公开(公告)号：DE59704095D1

公开(公告)日：2001-08-30

申请号：DE59704095

申请日：1997-02-04

Applicant: BASF AG

Inventor： SCHMIDT WILLI ,  GEISENDOERFER DR ,  DOCKNER DR ,  HERBST DR ,  NESTLER DR ,  WECK ALEXANDER

IPC: C07B61/00 ,  C07C67/08 ,  C07C67/54 ,  B01J31/02 ,  C07C69/54

Abstract: In the continuous production of alkyl (meth)acrylates (AA) by reacting (meth)acrylic acid with 1-8 carbon (C) monohydric alkanols in homogeneous liquid phase, free from solvent, at elevated temperature and in the presence of an acid esterification catalyst; (a) (meth)acrylic acid, alkanol and catalyst are fed to a reaction zone; (b) during a residence time, the water formed is separated in a rectification unit (RU) III above the reaction zone; (c) the aqueous distillate is separated into an organic phase containing the alkanol and an aqueous phase; (d) the organic phase is recycled to RU III; and (e) the reaction mixture is discharged from the reaction zone and passed to another RU, where AA is separated by distillation. The novel features are that: (i) the molar ratio of (meth)acrylic acid and alkanol is 1:(0.75-2); (ii) the aqueous phase from RU III is partly recycled to RU III; (iii) the reaction mixture is passed to RU I, in which it is separated into a product (II) containing the catalyst and a product (I) containing AA, residual alkanol and residual (meth)acrylic acid; and (iv) (I) is passed to RU II, in which AA is separated from residual alkanol and residual (meth)acrylic acid and the alkanol and acid are recycled to the reaction zone. Preferably the alkanol is 2-ethylhexanol. The catalyst is para-toluenesulphonic acid (p-TSA) and/or other organic sulphonic acids, e.g. methane-, benzene- or dodecylbenzene-sulphonic acid, and/or sulphuric acid (H2SO4). The catalyst concentration in the reaction mixture is 0.1-10, especially 0.1-6 wt.% p-TSA in the reaction zone and 2.5-50 wt.% p-TSA in the sump or an equimolar amount of organic sulphonic acid and/or H2SO4. The reaction zone consists of a cascade of NOTLESS 2, especially 2-4 consecutive sections, especially reactors with circulating vapourisers. All rectification units are rectification columns.

公开(公告)号：DE59711330D1

公开(公告)日：2004-04-01

申请号：DE59711330

申请日：1997-08-18

Applicant: BASF AG

Inventor： HIEBER DR ,  EBEL DR ,  SCHROEDER DR ,  DOCKNER DR ,  GROENING DR ,  RUGE DR

IPC: C07D233/58 ,  B01J21/12 ,  B01J27/16 ,  C07D233/54 ,  C07D233/68 ,  C07D233/90 ,  C07D233/91 ,  C07D233/92 ,  C07D235/06 ,  C07D235/08

Abstract: Preparation of substituted imidazole derivatives of formula (I) comprises reaction of an imidazole of formula (II) with a compound of formula R4OR5 (III) at 200-550 degrees C in the presence of a catalyst containing oxides or phosphates of one or metals of the 2nd, 3rd and 4th main periods and the 4th transition period, optionally in the presence of phosphoric acid or phosphate esters. R1-R3 = H, halo, NO2, CN or 1-20C hydrocarbon (optionally mono- or poly-halogenated); or R1+R2 complete a 3-20C cyclic hydrocarbon optionally containing 1-3 heteroatoms from N, O or S (optionally mono- to poly-substituted by halo or 1-8C alkyl); R4 = 1-20C hydrocarbon (optionally mono- or poly-halogenated); R5 = R4 or H.

公开(公告)号：DE59606209D1

公开(公告)日：2001-01-18

申请号：DE59606209

申请日：1996-09-26

Applicant: BASF AG

Inventor： EXNER DR ,  BAUR DR ,  DOCKNER DR ,  POTTHOFF CHRISTIANE ,  DAMS DR

IPC: C07C67/08 ,  C07C67/54 ,  C07C69/54

Abstract: The continuous prodn. of alkyl(meth)acrylates (I) by the reaction of (meth)acrylic acid (II) and 1-8C monohydric alcohols (III) in homogeneous liq. phase at elevated temp. in the absence of solvent and in presence of an acid esterification catalyst (IV). The process comprises (a) feeding (II), (III) and (IV) continuously into a reaction zone (RZ), (b) removing (I) after a residence time in the form of an azeotrope contg. water or water and (III) in addn. to (I) at the top of a rectifier column (RC) mounted over the RZ, (c) separating the distillate into an organic phase contg. (I) and aq. phase(s) contg. water, (d) recycling part of the organic phase via the top of the column and opt. returning water to the RZ, (e) separating (I) from the rest of the organic phase and removing part of the reaction mixt. continuously from the RZ. The RZ consists of a cascade of at least two reactors in series, and the outflow from one reactor provides the input flow for the next reactor. Also claimed is an appts. for this process.