Material Safety Data Sheet for Molybdenum Disulfide

Identification

Substance Name: Molybdenum Disulfide
Synonyms: Molybdenum(IV) Sulfide, Moly Sulfide, MoS₂
Chemical Formula: MoS₂
CAS Number: 1317-33-5
Recommended Uses: Lubricant, Additive for greases and oils, Catalyst
Supplier Details: Manufacturer addresses, contact numbers, emergency phone contacts, and email for support
Emergency Overview: Black or dark gray powder, odorless, insoluble in water, stable under usual storage and handling conditions

Hazard Identification

Classification: Not classified as hazardous by OSHA or GHS; some forms may create dust that irritates eyes or respiratory tract
Physical Hazards: Dust may pose a risk of irritation to eyes, nose, and throat, no significant acute systemic toxicity
Health Hazards: Prolonged inhalation of high concentrations of dust may cause respiratory discomfort, coughing or throat dryness
Environmental Hazards: Not considered hazardous to aquatic life in typical release scenarios, but dust can mechanically affect water filtration and aquatic organisms
Label Elements: No pictograms required, precautionary statements for minimizing dust exposure and avoiding inhalation

Composition / Information on Ingredients

Chemical Name: Molybdenum Disulfide
Common Name: MoS₂
CAS Number: 1317-33-5
Concentration: Typically 98-100% pure
Impurities: Trace elements possible from mining sources, like iron, copper, or silica, usually below 2% by weight

First Aid Measures

Inhalation: Move affected person to fresh air, monitor breathing, and provide medical attention if symptoms persist
Eye Contact: Rinse gently with water for 10-15 minutes, remove contact lenses if present and easy to do, seek medical attention for irritation
Skin Contact: Wash thoroughly with soap and water, remove contaminated clothing, seek attention if irritation develops
Ingestion: Rinse mouth, drink water if conscious, do not induce vomiting, seek medical advice if large amounts swallowed
Important Symptoms: May cause mild mechanical irritation, persistent irritation or symptoms warrant medical evaluation

Fire-Fighting Measures

Suitable Extinguishing Media: Use carbon dioxide, dry chemical, foam, or water spray; do not use high-pressure water stream on dust
Hazardous Combustion Products: Sulfur oxides, molybdenum oxides released at high temperatures
Fire Hazards: Powdered material can create dust clouds; dust may combust in rare strong ignition scenarios, high temperatures produce sulfur dioxide
Firefighting Precautions: Firefighters wear self-contained breathing apparatus, avoid breathing combustion products, evacuate area if large quantities involved

Accidental Release Measures

Personal Precautions: Wear dust masks, protective goggles, and gloves to avoid dust inhalation and skin contact
Environmental Precautions: Prevent release to sewage, surface water, or ground if possible
Containment Methods: Collect spilled powder by vacuuming or damp sweeping to avoid dust generation
Cleanup Procedures: Gather material in suitable containers for disposal according to local regulations, ventilate area, wash site of spill with water if needed

Handling and Storage

Handling Precautions: Use local exhaust ventilation to minimize dust, handle in well-ventilated areas, avoid breathing dust, avoid contact with skin and eyes, use mechanical aids to minimize manual handling
Storage Conditions: Store in a cool, dry, well-ventilated area away from strong acids or oxidizers; tightly close containers
Special Sensitivities: Keep away from moisture and incompatible materials to maintain quality and prevent unwanted reactions

Exposure Controls and Personal Protection

Exposure Limits: OSHA PEL for molybdenum compounds (insoluble): 15 mg/m³ (total dust), 5 mg/m³ (respirable fraction); ACGIH TLV: 10 mg/m³ (inhalable), 3 mg/m³ (respirable)
Engineering Controls: Local exhaust ventilation, process enclosure for dusty operations, dust collection systems
Personal Protection: Respiratory protection when concentrations exceed limits, nitrile or chemical-resistant gloves, safety glasses or goggles, protective clothing for bulk handling
Hygiene Measures: Wash after handling, do not eat, drink, or smoke during use, launder clothing before reuse

