Global Patent Index - EP 0356802 B1

EP 0356802 B1 19920729 - ELECTROCHEMICAL PROCESS FOR THE PRODUCTION OF CHROMIC ACID

Title (en)

ELECTROCHEMICAL PROCESS FOR THE PRODUCTION OF CHROMIC ACID

Publication

EP 0356802 B1 19920729 (DE)

Application

EP 89115030 A 19890815

Priority

DE 3829121 A 19880827

Abstract (en)

[origin: EP0356802A2] The present invention relates to a process for the production of chromic acid CrO3, of high purity on the basis of the electrochemical principle, the measures to be taken comprising the process steps: 1. preparation and purification of an aqueous sodium chromate/sodium dichromate solution, 2. conversion of said sodium chromate/sodium dichromate solution into a sodium dichromate/chromic acid solution, 3. crystallisation of chromic acid from said sodium chromate/chromic acid solution by evaporation, 4. separation of the crystallised chromic acid from the mother liquor, 5. recirculation of the separated mother liquor in the centrifuge.

IPC 1-7

C25B 1/22

IPC 8 full level

C25B 1/00 (2006.01); C25B 1/22 (2006.01); C25B 15/08 (2006.01)

CPC (source: EP KR US)

C25B 1/22 (2013.01 - EP KR US); C25B 15/02 (2013.01 - KR); C25B 15/085 (2021.01 - KR)

Citation (examination)

Designated contracting state (EPC)

DE ES FR GB IT

DOCDB simple family (publication)

EP 0356802 A2 19900307; EP 0356802 A3 19900516; EP 0356802 B1 19920729; AR 247252 A1 19941130; BR 8904252 A 19900410; CA 1338145 C 19960312; DD 284060 A5 19901031; DE 3829121 A1 19900301; DE 58901937 D1 19920903; ES 2042904 T3 19931216; JP 2812730 B2 19981022; JP H02104684 A 19900417; KR 0152524 B1 19981015; KR 900003418 A 19900326; MX 170481 B 19930825; PL 163883 B1 19940531; RO 107136 B1 19930930; TR 24735 A 19920306; US 5068015 A 19911126; ZA 896495 B 19900530

DOCDB simple family (application)

EP 89115030 A 19890815; AR 31475189 A 19890825; BR 8904252 A 19890824; CA 609439 A 19890825; DD 33209889 A 19890825; DE 3829121 A 19880827; DE 58901937 T 19890815; ES 89115030 T 19890815; JP 21618589 A 19890824; KR 890012190 A 19890826; MX 1709589 A 19890807; PL 28116589 A 19890825; RO 14122389 A 19890810; TR 67389 A 19890822; US 39373389 A 19890815; ZA 896495 A 19890825