Title:
ELECTROCHEMIAL PROCESS
Document Type and Number:
Japanese Patent JP3098422
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To effectively produce an alkali metal hydroxide by electrochemically treating a green liquor containing an alkali metal sulfide and an alkali metal carbonate, removing the alkali metal carbonate in the form of carbon dioxide and simultaneously oxidizing the metal sulfide.
SOLUTION: A green liquor obtained by heat-treating a bleaching effluent or a cooking effluent and containing an alkali metal sulfide and an alkali metal carbonate is introduced from an inlet 7 of an electrolytic cell 1 into an anode compartment 2 and electrochemically treated to remove the alkali metal carbonate in the form of carbon dioxide and oxidize the sulfide. The green liquor is converted into a polysulfide concentrated green liquor and discharged from an outlet 8. Alkali metal cations are transported through a cationic selective membrane 6 to a cathode compartment 3. Water is decomposed into hydrogen gas and hydroxide ions in the cathode compartment 3 and the hydrogen gas is discharged through an outlet 10 from an outlet 12 and the alkali metal hydroxide produced from the alkali metal cations and hydroxide ions is discharged from an outlet 11.
Inventors:
Johann Landforth
Bo Hakanson
Bo Hakanson
Application Number:
JP10872396A
Publication Date:
October 16, 2000
Filing Date:
April 05, 1996
Export Citation:
Assignee:
Eka Chemicals Akchevolague
International Classes:
D21C11/02; C25B1/14; D21C9/10; D21C11/00; D21C11/04; D21C; (IPC1-7): D21C11/02
Domestic Patent References:
| JP7189155A | ||||
| JP558601A | ||||
| JP5522051A |
Other References:
【文献】国際公開94/12720(WO,A1)
Attorney, Agent or Firm:
Tetsuya Ito