53.
    发明专利
    未知

    公开(公告)号:ES2172958T3

    公开(公告)日:2002-10-01

    申请号:ES98967143

    申请日:1998-11-24

    Applicant: BASF AG

    Abstract: A process for continuous extraction of polyamide particles in an essentially vertical extraction column using an aqueous extractant comprises using an extraction column that is divided into two zones and performing an extraction with a recirculating 15-40% strength by weight aqueous epsi-caprolactam solution in the first zone and then with countercurrent water at a from 5 to 40° C. lower temperature in the second zone. The process provides for economical extraction of polyamides with a low level of monomers and oligomers.

    55.
    发明专利
    未知

    公开(公告)号:DE59803036D1

    公开(公告)日:2002-03-21

    申请号:DE59803036

    申请日:1998-11-24

    Applicant: BASF AG

    Abstract: A process for continuous extraction of polyamide particles in an essentially vertical extraction column using an aqueous extractant comprises using an extraction column that is divided into two zones and performing an extraction with a recirculating 15-40% strength by weight aqueous epsi-caprolactam solution in the first zone and then with countercurrent water at a from 5 to 40° C. lower temperature in the second zone. The process provides for economical extraction of polyamides with a low level of monomers and oligomers.

    56.
    发明专利
    未知

    公开(公告)号:BR0011402A

    公开(公告)日:2002-03-05

    申请号:BR0011402

    申请日:2000-06-05

    Applicant: BASF AG

    Abstract: A process for producing polyamides by reacting at least one lactam and optionally further polyamide-forming monomers with aqueous monomer and oligomer extracts obtained during the extraction with water of the polymer product obtained in the production of polyamides, the water content of the reaction mixture being in the range from 0.5 to 13% by weight comprises conducting the reaction in the presence of metal oxides, beta-zeolites, sheet-silicates or silica gels, which may be doped, as heterogeneous catalysts, the heterogeneous catalysts being used in the form which permits mechanical removal from the reaction mixture and are removed from the reaction mixture in the course of the polymerization or after it has ended.

    DEVICE FOR DRYING AND THERMALLY TREATING GRANULATES WITH AN INERT GAS STREAM

    公开(公告)号:CA2394013A1

    公开(公告)日:2001-06-07

    申请号:CA2394013

    申请日:2000-11-29

    Applicant: BASF AG

    Abstract: The invention relates to a device (1) for drying and thermally treating granulates with an inert gas stream. Said device has a cuboidal base body (2 ) comprising an inlet (3) for the granulate in the upper part and an outlet (4 ) in the lower part. Said device has an inlet (5) on a side surface and an outlet (6) on the opposite side surfaces of the cuboidal base body (2) for t he inert gas stream. Said device also comprises a distribution and retaining device (7, 8) in the region of the inlet (5) and outlet (6) of the inert gas stream which substantially extend over the total vertical cross-section of t he cuboidal base body (2).

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