Method for producing phthalic anhydride

    公开(公告)号:AU1214402A

    公开(公告)日:2002-03-04

    申请号:AU1214402

    申请日:2001-08-20

    Applicant: BASF AG

    Abstract: A process for preparing phthalic anhydride by gas-phase oxidation of xylene, naphthalene or mixtures thereof over two different fixed-bed catalysts arranged in zones in a shell-and-tube reactor which is thermostated by means of a heat transfer medium is carried out so that the maximum temperature in the second catalyst zone in the flow direction is at least 52° C. lower than the maximum temperature in the first catalyst zone.The process of the present invention makes it possible to prepare phthalic anhydride in high yields under conditions relevant to industrial practice.

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    公开(公告)号:DE59706018D1

    公开(公告)日:2002-02-21

    申请号:DE59706018

    申请日:1997-07-07

    Applicant: BASF AG

    Abstract: A process for preparing caprolactam by cyclization of 6-aminocapronitrile in the presence of water at elevated temperature and in the presence or absence of a catalyst and a solvent, comprises a) removing from the cyclization reaction effluent ("reaction effluent I") caprolactam and all components boiling higher than caprolactam ("high boilers"), b) treating the high boilers of stage a) with phosphoric acid and/or polyphosphoric acid at from 200 to 350 DEG C. to obtain a reaction effluent II, and c) removing caprolactam formed and any 6-aminocapronitrile from reaction effluent II of stage b) to obtain separation from unconverted high boilers and acid used.

    123.
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    公开(公告)号:ID30506A

    公开(公告)日:2001-12-13

    申请号:ID20010419

    申请日:1999-08-17

    Applicant: BASF AG

    Abstract: A process for the coproduction of 6-aminocapronitrile and hexamethylenediamine starting from adiponitrile bya) hydrogenating adiponitrile in the presence of a catalyst comprising an element of the eighth transition group as catalytically active component, to obtain a mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers,b) distillatively removing hexamethylenediamine from the mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, and eithercl) distillatively removing 6-aminocapronitrile, and thend1) distillatively removing adiponitrile, orc2) simultaneously distillatively removing 6-aminocapronitrile and adiponitrile into separate fractionsis characterized by base of column temperatures below 185° C. in steps d1) or c2).

    124.
    发明专利
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    公开(公告)号:ID30503A

    公开(公告)日:2001-12-13

    申请号:ID20010474

    申请日:1999-08-17

    Applicant: BASF AG

    Abstract: A process for catalytic hydrogenation of adiponitrile to hexamethylenediamine at elevated temperature and elevated pressure in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent comprisesa) hydrogenating adiponitrile at from 70 to 220° C. and from 100 to 400 bar in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent to obtain a mixture comprising adiponitrile,6-aminocapronitrile, hexamethylenediamine and high boilers until the sum total of the 6-aminocapronitrile concentration and the adiponitrile concentration is within the range from 1 to 50% by weight, based on the ammonia-free hydrogenation mixture,b) removing ammonia from the hydrogenation effluent,c) removing hexamethylenediamine from the remaining mixture,d) separating 6-aminocapronitrile and adiponitrile from high boilers individually or together, ande) returning 6-aminocapronitrile, adiponitrile or mixtures thereof into step a).

    125.
    发明专利
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    公开(公告)号:DE59702349D1

    公开(公告)日:2001-10-31

    申请号:DE59702349

    申请日:1997-04-03

    Applicant: BASF AG

    Abstract: A process for the coproduction of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) by treatment of adiponitrile (ADN) with hydrogen in the presence of a nickel-containing catalyst at temperatures not below room temperature and elevated hydrogen partial pressure in the presence or absence of a solvent comprises, after the conversion based on ADN and/or the selectivity based on ACN has or have dropped below a defined value (a) interrupting the treatment of ADN with hydrogen by stopping the feed of ADN and of the solvent, if used, (b) treating the catalyst at from 150 DEG to 400 DEG C. with hydrogen using a hydrogen pressure within the range from 0.1 to 30 MPa and a treatment time within the range from 2 to 48 h, and (c) then continuing the hydrogenation of ADN with the treated catalyst of stage (b).

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