53.
    发明专利
    未知

    公开(公告)号:BR0113303A

    公开(公告)日:2003-12-30

    申请号:BR0113303

    申请日:2001-08-16

    Applicant: BASF AG

    Abstract: Described is a process for the preparation of a particulate tetrahydro-3,5-dimethyl-1,3,5-thiadiazine-2-thione product by combining a first aqueous solution comprising methylammonium N-methyldithiocarbamate with a second aqueous solution comprising formaldehyde, followed by separation and drying of the resulting solid, which comprises combining the first and the second aqueous solutions in such a way that the ratio between the concentrations of dithiocarbamate functions and of formaldehyde is essentially constant in the reaction mixture over time during the duration of the reaction.

    METHOD FOR THE SIMULTANEOUS PRODUCTION OF TETRAHYDROFURANS AND PYRROLIDONES

    公开(公告)号:AU2003227027A1

    公开(公告)日:2003-09-16

    申请号:AU2003227027

    申请日:2003-02-28

    Applicant: BASF AG

    Abstract: A process for coproducing alkyl-substituted or unsubstituted THF and pyrrolidones by catalytically hydrogenating C 4 -dicarboxylic acids and/or derivatives thereof in the gas phase in the presence of copper catalysts and reacting GBL with ammonia or primary amines to give pyrrolidones comprises a) hydrogenating C 4 -dicarboxylic acids and/or derivatives thereof in the gas phase at from 200 to 300° C., from 0.1 to 100 bar, catalyst hourly space velocities of from 0.01 to 1 kg of reactant/l of catalyst*hour and reactant/hydrogen molar ratios of from 20 to 800 in the presence of catalysts comprising copper, aluminum and/or zinc to give mixtures of THF and GBL, b) separating the hydrogenation effluent obtained by distillation into a THF/water mixture as the top product and a GBL-containing bottom product, c) separating the THF/water mixture from step b) in a distillation facility consisting of three columns by withdrawing water from the bottom of the first column, recycling water-containing THF from the second into the first column, passing a side stream of the first into the second column, recycling the bottom product of the third column into the first column and withdrawing a distillate at the top of the first column, wherein a side stream of the second column is passed into the third column and the pure THF is obtained as the top product of the third column, d) recovering GBL from the GBL-containing bottom product from step b) by distillation and e) reacting the GBL obtained with ammonia or amines to give corresponding pyrrolidones.

    55.
    发明专利
    未知

    公开(公告)号:DE10209632A1

    公开(公告)日:2003-09-11

    申请号:DE10209632

    申请日:2002-03-02

    Applicant: BASF AG

    Abstract: Crude water-containing tetrahydrofuran is purified by passing the crude tetrahydrofuran through three distillation columns, withdrawing water from the bottom of the first column, recycling water-containing tetrahydrofuran from the top of the second column into the first column, passing a sidestream of the first column into the second column, recycling the bottom product of the third column into the first column, and withdrawing a distillate at the top of the first column. Additionally, a sidestream of the second column is passed into the third column and the purified tetrahydrofuran is recovered as the top product of the third column.

    56.
    发明专利
    未知

    公开(公告)号:AT243722T

    公开(公告)日:2003-07-15

    申请号:AT99917985

    申请日:1999-04-15

    Applicant: BASF AG

    Abstract: The present invention relates to a process for preparing hydroxyl-containing polymers, in particular for preparing polytetrahydrofuran with terminal hydroxyl groups, from the corresponding acyloxy-containing polymers by transesterification with alcohols in the presence of an alkali metal- or alkaline earth metal-containing catalyst, which entails the appropriate acyloxy-containing polymer being introduced together with the alcohol and the catalyst into a first prereactor (I) and converted therein at least partly to the hydroxyl-containing polymer, and the reaction solution being fed into the upper zone (IIa) of a distillation column (II) into whose lower zone (IIb) alcohol in vapor phase is additionally fed. This involves a phase exchange at the coherent and the disperse phase at the transition from the prereactor to the distillation column. Preferably, in addition to the first prereactor, a further 3 prereactors are used which serve as holdup reactors.

    57.
    发明专利
    未知

    公开(公告)号:BR0110477A

    公开(公告)日:2003-04-01

    申请号:BR0110477

    申请日:2001-05-03

    Applicant: BASF AG

    Abstract: In a process for the continuous fractional distillation of mixtures comprising tetrahydrofuran, gamma-butyrolactone and/or 1,4-butanediol to give at least three fractions, the fractionation is carried out in an assembly of distillation columns comprising at least one dividing wall column or at least one assembly of thermally coupled conventional distillation columns.

    59.
    发明专利
    未知

    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

    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.

Patent Agency Ranking