Ammonium Persulfate: Etchant for copper-plated PC Boards

AMMONIUM PERSULFATE – (NH₄)₂S₂O₈
(ammonium peroxydisulfate; peroxydisulfuric acid, diammonium salt)

Description:

• Colorless to light straw crystals or powder. Odorless.
• Strong oxidizer.
• Hazard classes: 5.1 oxidizer; 6.3 acute health hazard.
• CAS No.: 7727-54-0
• UN-NA No.: 1444

NFPA 704 Placarding Information:

• Health – 2
• Flammability – 0
• Reactivity – 1
• Special Notice – OX

Uses:

• Oxidizer and bleaching agent.
• Used in photography; electroplating; preserving food; depolorizing batteries; and washing infected yeast.
• Etchant for printed circuit boards and copper.
• In the manufacture of other persulfates, deodorizing and bleaching oils, and aniline dyes.

Reactivity and Fire Risk:

• Normally stable when pure and dry.
• Hazardous polymerization cannot occur.
• Incompatible with: sodium peroxide; iron; solutions of ammonia and silver salts; powdered aluminum and water; zinc and ammonia; sodium oxide; and hydrogen.
• Explosion hazard when mixed with finely powdered organic material, metal powder, or reducing agents.
• Non-combustible. It is a strong oxidizer capable of igniting combustible materials.
• Heating or contact with water releases oxygen and may intensify existing fire.

Health Hazards:

• Causes irritation or burns to eyes, skin, and respiratory tract.
• Possible allergic reaction with tearing, difficulty breathing and life-threatening shock.

Personal Protective Equipment:

• Normal conditions: Wear chemical safety glasses or goggles and any other protective clothing to prevent any possibility of exposure to skin.
• Fire conditions: Wear full protective clothing with full-faced, positive pressure SCBA.

Inspection and Storage Tips:

• Store in cool, dry area away from sources or heat or moisture.
• Must be stored away from incompatible materials as well as strong reducing agents and combustible materials.
• Avoid storage on wooden floors.

Article 80 Storage Information:

Class 2 oxidizer.

S occupancy exempt amounts allowed per control area:

Unprotected by sprinklers or approved storage cabinets: 250 pounds

In sprinkled building, not within approved storage cabinets: 500 pounds

In un-sprinkled building, within approved storage cabinets: 500 pounds

In sprinkled building, within approved storage cabinets: 1000 pounds

For storage of quantities exceeding the allowed exempt amounts for an S occupancy, the storage facility must conform to H-7 occupancy requirements as outlined in the Uniform Building Code.

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