Material Safety Data Sheet: Molybdenum Electrode

Identification

Product Name: Molybdenum Electrode
Chemical Name: Molybdenum
Synonyms: Mo Electrode, Moly Bar, Pure Molybdenum Rod
Chemical Formula: Mo
CAS Number: 7439-98-7
Manufacturer: Refer to the label or supplier
Emergency Contact: Refer to data provided by local distributor

Hazard Identification

Classification: Not classified as hazardous under GHS for solid form
Health Hazards: Dust or fumes may irritate respiratory tract; prolonged exposure may affect lungs
Environmental Hazards: Not expected under normal conditions; dust could affect aquatic life when released
Physical Hazards: Dust from grinding or cutting may pose fire or explosion risks; bulk solid does not
Signal Word: None required for solid
Pictograms: None required for solid
Hazard Statements: Fine particles may cause fire/explosion hazard if air concentrations are excessive, especially during mechanical processing
Precautionary Statements: Avoid inhaling dust/fumes; use protection when machining

Composition / Information on Ingredients

Chemical Identity: Molybdenum
Content: Typically ≥99.95%
Impurity Elements: Trace metallics — usually tungsten, tantalum, and others below 0.05%
Other Ingredients: None for pure electrode

First Aid Measures

Inhalation: Move affected person to fresh air; seek medical attention if discomfort continues
Eye Contact: Rinse eyes with clean water for several minutes; seek attention for persistent irritation
Skin Contact: Wash thoroughly with soap and water; remove contaminated clothing
Ingestion: Rinse mouth; seek advice if large amounts ingested or symptoms appear

Fire-Fighting Measures

Suitable Extinguishing Media: Use suitable media for surrounding fire; Class D extinguishers (dry powder) recommended for metal powder
Special Hazards: Dust can burn in certain conditions; avoid water on burning metal dust
Specific Methods: Firefighters should wear appropriate protective equipment; move containers from fire area if safe
Hazardous Combustion Products: Metal oxides may form in a fire

Accidental Release Measures

Personal Precautions: Use respiratory protection if dust present; wear gloves and safety glasses
Environmental Precautions: Prevent dust from entering drains or watercourses
Containment/Cleanup: Collect material without creating dust; vacuum preferred for dust (use explosion-proof device); large solid pieces can be picked up mechanically

Handling and Storage

Safe Handling: Minimize dust generation; use local exhaust when machining; wash hands after handling
Storage Conditions: Store in a cool, dry, well-ventilated area; keep separate from acids and strong oxidizers
Incompatibilities: Avoid storage with reactive materials like fluorine, chlorine, or oxidizers

Exposure Controls and Personal Protection

Occupational Exposure Limits: OSHA PEL for molybdenum insoluble compounds: 15 mg/m³ (total dust), ACGIH TLV for inhalable fraction: 3 mg/m³
Engineering Controls: Local exhaust ventilation required when generating dust/fumes
Respiratory Protection: Use NIOSH-approved respirators for dust/fume conditions
Eye Protection: Safety glasses or goggles
Hand Protection: Protective gloves
Skin Protection: Protective clothing for repeated or prolonged contact

Physical and Chemical Properties

Appearance: Grey metallic solid (rod, bar, or electrode shape)
Odor: Odorless
Melting Point: 2623°C
Boiling Point: 4639°C
Density: 10.2 g/cm³ at 20°C
Solubility in Water: Insoluble
Vapor Pressure: Negligible at ambient temperatures
Molecular Weight: 95.95 g/mol
Other Properties: High electrical and thermal conductivity, ductile at high temperature

Stability and Reactivity

Chemical Stability: Stable under normal conditions
Reactivity: Not reactive with most substances at room temperature
Conditions to Avoid: High temperatures, strong acids, oxidizers
Hazardous Decomposition Products: Molybdenum oxides on oxidation
Hazardous Polymerization: Not expected

Toxicological Information

Acute Toxicity: Generally low for solid form; dust or fumes can irritate nose, throat, and lungs
Chronic Effects: Prolonged inhalation of dust or fumes may cause metal fume fever-like symptoms; animal studies suggest very high exposures can impact liver and kidneys
Carcinogenicity: Not classified by IARC or NTP
Sensitization: Not expected
Mutagenicity: Not expected
Reproductive Toxicity: No significant effects reported for workplace exposures

Ecological Information

Ecotoxicity: Bulk solid not hazardous; fine particles may affect aquatic organisms
Persistence and Degradability: Elemental form; not subject to biological degradation
Bioaccumulation: Unlikely under typical exposure scenarios
Mobility in Soil: Solid, minimal movement
Other Adverse Effects: Avoid uncontrolled release of dust, especially to water bodies

Disposal Considerations

Waste Disposal Methods: Recycle material whenever possible; dispose unused product or scrap at approved facility in line with local, regional, and national regulations
Hazardous Waste: Molybdenum solid generally not a listed hazardous waste; contain and avoid generating dust during disposal
Empty Containers: Treat as industrial waste; clean thoroughly before recycling or disposal

Transport Information

UN Number: Not regulated for solid
Transport Hazard Class: Not classified as dangerous for road (ADR), sea (IMDG), air (IATA)
Packing Group: Not assigned
Special Precautions: Do not transport with incompatible substances; ensure packaging guards against physical damage and dust spread

Regulatory Information

TSCA: Listed
REACH: Exempt as an elemental metal
OSHA: Not classified as hazardous chemical in solid form
WHMIS: Not classified as hazardous
RoHS: Not restricted
Other Regulations: Product ingredients comply with most national and international workplace safety standards; refer to regional requirements for environmental release or exposure limits