid وهذه إحدى المواد المستخلصة من " Acrylonitrile" .......
    وحتى تصير أسهل , التفاعل كالتالي :


    2CH3-CH=CH2 + 2NH3 + 3O22CH2=CH-C≡N + 6H2O

    ويتم ذلك عن طريق أكسدة البروبيلين و الأمونيا
    The most industrial acrylonitrile is produced through the( Sohio process) , the catalytic ammoxidation of propylene

  2. [2]
    وليد محمود مغاته
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    أخي العزيز زور هذه المواقع وانتظر مني المزيد ولن ان شاء الله بعد يومين
    www.scorecard.org/chemical-profiles/summary.tcl?edf_substance_id=107-13-1
    http://www.pci-acrylo.com/

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  3. [3]
    muslimonline7
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    السلام عليكم ورحمة الله وبركاته

    إليك بعض المعلوامات التي ارجو ان تفيدك عن ال acrylonitrile

    1. [LEFT]Introduction

    In 1893, the French chemist, Ch. Moureau, first prepared acrylonitrile [107-13-1], acrylic acid nitrile, propene nitrile, vinyl cyanide, CH2=CH-CºN, Mr 53.06, by dehydrating either acrylamide or ethylene cyanohydrin with phosphorus pentoxide [1]. However, no significant technical or commercial applications were discovered for acrylonitrile until the late 1930s.

    Shortly before the Second World War, I. G. Farbenindustrie introduced a synthetic rubber, Buna N, based on a copolymer of butadiene and acrylonitrile. This synthetic rubber was highly resistant to swelling in gasoline, oils, and other nonpolar solvents. At about the same time research began in the United States on similar copolymers termed GR-A, NBR, or nitrile rubber. Projects concerning acrylonitrile-containing polymers received special support during the Second World War because of obvious strategic importance, thus establishing acrylonitrile as a monomer with commercial significance.
    Since that time the dramatic increase in the demand for acrylonitrile has been attributed not to nitrile rubber but largely to acrylic fibers first introduced commercially in 1950 by Du Pont under the trademark Orlon. In addition, acrylonitrile is used in resins, thermoplastics, elastomers, and as an intermediate for organic synthesis, most notably for producing adiponitrile and acrylamide.

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    muslimonline7
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    4. Production [20, Chap. 1 – 7], [27], [28]

    Today nearly all acrylonitrile is produced by ammoxidation of propene [115-07-1]. Although the first report of the preparation of acrylonitrile from propene occurred in a patent by the Allied Chemical and Dye Corporation in 1947 [29], it was a decade later when Standard Oil of Ohio (Sohio) developed the first commercially viable catalyst for this process [30]. Today, all of the United States capacity and approximately 90 % of the world capacity for acrylonitrile is based on the Sohio process.

    Sohio Process [31], [32]. In the Sohio process (Fig. 1) propene, oxygen (as air), and ammonia are catalytically converted directly to acrylonitrile using a fluidized-bed reactor operated at temperatures of 400 – 500 °C and gauge pressures of 30 – 200 kPa (0.3 – 2 bar):





    Figure 1. Simplified diagram of the Sohio acrylonitrile process

    a) Fluidized-bed reactor; b) Absorber column; c) Extractive distillation column; d) Acetonitrile stripping column; e) Lights fractionation column; f) Product column
    [Full View]


    Complex mechanisms for this reaction have been described [33-35].

    Approximately stoichometric amounts of the starting materials are passed through the reactor with residence times of a few seconds. The process is highly selective, requiring no recycling to produce high acrylonitrile yields of approximately 0.8 – 0.9 kg from 1 kg of propene.Acetonitrile [75-05-8] (0.02 – 0.11 kg) and hydrogen cyanide [74-90-8] (HCN, 0.15 – 0.20 kg) are the principal byproducts (from 1 kg propene). The heat of reaction can be recovered as high-pressure steam.

    The catalyst used in the early Sohio process was a bismuth – phosphomolybdate combination. Since that time there has been a continuous search for alternatives and for superior performance, resulting in patents by more than 30 companies. Sohio introduced Catalyst 21 (antimony – uranium) in 1967, Catalyst 41 (ferrobismuth – phosphomolybdate) in 1972, and Catalyst 49 (undisclosed) in 1978. All of these changes were aimed at improved efficiency and reduction in byproducts.

