公开(公告)号：DE3160798D1

公开(公告)日：1983-09-29

申请号：DE3160798

申请日：1981-10-05

Applicant: BASF AG

Inventor： KOEHLER WALDEMAR DR ,  WOSTBROCK KARL-HEINZ DR ,  SALADIN GUENTER ,  HOLZKNECHT BERNHARD DR

IPC: C07C102/00 ,  C07C103/90

公开(公告)号：DE3887434D1

公开(公告)日：1994-03-10

申请号：DE3887434

申请日：1988-10-11

Applicant: BASF AG

Inventor： NEUBAUER GERALD DR ,  DE DECKER EMILE ,  FUCHS HUGO DR ,  HOLZKNECHT BERNHARD DR ,  RITZ JOSEF DR

IPC: C07D201/16

Abstract: Caprolactam is recovered from caprolactam distillation low boilers or high boilers or mixtures thereof by the following steps: (a) crystallizing a low or high boiler or a mixture thereof to form purified capro-lactam crystals and a mother liquor, (b) separating off the purified caprolactam crystals to leave a mother liquor, (c) recycling from 5 to 90% by weight of the mother liquor of stage (b) into stage (a) and transferring the remainder of the mother liquor into the subsequent stage (d), (d) crystallizing the remaining mother liquor portion from stage (c) to form caprolactam crystals and a mother liquor, separating off the caprolactam crystals of stage (e) (d) and recycling the same into stage (a) to leave a mother liquor, (f) recycling from 20 to 99% by weight of mother liquor of stage (e) into stage (d) and channeling out the remainder of the impurity-containing mother liquor of stage (e).

公开(公告)号：DE3168363D1

公开(公告)日：1985-02-28

申请号：DE3168363

申请日：1981-10-13

Applicant: BASF AG

Inventor： STOCKBURGER DIETER DR ,  SCHULTZ WILHELM ,  SCHMIDT JOHANNES E DR ,  WIRTH FRIEDRICH DR ,  HOFFMANN HERWIG DR ,  HOLZKNECHT BERNHARD DR ,  WINTERMANTEL KLAUS DR

IPC: C07D307/89 ,  C07C51/265 ,  C07C51/31

公开(公告)号：ES2048183T3

公开(公告)日：1994-03-16

申请号：ES88116802

申请日：1988-10-11

Applicant: BASF AG

Inventor： NEUBAUER GERALD DR ,  DE DECKER EMILE ,  FUCHS HUGO DR ,  HOLZKNECHT BERNHARD DR ,  RITZ JOSEF DR

IPC: C07D201/16

Abstract: Caprolactam is recovered from caprolactam distillation low boilers or high boilers or mixtures thereof by the following steps: (a) crystallizing a low or high boiler or a mixture thereof to form purified capro-lactam crystals and a mother liquor, (b) separating off the purified caprolactam crystals to leave a mother liquor, (c) recycling from 5 to 90% by weight of the mother liquor of stage (b) into stage (a) and transferring the remainder of the mother liquor into the subsequent stage (d), (d) crystallizing the remaining mother liquor portion from stage (c) to form caprolactam crystals and a mother liquor, separating off the caprolactam crystals of stage (e) (d) and recycling the same into stage (a) to leave a mother liquor, (f) recycling from 20 to 99% by weight of mother liquor of stage (e) into stage (d) and channeling out the remainder of the impurity-containing mother liquor of stage (e).

公开(公告)号：DE3875130D1

公开(公告)日：1992-11-12

申请号：DE3875130

申请日：1988-02-18

Applicant: BASF AG

Inventor： HOLZKNECHT BERNHARD DR ,  FUCHS HUGO DR ,  HETZEL ECKHARD ,  WINTERMANTEL KLAUS DR ,  THOMA PETER DR

IPC: B01D9/00 ,  B01D9/02 ,  B01D9/04 ,  C07B63/00 ,  C07C67/00 ,  C07C241/00 ,  C07C265/14 ,  C07D201/16

Abstract: Purificn. of crystals deposited as a 0.2-10mm thick layer on a cooling surface from a melt or soln. is effected by contacting the crystals with a wash liq. for 1-60 min at a temp. close to the m.pt. or solubility temp. of the crystal material. The crystals are then sepd. from the wash liq. and melted.

公开(公告)号：DE3735054A1

公开(公告)日：1989-04-27

申请号：DE3735054

申请日：1987-10-16

Applicant: BASF AG

Inventor： NEUBAUER GERALD DR ,  DECKER EMILE DE ,  FUCHS HUGO DR ,  HOLZKNECHT BERNHARD DR ,  RITZ JOSEF DR

IPC: C07D201/16

Abstract: Caprolactam is recovered from caprolactam distillation low boilers or high boilers or mixtures thereof by the following steps: (a) crystallizing a low or high boiler or a mixture thereof to form purified capro-lactam crystals and a mother liquor, (b) separating off the purified caprolactam crystals to leave a mother liquor, (c) recycling from 5 to 90% by weight of the mother liquor of stage (b) into stage (a) and transferring the remainder of the mother liquor into the subsequent stage (d), (d) crystallizing the remaining mother liquor portion from stage (c) to form caprolactam crystals and a mother liquor, separating off the caprolactam crystals of stage (e) (d) and recycling the same into stage (a) to leave a mother liquor, (f) recycling from 20 to 99% by weight of mother liquor of stage (e) into stage (d) and channeling out the remainder of the impurity-containing mother liquor of stage (e).

公开(公告)号：DE3708709A1

公开(公告)日：1988-10-06

申请号：DE3708709

申请日：1987-03-18

Applicant: BASF AG

Inventor： HOLZKNECHT BERNHARD DR ,  FUCHS HUGO DR ,  HETZEL ECKHARD ,  WINTERMANTEL KLAUS DR ,  THOMA PETER DR

IPC: B01D9/00

Abstract: A process for the purification of frozen-out crystal layers in which these crystal layers, after they have been frozen out of a melt or solution on a cooling surface, are brought into contact with a purification liquid and are thus purified over their entire thickness, are then separated from the purification liquid and are subsequently melted, characterised in that the temperature of the crystal layers and of the purification liquid is in the region of the melting point or solubility point, in that the material transfer at the phase interface is intensified by forced convection, and in that this purification is carried out in a time of from 1 minute to 60 minutes on layers having a thickness from 0.2 mm to 10 mm.