CHEMICAL NAME:

Chlorine Dioxide

SYNONYMS/TRADE NAMES:

Chlorine Peroxide; "ClO₂"

CHEMICAL FAMILY:

Inorganic Compound

SHIPPING NAME (TDGR):

Not applicable -- shipment FORBIDDEN

PRODUCT INDENTIFICATION NO.:

NA 9191

FORMULA:

ClO₂

MOLECULAR WEIGHT:

67.45

CAS NO.:

10049-04-4

USES:

Pulp bleaching; water treatment; disinfection

MANUFACTURER & SUPPLIER

Emergency Telephone Numbers

Sterling Pulp Chemicals, Ltd.
2 Gibbs Road, Islington,
Ontario M9B 1R1, Canada

Transportation:

CANUTEC:

(613) 996 - 6666

WHMIS CLASSIFICATION(S):

C (Oxidizing Material)
D1B (Toxic)
E (Corrosive Material) F (Dangerously Reactive)

NAME

CONC. % by weight

CAS NO.:

Product Ident. No.

LD₅₀

LC₅₀

Chlorine Dioxide

0 to 30 (variable)

10049-04-4

NA 9191

292 mg/kg(rat, oral)

Not Available

STATE:

Gas, at normal temperatures. Normally used in solution in water

APPEARANCE:

Gas: Yellow/green.
Solution: Pale Yellow

ODOUR:

Similar to Chlorine or Ozone

SPECIFIC GRAVITY:

Not applicable

ODOUR THRESHOLD:

Not available. Characteristic smell very evident at 1 ppm.

VAPOUR PRESSURE:

Not applicable

BOILING POINT:

11°C

VAPOUR DENSITY:

2.4 (air = 1)
(for 100% CIO₂

FREEZING POINT:

-59°C

EVAPORATION RATE:

Not applicable

pH:

2 to 3 (8 g/L sol.)

SOLUBILITY IN WATER:

8 g/L @ 15°C (practical limit for stable solution)

COEFFICIENT OF WATER/OIL DISTRIBUTION:

Not available

BULK DENSITY

Not applicable

CONDITIONS OF FLAMMABILITY:

Chlorine dioxide gas may decompose with a pink/violet flame which may ignite combustible materials. This flame can be extinguished by diluting cooling with air. Chlorine dioxide is not flammable in the normal sense, as no air is required for it to burn.

MEANS TO EXTINGUISH

When combustibles are burning in the presence of chlorine dioxide (or other strong oxidizers) water is the only effective extinguishing medium.

HAZARDOUS COMBUSTION PRODUCTS:

Not applicable, but see "Hazardous Decomposition Products:, Section 5.

FLASH POINT & METHOD

Not applicable

AUTO-IGNITION TEMPERATURE:

Not applicable, but see "Chemical Stability", Section 5.

UPPER FLAMMABILITY LIMIT

Not applicable

LOWER FLAMMABILITY LIMIT

Not applicable

MECHANICAL IMPACT SENSIVITY:

Not applicable

STATIC DISCHARGE SENSITIVITY:

Sensitive

CHEMICAL STABILITY:

Chlorine dioxide is unstable. At partial pressures above about 120 mm Hg it will decompose spontaneously and explode. At higher pressures the explosions become more violent; at approximately 190 mm Hg explosion relief may be inadequate and rupture of the vessel may occur. These explosions can ignite combustible materials.

INCOMPATIBLE SUBSTANCES:

Chlorine dioxide is a powerful oxidizing agent, and is incompatible with combustible materials, oxidizable organic vapours, hydrogen sulphide, or metallic dusts. Fire may occur.

REACTIVITY CONDITIONS:

Highly reactive on contact with incompatible materials, and will decompose upon exposure to ultraviolet light or heat.

HAZARDOUS DECOMPOSITION PRODUCTS:

Chlorine and oxygen.

SKIN CONTACT:

Solutions are highly irritant.