    The reactor effluent is cooled and scrubbed with water in a countercurrent absorber. The off-gas, consisting primarily of nitrogen, is vented. The reaction products remain in the aqueous phase. Acetonitrile is removed by extractive distillation. Crude acrylonitrile and hydrogen cyanide are distilled overhead while water and acetonitrile are removed from the bottom of the columns. In subsequent distillations, hydrogen cyanide is separated from wet acrylonitrile, the water ******* of the product is then reduced, and finally, nonvolatile impurities are removed.

    The major byproducts of this process, hydrogen cyanide and acetonitrile, normally are incinerated as their supply often exceeds demand. Unused ammonia can be recovered as ammonium sulfate and then disposed of, but it commonly is vented to the atmosphere. Aqueous wastes containing cyanides, sulfates, and various organic byproducts must be disposed of by incineration or deepwell injection or be pretreated for subsequent biological waste treatment.

    Four companies, American Cyanamid, Du Pont, Monsanto, and Sohio (formerly Vistron Corp.) produce acrylonitrile in the United States via the Sohio process, with a total operating capacity of 9.5 × 105 t/a in 1980.

    Other Ammoxidation Processes [36]. Others who manufacture acrylonitrile by ammoxidation of propene include Distillers/Ugine, Societa Nazionale Metandotti (SNAM), Montedison-UOP, and Chemie Linz. All use different catalyst systems and, with the exception of Montedison-UOP, fixed-bed reactors.

    Production from Ethylene Cyanohydrin. Germany (I.G. Farben, Leverkusen) [37] and the United States (American Cyanamid) first produced acrylonitrile on an industrial scale in the early 1940s. These processes were based on the catalytic dehydration of ethylene cyanohydrin [38], [39]. Ethylene cyanohydrin was produced from ethylene oxide and aqueous hydrocyanic acid at 60 °C in the presence of a basic catalyst.The intermediate was then dehydrated in the liquid phase at 200 °C in the presence of magnesium carbonate and alkaline or alkaline earth salts of formic acid.





    An advantage of this process was that it generated few impurities; however, it was not economically competitive. American Cyanamid and Union Carbide closed plants based on this technology in the mid-1960s.

    Production from Acetylene and Hydrocyanic Acid. Before the development of the propene ammoxidation process, a major industrial route to acrylonitrile involved the catalytic addition of hydrocyanic acid to acetylene [27].





    Although a vapor-phase reaction has been reported, the commerical reaction usually was carried out at 80 °C in dilute hydrochloric acid containing cuprous chloride. Unreacted acetylene was recycled. The yield from this reaction was good; however, the raw materials were relatively expensive, some undesirable impurities, divinylacetylene and methyl vinyl ketone, were difficult to remove, and the catalyst required frequent regeneration. Du Pont, American Cyanamid, and Monsanto employed this process until about 1970.

    Other Routes to Acrylonitrile. Several other routes to acrylonitrile include nitrosation of propene [40], [41], ammonation of propionaldehyde [42], dehydrogenation of propionitrile [43], [44], and the reaction of hydrogen cyanide and acetaldehyde [45]. None of these processes has achieved the commercial status of those described previously.

    Future Processes. Several other chemicals have been studied as possible alternative precursors to acrylonitrile. Ethylene, propane, and butane react with ammonia at high temperatures (750 – 1000 °C) to yield acrylonitrile [46]. Monsanto, Power Gas, and ICI [47] have developed catalytic ammoxidation processes based on propane. Propane is of particular interest because of a cost advantage over propene. However, this price difference is not likely to be great enough in the near future to dictate change. High conversions to acrylonitrile also have been obtained on a laboratory scale from ethylene, hydrogen cyanide, and oxygen using a palladium-based catalyst [48].

    See Chapter Toxicology and Occupational Health for special precautions and regulations concerning the production of acrylonitrile.

    Figure 1. Simplified diagram of the Sohio acrylonitrile process

    a) Fluidized-bed reactor; b) Absorber column; c) Extractive distillation column; d) Acetonitrile stripping column; e) Lights fractionation column; f) Product column






    Ullmann's Encyclopedia of Industrial Chemistry
    Published by Wiley-VCH Verlag GmbH & Co. KGaA

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  5. [5]
    muslimonline7
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    السلام عليكم ورحمة الله وبركاته

    مرفق مع ذلك الرد صورة ضوئية من كتاب kirk-othmer encyclopedia

    يتحدث عن الجزء الخاص بال acrylonitrile

    ارجو ان يحوز اهتمامك

    وارجوك ان تخبرني ان كان ذلك ما تريد وتبحث عنه ام لا

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  6. [6]
    muslimonline7
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    السلام عليكم ورحمة الله وبركاته

    مرفق مع تلك الرسالة مقالة من ullmann's encyclopedia

    عن ال acrylonitrile

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