Membrane electrolytic cell for minimizing hypochlorite and chlorate formation

Patent · Tue Jul 09 00:00:00 EDT 1985

OSTI ID:6466749

Fair, D L; Justice, D D; Woodard, Jr, K E

An electrolytic cell for the electrolysis of an alkali metal chloride brine is comprised of an anode compartment and a cathode compartment separated by a cation exchange membrane. The anode is comprised of an unflattened expanded structure of a valve metal selected from the group consisting of titanium, tantalum, niobium, and alloys thereof. At least one side of the anode has as the electrochemically active surface an electrodeposited layer of a valve metal oxide. A plurality of cracks traverse the electrodeposited layer and a coating of a platinum metal group oxide covers the electrodeposited layer and substantially fills the cracks. The cationic exchange membrane is comprised of a laminated structure having a first surface adapted to contact an anolyte in which the ion exchange groups are predominately sulfonic acid groups. The first surface is also in contact with the electrochemically active surface of the anode. A second surface of the cation exchange membrane, adapted to contact a catholyte, has ion exchange groups which are predominately carboxylic acid groups. The cathode positioned in the cathode compartment is spaced apart from the cation exchange membrane. The cell operates with both a low chlorine overvoltage and a low oxygen overvoltage. During electrolysis of alkali metal chloride brines, the formation of hypochlorite and chlorate ions is minimized and the alkali metal hydroxides produced have low chlorate concentrations and are suitable for use without further treatment in chlorate-sensitive applications. Spent brine treatment is simplified and at reduced costs.

• Assignee: Olin Corp.
• Patent Number(s): US 4528077
• OSTI ID: 6466749
• Resource Relation: Patent File Date: Filed date 2 Jul 1982; Other Information: PAT-APPL-394464
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALKALI METALS
ELECTROLYSIS
PRODUCTION
CHLORINE
ELECTROLYTIC CELLS
DESIGN
FABRICATION
HYDROXIDES
ANODES
BRINES
CATHODES
CHLORATES
CHLORIDES
COATINGS
ELECTRODEPOSITION
ION EXCHANGE MATERIALS
NIOBIUM
PLATINUM
TANTALUM
TITANIUM
VALVES
WASTE PROCESSING
CHLORINE COMPOUNDS
CONTROL EQUIPMENT
DEPOSITION
ELECTRODES
ELEMENTS
EQUIPMENT
FLOW REGULATORS
HALIDES
HALOGEN COMPOUNDS
HALOGENS
HYDROGEN COMPOUNDS
LYSIS
MANAGEMENT
MATERIALS
METALS
NONMETALS
OXYGEN COMPOUNDS
PLATINUM METALS
PROCESSING
SURFACE COATING
TRANSITION ELEMENTS
WASTE MANAGEMENT
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
400400 - Electrochemistry