EP 1006213 B1 20041215 - Process for regenerating a processing solution
Title (en)
Process for regenerating a processing solution
Title (de)
Verfahren zum Regenerieren einer Prozesslösung
Title (fr)
Procédé de régeneration d'une solution de traitement
Publication
Application
Priority
DE 19851180 A 19981106
Abstract (en)
[origin: DE19851180C1] Chemical reduction metal plating solution regeneration uses a weakly basic anion exchanger (T1) for hypophosphite ion recycle to the cathodic chamber (3) of a multi-chamber electrodialysis cell. An acid mixture, formed in the second chamber (6) by entry of protons from the anodic chamber (1), is supplied to a hypophosphite-loaded weakly basic anion exchanger with its outlet connected to the cathodic chamber. A chemical reduction metal plating solution, containing hypophosphite and ortho phosphite, is regenerated in a multi-chamber electrodialysis cell having two chambers separated from one another by an anion exchange membrane and which are located between a dilute acid-containing anodic chamber and a cathodic chamber, the first chamber being separated from the cathode chamber by an anion exchange membrane and the second chamber being separated from the anodic chamber by a cation exchange membrane. The solution is delivered to the first chamber for hypophosphite and orthophosphite ion transport from the solution to the second chamber and simultaneous hypophosphite ion transport from the cathodic chamber into the solution, the resulting regenerated solution being discharged for reuse. Preferred Features: Part of the solution, leaving the weakly basic anion exchanger (T1), may be passed over a plating metal ion-loaded, weakly acidic anion exchanger within the first chamber (5) of the cell (EZ). A regeneration circuit is formed by a connection (P1) between the cathodic chamber (3) and the second chamber (6). A further chamber may be provided between the anodic chamber (1) and the second chamber and separated from the second chamber by a cation exchange membrane, this further chamber receiving plating metal ions from the anodic chamber and being supplied with part or all of the process solution (PL) which is then transferred to the first chamber. Plating metal additions are made to the first chamber or to the anodic chamber. The anode (2) may be an insoluble anode, preferably of steel or platinized expanded titanium, or a soluble anode of the plating metal.
IPC 1-7
IPC 8 full level
C23C 18/16 (2006.01); C25D 21/22 (2006.01)
CPC (source: EP)
C23C 18/1617 (2013.01); C25D 21/22 (2013.01)
Designated contracting state (EPC)
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE
DOCDB simple family (publication)
EP 1006213 A2 20000607; EP 1006213 A3 20000809; EP 1006213 B1 20041215; AT E284980 T1 20050115; DE 19851180 C1 20000420; DE 59911270 D1 20050120
DOCDB simple family (application)
EP 99120998 A 19991104; AT 99120998 T 19991104; DE 19851180 A 19981106; DE 59911270 T 19991104