SKIN ABSORPTION:

May be absorbed, causing tissue and blood cell damage.

EYE CONTACT:

Severely irritant. Exposure may cause visual disturbance, i.e. seeing haloes around lights.

INHALATION:

A severe respiratory irritant. May cause bronchospasm and pulmonary oedema, which may be delayed in onset. May also cause severe headache. All symptoms may be delayed and long-lasting. Long term exposure may cause chronic bronchitis. An LC50 value of 500 ppm/15m3 (rat) is quoted in the literature.

INGESTION:Not applicable except for solutions, in which case the symptoms would be expected to parallel those for inhalation.

EXPOSTURE LIMITS:

ACGIH 1992-93: TWA 0.1 ppm, STEL 0.3 ppm. Most legal limits are similar.

IRRITANCY:

Severe

SENSITIZATION:

No information is available.

CARCINOGENICITY:

Not listed by IARC or ACGIH

TERATOGENICITY & MUTAGENICITY:

Information not available.

REPRODUCTIVE TOXICOLOGY:

Information not available.

TOXICOLOGICAL SYNERGISM:

May have synergistic effects in conjunction with chlorine, other chlorine oxides, and chlorine fluorine compounds.

PROTECTIVE EQUIPMENT:

Use eye protection and impermeable gloves. Use of contact lenses should not be permmed when potentially exposed to this material. Persons in the vicinity of chlorine dioxide gas or solutions should carry a respirator suitable for escape purposes at all times, in case of accidental release of significant amounts of gas.

ENGINEERING CONTROLS:Good ventilation should be provided, so that chlorine dioxide levels are maintained below TLV at all times.

Good ventilation should be provided, so that chlorine dioxide levels are maintained below the TLV at all times.

LEAK OR SPILL PROCEDURES:Chlorine dioxide must not be discharged to the general environment. Storage tanks and other equipment should be provided with a bund (berm) to retain solution in the event of rupture. Making spilled solution alkaline will convert chlorine dioxide to chlorate and chlorite, stopping release of gas.

Chlorine dioxide must not be discharged to the general environment but may be discharged to mill sewer if allowable, otherwise storage tanks and other equipment should be provided with a bund (berm) to retain solution in the event of rupture. Treating spilled solution with caustic will convert chlorine dioxide to chlorate and chlorite, stopping release of gas in 15-20 minutes. Release may be stopped faster by adding hydrogen peroxide or white liquor after the caustic has made the solution alkaline. PROPER PERSONAL PROTECTIVE EQUIPMENT SHOULD BE WORN PRIOR TO TREATMENT.

WASTE CONTROL PROCEDURES:

Contained plant settling ponds containing organic matter will normally provide an environment in which residual chlorine dioxide will be reduced to harmless compounds quickly. Excessive amounts will kill bacteria used to treat wastes, necessitating restocking.

HANDLING PROCEDURES AND EQUIPMENT:

Equipment manufacturer's recommendations for design, operation and maintenance of equipment must be followed.

STORAGE:

The gas is not stored as such, as it is unstable. Solutions are stored in FRP or tile-lined tanks. These tanks should be provided with adequate air-sweep to ensure that explosive concentrations of chlorine dioxide do not build up.

SHIPPING INFORMATION:

Chlorine dioxide may not be shipped as gas or solution

SKIN:

Wash immediately using soap or mild detergent and water

EYES:

Flush immediately with plenty of lukewarm water, Continue to wash for 10 minutes, lifting eyelids occasionally. Get medical attention.

INHALATION:

Move the victim to fresh air. If breathing is stopped, commence artificial respiration. Get medical attention.

INGESTION:

DO NOT GIVE ANYTHING BY MOUTH OR INDUCE VOMITING IF THE PATIENT IS UNCONSCIOUS.
Give large amounts of water to dilute stomach contents.Get medical attention.

For further information contact Dr. G. Ranger of Sterling Pulp Chemicals, Ltd. Telephone: (416) 239-7111