公开(公告)号：DE58904556D1

公开(公告)日：1993-07-08

申请号：DE58904556

申请日：1989-09-08

Applicant: BASF AG

Inventor： VOSS HARTWIG DR

IPC: B01D61/52 ,  B01D57/02 ,  B01D61/44 ,  C02F1/469 ,  C09B67/54

公开(公告)号：DE3785552D1

公开(公告)日：1993-05-27

申请号：DE3785552

申请日：1987-12-04

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  BRUECKEN THOMAS DR

IPC: B01D61/44 ,  C25D13/24

Abstract: In acid removal from cathodic electro-dip lacquering baths, employing ultrafiltration, the novelty is that the ultrafiltrate is further processed by (a) passage through the chambers K1 of an electrodialysis cell ZA having the characteristic sequence (K2-M1-K1-M1)n (M1 = anion exchange membranes; n = 1 to 500), while an aq. base is passed through the chambers K2; (b) passage through the chambers K1 of an electrodialysis cell ZB having the characteristic sequence (K2-M1-K1-M2)n (M1 = anion exchange membranes; M2 = bipolar membranes), while water or an electrolyte (pref. the acid to be sepd. and/or a salt of this acid) is passed through the chambers K2; or (c) passage through the chambers K1 of an electrodialysis cell ZC having the characteristic sequence (K3-M1-K1-M1-K2-M2)n (M1 = anion exchange membranes; M2 = cation exchange membranes), while an aq. base is passed through the chambers K2 and water or an electrolyte (pref. the acid to be sepd. and/or a salt of this acid) is passed through the chambers K3. Electrodialysis is carried out at up to 100 mA/sq.cm. current density, the requisite electric field being applied by two electrodes at the ends of the cell (ZA, ZB or ZC).

公开(公告)号：AT89339T

公开(公告)日：1993-05-15

申请号：AT87112627

申请日：1987-08-29

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  BRUECKEN THOMAS DR

IPC: C25D13/24

公开(公告)号：DE4041571A1

公开(公告)日：1992-06-25

申请号：DE4041571

申请日：1990-12-22

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  SCHNEIDER ROLF DR

IPC: B01D61/44 ,  C07C303/02 ,  C07C303/44 ,  C07C309/04

Abstract: Process for liberating organic sulphonic acids from aqueous solutions of their salts, in which the aqueous organosulphate solution is electrodialysed with the aid of an electrodialysis cell which is assembled from diluate chambers KD, acid chambers KS and base chambers KB according to the sequence I (MB/KS/MA/KD/MK/KB)n I in which MB represents a bipolar ion exchanger membrane, MA represents an anion exchanger membrane, MK represents a cation exchanger membrane and n represents a number from 1 to 500.

公开(公告)号：DE3868243D1

公开(公告)日：1992-03-12

申请号：DE3868243

申请日：1988-11-24

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  BRUECKEN THOMAS DR

IPC: C25D13/24

Abstract: Method of removing acid from cathodic lacquer coating bath consists of separating the dispersion by means of ultra-filtration into the resin dispersion and the ultra-filtrate and de-acidifying the latter by passing through the chambers K, of an electrodialysis cell operating with a DC and having the characteristic sequence -(K2-M1-K1-M1)n- in which M1 are the anion exchange membranes and n is 1-500 while an aqueous base is passed through chambers K2. During the electrodialysis the electric field which carries out the ions transport through the membranes is changed by alternating the polarity.

公开(公告)号：AT72270T

公开(公告)日：1992-02-15

申请号：AT88119549

申请日：1988-11-24

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  BRUECKEN THOMAS DR

IPC: C25D13/24

公开(公告)号：DE3629981A1

公开(公告)日：1988-03-17

申请号：DE3629981

申请日：1986-09-03

Applicant: BASF AG

Inventor： VOSS HARTWIG DR ,  BRUECKEN THOMAS DR

IPC: C25D13/24 ,  C08J11/00 ,  B01D13/00

Abstract: The present invention relates to a novel process for removing acids from cathodic electrocoating baths, in which electrically conductive substrates are coated with cationic resins present in the form of aqueous dispersions, part or all of the dip-coating bath being subjected to an ultrafiltration in which the ultrafiltration membrane retains the cationic resin and an ultrafiltrate is formed which contains water, solvent, low molecular weight substances and ions, and part or all of the ultrafiltrate being recycled to the coating bath, in which process (a) part or all of the ultrafiltrate, before recycling to the electrocoating bath and (b) an aqueous solution of an organic or inorganic base, which may or may not contain salts, are each introduced into one or more chambers, separated from one another by an anion exchange membrane, of an exchange cell, solutions (a) and (b) being led over the surface of the membrane.