Sodium Cyanide, 143-33-9

Sodium Cyanide, 143-33-9

SODIUM CYANIDE

1. PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

CHEMICAL STRUCTURE AND DESCRIPTION:

Sodium Cyanide (NaCN) is the sodium salt of hydrocyanic acid (hydrogen cyanide). It consists of a sodium cation (Na⁺) and a cyanide anion (CN⁻). The cyanide ion features a carbon atom triple-bonded to a nitrogen atom (C≡N). This linear, highly polar ion is the source of the compound's extreme toxicity, as it acts as a metabolic poison by binding to the ferric ion (Fe³⁺) in cytochrome c oxidase, inhibiting cellular respiration. Sodium Cyanide is a white, highly water-soluble crystalline solid that is hygroscopic. It is used extensively in mining for gold and silver extraction, in electroplating, and as a chemical intermediate. Upon contact with acids, it releases extremely toxic hydrogen cyanide gas (HCN). Sodium Cyanide is a Schedule 3 substance under the Chemical Weapons Convention due to its potential for misuse.

Structural Features:

• Contains sodium cation (Na⁺) and cyanide anion (CN⁻)

• Linear cyanide ion with carbon-nitrogen triple bond (C≡N)

• Highly polar ionic compound

• Hygroscopic (absorbs moisture from air)

• Reacts with acids to release hydrogen cyanide gas (HCN)

2. PHYSICAL AND CHEMICAL PROPERTIES

3. SOLUBILITY PROFILE

4. CHEMICAL PROPERTIES AND REACTIONS

Key Chemical Reactions:

Acid Reaction (DANGEROUS):
NaCN + HCl → NaCl + HCN ↑ (hydrogen cyanide gas, extremely toxic)

Hydrolysis:
NaCN + H₂O → HCN + NaOH

Gold Complexation (Mining):
4Au + 8NaCN + O₂ + 2H₂O → 4Na[Au(CN)₂] + 4NaOH

Oxidation (to cyanate):
NaCN + 2H₂O₂ → NaOCN + 2H₂O

5. APPLICATIONS AND INDUSTRIAL USES

6. SPECIFICATIONS (TYPICAL)

7. HANDLING AND STORAGE

Critical Handling Notes:

• NEVER mix with acids or acid-forming materials (releases toxic HCN gas)

• Use only in designated areas with continuous gas detection and monitoring

• Emergency shower and eyewash stations must be readily accessible

• Detoxification solutions (e.g., sodium hypochlorite) must be available for spills

• Double containment systems recommended

• Strict lock-out/tag-out procedures for maintenance

• Specialized cyanide destruction methods required for waste management

8. SAFETY AND TOXICOLOGY

IMMEDIATE DANGER TO LIFE OR HEALTH (IDLH): 25 mg/m³

EXTREMELY TOXIC
FATAL IF SWALLOWED, INHALED, OR ABSORBED THROUGH SKIN
RAPIDLY INTERFERES WITH CELLULAR RESPIRATION

9. FIRST AID MEASURES

ANTIDOTE INFORMATION:

• First-line antidote: Hydroxocobalamin (Vitamin B12a) – 5 grams intravenous infusion

• Second-line: Sodium thiosulfate – 12.5 grams intravenous infusion

• Amyl nitrite (inhalation) may be used as an interim measure only

• Do NOT delay medical treatment

10. TRANSPORT INFORMATION

Transport Restrictions:

• Sodium Cyanide is subject to strict transport regulations

• Transport must be conducted in accordance with international and national hazardous materials regulations

• Special emergency response procedures apply

• NOT for transport as break-bulk cargo; shipping containers must be segregated from food and feed

11. REGULATORY INFORMATION

12. SUMMARY AND CRITICAL WARNINGS

SUMMARY:

Sodium Cyanide (NaCN, CAS 143-33-9) is a white, highly water-soluble crystalline solid with a faint almond-like odor. It has a molecular weight of 49.01 g/mol, density of approximately 1.6 g/cm³, and melting point of 563 °C. It is hygroscopic and reacts with acids to release extremely toxic hydrogen cyanide gas.

Its most important application is the extraction of gold and silver in mining via the cyanidation process. It is also used in electroplating, chemical synthesis, and as a laboratory reagent.

Sodium Cyanide is EXTREMELY TOXIC. It is fatal if swallowed, inhaled, or absorbed through skin. It rapidly interferes with cellular respiration by binding to cytochrome c oxidase, leading to death within minutes if untreated. It is classified under UN 1689, Class 6.1, Packing Group I. It is very toxic to aquatic life with long-lasting effects.

Storage must be in tightly sealed containers in cool, dry, well-ventilated areas, away from moisture, acids, heat, and oxidizing agents. NEVER mix with acids or acid-forming materials. In case of exposure, seek IMMEDIATE medical attention. Antidote treatment (hydroxocobalamin or sodium thiosulfate) must be administered under medical supervision.

Key Properties:

Critical Safety Points:

• EXTREMELY TOXIC: H300, H310, H330 (Fatal if swallowed, in contact with skin, or inhaled)

• ORGAN DAMAGE: H372 (Causes damage to organs through prolonged or repeated exposure)

• ENVIRONMENTAL HAZARD: H410 (Very toxic to aquatic life with long-lasting effects)

• ACID REACTION: Releases toxic hydrogen cyanide gas (HCN)

• STORAGE: Tightly sealed, cool, dry, well-ventilated, away from acids and moisture

• PROTECTIVE EQUIPMENT: Full personal protective equipment required

• ANTIDOTE: Hydroxocobalamin or sodium thiosulfate (under medical supervision)

CRITICAL WARNINGS:

1. EXTREME TOXICITY: Sodium Cyanide is one of the most toxic industrial chemicals. It can be fatal within minutes following ingestion, inhalation, or skin absorption. Immediate medical attention is essential. Antidote treatment under medical supervision is the only effective intervention.

2. ACID REACTION: Contact with acids releases HYDROGEN CYANIDE GAS (HCN) , an extremely toxic and rapidly acting gas. Fatal concentrations can be reached quickly. Sodium Cyanide must be stored away from all acids and acid-forming materials.

3. HYDROLYSIS: In the presence of moisture, Sodium Cyanide slowly hydrolyzes, releasing HCN gas. Protect from moisture and store in sealed containers in dry areas with continuous ventilation and gas detection.

4. CYANIDE DETOXIFICATION: Spills require immediate neutralization using sodium hypochlorite or hydrogen peroxide to destroy the cyanide ion. Specialized cyanide destruction methods are required for waste management. Environmental release must be strictly prevented.

5. REGULATORY CONTROLS: Sodium Cyanide is subject to strict regulatory controls, including permits, registration, security requirements, and transport restrictions. Compliance is mandatory. It is a Schedule 3 substance under the Chemical Weapons Convention.

Important Disclaimer: This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on available data and is believed to be accurate. However, the user is solely responsible for determining the suitability of the product for their specific applications and for complying with all applicable regulations and safety requirements. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are responsible for testing the product in their own processes and applications. All local, national, and international regulations must be followed when working with Sodium Cyanide. This material is EXTREMELY TOXIC and is strictly for industrial use only under highly controlled conditions. Due to its extreme toxicity, a detailed risk assessment and emergency response plan must be established prior to use. NEVER use Sodium Cyanide without proper training and protective equipment. In case of exposure, seek IMMEDIATE medical attention.