Physical and Chemical Properties

Appearance: Black or dark gray powder
Odor: Odorless
Odor Threshold: Not applicable
pH Value: Not applicable (insoluble in water)
Melting Point: About 1,185°C (2,165°F)
Boiling Point: Decomposes before boiling
Flash Point: Not flammable
Evaporation Rate: Not applicable
Flammability: Not combustible under normal conditions
Vapor Pressure: Negligible
Vapor Density: Not applicable
Density: 5.06 g/cm³
Solubility: Insoluble in water, slightly soluble in acids
Partition Coefficient: Not determined
Auto-Ignition Temperature: Above 400°C (752°F)
Decomposition Temperature: > 1,000°C (1,832°F)
Appearance Notes: Does not liquefy at room temperature or atmospheric pressure, maintains powder form

Stability and Reactivity

Chemical Stability: Stable under ordinary storage and handling, does not react spontaneously with air or water
Reactivity: Reacts with strong oxidizing agents, acids, and some halogens at elevated temperatures
Hazardous Reactions: Produces toxic gases like sulfur oxides under fire or high heat conditions
Conditions to Avoid: Excessive moisture, strong oxidizers, temperatures above 400°C
Incompatible Materials: Strong acids such as nitric or sulfuric acid, oxidizing agents, fluorine
Hazardous Decomposition: Sulfur dioxide, molybdenum oxides, hydrogen sulfide under extreme scenario

Toxicological Information

Acute Toxicity: Not acutely toxic by ingestion, inhalation, or skin contact in animal studies
Irritation: Dust may cause mechanical irritation to eyes and upper respiratory tract
Sensitization: No evidence of skin or respiratory sensitization
Chronic Toxicity: Prolonged, excessive inhalation of dust may cause mild to moderate lung irritation, prolonged skin contact may cause dryness
Carcinogenicity: Not listed as a carcinogen by IARC, NTP, OSHA
Mutagenicity: No positive evidence in standard mutagenicity tests
Reproductive Toxicity: No established reproductive hazards in animal studies
Exposure Routes: Inhalation is the most significant occupational route, ingestion and dermal routes present low risk under normal use

Ecological Information

Aquatic Toxicity: Practically insoluble, does not bioaccumulate, low risk to aquatic life under regular conditions
Terrestrial Effects: Minimal soil mobility, may persist in soils but not known to migrate or cause significant ecological impacts
Degradation: Natural weathering gradually transforms molybdenum disulfide to oxides and sulfates over time
Environmental Fate: Most particles settle to sediments or soils, environmental persistence without toxic effects
Bioaccumulation: Does not show evidence of bioaccumulation in wildlife
Ecotoxicological Studies: Studies show little or no impact on aquatic species in standard environmental concentrations

Disposal Considerations

Waste Treatment Methods: Collect and place into sealed containers, consult local, state, and federal regulations for disposal
Disposal Recommendation: Avoid disposal in general waste or in the environment, may be handled as non-hazardous industrial waste unless mixed with hazardous materials
Contaminated Packaging: Rinse empty containers with water, dispose of according to official requirements, consider recycling or reuse options if available

Transport Information

UN Number: Not regulated for transport under UN, IMDG, IATA or DOT guidelines
Proper Shipping Name: Molybdenum Disulfide
Transport Hazard Class: Non-hazardous material
Packing Group: Not applicable
Special Precautions for Transport: Avoid dust generation, prevent packaging rupture during handling and shipment
Transport in Bulk: Not subject to special bulk transport requirements

Regulatory Information

OSHA Status: Not regulated as hazardous by OSHA Hazard Communication Standard
TSCA Inventory: Listed
SARA Title III: Not reportable under Sections 302, 304, 313
DSL/NDSL (Canada): Listed on Canadian Domestic Substances List
Other Regulations: Not subject to specific labeling or restrictions under many international regulations, check regional requirements for dust-generating substances in workplace
California Prop 65: This chemical does not appear on the California Proposition 65 list
REACH (Europe): Registered, no restriction for industrial or consumer use under current European legislation