中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

63 records (took 0.021 seconds)

    34.
    发明专利
    未知

    公开(公告)号：DE59705933D1

    公开(公告)日：2002-02-07

    申请号：DE59705933

    申请日：1997-06-04

    Applicant: BASF AG

    Inventor： HAGEMEYER ALFRED DR ,  HEINEKE DANIEL DR ,  VOIT GUIDO DR ,  WITZEL TOM DR

    IPC: B01J23/18 ,  C07B61/00 ,  C07C245/08 ,  C07C291/08

    Abstract: A process for the reductive coupling of nitrobenzene (NB) to give azobenzene (AB) and azoxybenzene (AOB), comprises passing NB with gaseous, hydrogen-free reducing agent(s) (RA) at elevated temperature in the gas phase over a heterogeneous redox catalyst in its reduced or partly reduced form. The catalyst contains active metal(s) of Bi, V, Cr, Mn, Fe, Co, Pb, Mo, Ce, U, Sn, Sb, Cu, La, W, Nb, Pd, Pt, Ni and/or In, and the average oxidation state of the active metal before contact with NB and RA is at least 0.5 below the maximum oxidation state which is stable under the reaction conditions. Also claimed is (i) a similar process in which the NB is deoxygenated by passing over a redox catalyst as above in the absence of any free gaseous RA and in amounts such that the catalyst is not completely spent; and (ii) redox catalysts as above.

    39.
    发明专利
    未知

    公开(公告)号：DE19653093A1

    公开(公告)日：1998-06-25

    申请号：DE19653093

    申请日：1996-12-20

    Applicant: BASF AG

    Inventor： KRATZ DETLEF DR ,  STAMMER ACHIM DR ,  SCHULZ GERHARD DR ,  VOIT GUIDO DR

    IPC: C07B61/00 ,  C07C29/141 ,  C07C29/80 ,  C07C31/22 ,  C07C45/75 ,  C07C47/19 ,  C07C31/18 ,  C07C29/14 ,  C07C29/34

    Abstract: The invention relates to a method for producing polymethylol compounds of formula (I), in which R represents a further methylol group or an alkyl group with between 1 and 22 C atoms or an aryl or alkyl aryl group with between 6 and 22 C atoms, by condensating aldehydes with between 2 and 24 C atoms with formaldehyde, using tertiary amines as catalysts, with a view to obtaining compounds of formula (II), in which R has the meaning assigned to it above. The invention further relates to a process for hydrogenating polymethylol compounds by condensation in stages. For this, a) in a first (reaction) stage, the aldehydes with 2 or more C atoms are reacted with 2 to 8 times the molar quantity of formaldehyde in the presence of a tertiary amine as catalyst; b) in a second (separation) stage, either the reaction mixture is separated into a distillation residue containing primarily the compounds of formula (II) and a destillation flow containing primarily the compounds of unreacted or partly reacted starting materials which is fed back to the first stage, or the reaction mixture of the first stage is separated into an aqueous and an organic phase by means of a phase separation device and the organic phase fed back to the first stage, and c) in a third (post-reaction distillation) stage, the distillation residue of the second stage or the aqueous phase obtained by phase separation during the second stage is subjected to a catalytic and/or heat treatment, the compound of formula (III) which has not been fully methylolized is transformed into the corresponding compound of formula (II) and into the corresponding methylene compound of formula (IV), in which R' represents hydrogen or has the meaning assigned above to R, the reaction mixture obtained in this way is distilled, and the distillation overhead product, which contains a compound of formula (IV) and unreacted formaldehyde, is fed back to the first stage. Thereafter, the still bottom of this distillation process, which essentially contains the compound of formula (II), is hydrogenated in the known manner so as to obtain the corresponding end product of formula (I).

Patent Agency Ranking