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Product Name: p-Toluenesulfonic Acid Monohydrate
Alternate Name: para-Toluenesulfonic acid monohydrate, PTSA Monohydrate
Chemical Formula: C7H8SO3·H2O
CAS Number: 6192-52-5
Recommended Use: Catalyst in organic synthesis, esterification agent, acidifying agent
Supplier: Chemical supply distributors, academic research vendors
Contact Information: Keep the supplier’s emergency response details and operational contact on-hand
Emergency Numbers: Consult national or local poison control and fire authorities if acute exposure occurs
Classification: Corrosive to skin, serious eye damage, possible respiratory irritant
Main Hazards: Harmful in contact with skin and if inhaled, causes burns, possible allergic skin reaction, risk of damage to mucous membranes, corrosive to eyes
Pictogram: Corrosion, Exclamation mark according to GHS labeling
Signal Word: Danger
Hazard Statements: Causes severe skin burns and eye damage, may cause respiratory irritation
Precautionary Statements: Avoid breathing dust or fumes, use adequate protective clothing and eye protection, wash hands thoroughly after handling, do not eat or drink near the material, remove contaminated clothing promptly
Potential Acute Health Effects: Eye and skin burns, upper airway irritation, coughing, headache, chest discomfort
Chemical Name: p-Toluenesulfonic Acid Monohydrate
Synonyms: PTSA hydrate
Chemical Formula: C7H8SO3·H2O
CAS Number: 6192-52-5
Concentration: >98% pure as supplied in commercial and laboratory grades
Impurities: Trace amounts of anhydrous p-Toluenesulfonic acid possible based on storage and handling
Additional Ingredients: Product usually contains only the compound as listed, without significant stabilizers, dyes, or additives
Inhalation: Move affected person to fresh air, keep warm and at rest, seek immediate medical attention if symptoms like coughing or difficulty breathing develop
Skin Contact: Remove contaminated clothing, rinse the exposed skin thoroughly with plenty of water for at least fifteen minutes, get medical help for ongoing irritation or visible burns
Eye Contact: Rinse with water for a minimum of twenty minutes, hold eyes open to ensure full irrigation, remove contact lenses if easy to do so, seek urgent medical attention
Ingestion: Rinse mouth, do not induce vomiting, give small sip of water only if person is fully conscious, get immediate medical help
Advice to Physicians: Treat symptomatically, monitor for airway burns and respiratory complications, consider endoscopy if ingestion or severe burns suspected
Suitable Extinguishing Media: Water spray, dry chemical, alcohol-resistant foam, carbon dioxide
Unsuitable Media: Direct streams of water may spread corrosive acids
Special Hazards: Emits toxic and irritating fumes including sulfur oxides, organic vapors when heated strongly or in fire
Protective Equipment: Full protective suit including self-contained breathing apparatus recommended for large fires or significant fume exposure
Firefighting Procedures: Isolate fire area, cool containers with water to prevent explosion, avoid runoff into sewers, prevent contact with strong bases or oxidizers
Personal Precautions: Wear chemical-resistant gloves, safety goggles, acid-resistant clothing, avoid direct contact and inhalation
Environmental Precautions: Do not allow material to enter watercourses, drains, or soil
Spill Response: Use non-combustible absorbent material such as sand or earth, carefully collect and contain the spill, neutralize with sodium bicarbonate or dilute alkali, scoop into suitable sealed containers for disposal
Clean-Up: Flush area with water after collecting the bulk material, ventilate the area well, ensure all equipment used for clean-up is decontaminated
Reporting: Inform environmental and workplace authorities as required by local laws for hazardous releases
Handling: Use only in areas with adequate ventilation, avoid creating dust, handle with care to prevent splashing or exposure, leave containers sealed except for dispensing, no eating, drinking, or smoking around the material
Storage: Keep container tightly closed, store in a cool, dry, ventilated area away from incompatible materials such as bases, oxidizers, strong reducing agents, segregate from food and drink, use containers made of compatible materials such as glass or polyethylene
Hygiene Measures: Wash hands, arms, and face thoroughly after handling, launder contaminated clothing before reuse, provide emergency showers and eyewash stations nearby
Engineering Controls: Work in a chemical fume hood or well-ventilated area equipped with local exhaust, install spill containment if handling in bulk
Personal Protective Equipment: Acid-resistant gloves (nitrile or butyl rubber), safety goggles, face shield for splashing risk, long-sleeved laboratory coat or chemical apron, closed shoes
Respiratory Protection: Wear a respirator fitted with acid vapor cartridges if exposure limits may be exceeded or during spill response
Exposure Limits: No specific OSHA, NIOSH, or ACGIH limits set for p-Toluenesulfonic Acid Monohydrate, general acid exposure limit practices apply
Environmental Controls: Keep material away from sinks and environmental drains, use secondary containment for storage areas
Appearance: White or colorless crystalline powder
Odor: Faint, pungent
Odor Threshold: Not available
pH: Strongly acidic in aqueous solution
Melting Point: Around 103°C (monohydrate), decomposes on strong heating
Boiling Point: Decomposes before boiling
Solubility: Highly soluble in water, ethanol, methanol, acetone
Vapor Pressure: Not significant at ambient temperatures
Density: Roughly 1.24 g/cm³
Flash Point: Not flammable as supplied
Explosive Properties: Not explosive
Oxidizing Properties: Not classified as an oxidizer
Partition Coefficient: Not measured, high solubility in water
Chemical Stability: Stable under recommended conditions of storage and handling
Reactivity: Strong acid reacts vigorously with strong bases, produces toxic fumes if heated to decomposition, reacts with metal powders with hydrogen gas evolution possible
Conditions to Avoid: Exposure to moisture, high heat, contact with incompatible materials
Incompatible Materials: Bases, strong oxidizers such as sodium hypochlorite or nitric acid, reducing agents, cyanides, alkali metals
Hazardous Decomposition Products: Sulfur oxides, toluene vapors, carbon monoxide and carbon dioxide on combustion or thermal decomposition
Routes of Exposure: Skin, eye, ingestion, inhalation
Acute Toxicity: LD50 (rat, oral) around 2480 mg/kg (monohydrate), local tissue irritation common
Skin Corrosion/Irritation: Causes burns, especially at higher concentrations or longer contact
Serious Eye Damage/Irritation: Causes severe, potentially irreversible damage on contact
Respiratory Sensitization: Dust or fumes can irritate respiratory system, sensitive individuals at higher risk
Chronic Toxicity: Repeated or prolonged exposure can lead to dermatitis, respiratory discomfort, possible allergic responses
Carcinogenicity, Mutagenicity, Reproductive Toxicity: No classified risk noted in available data, not listed by IARC or NTP
Other Health Hazards: Individuals with pre-existing skin or respiratory conditions at increased risk of adverse effects
Ecotoxicity: Harmful to aquatic life due to low pH from acidification, may cause adverse effects on aquatic organisms at high concentrations
Persistence and Degradability: Substance expected to break down by natural hydrolysis and biological processes, but immediate acidification risk to water sources
Bioaccumulation: Not expected to bioaccumulate because of high water solubility
Mobility in Soil: High mobility, moves easily with water through soil and groundwater
Other Adverse Effects: Spills can sharply lower pH of aquatic habitats, rapid neutralization needed to reduce environmental harm
Waste Disposal Methods: Neutralize acid with sodium bicarbonate or lime before disposal, confirm neutralization by pH testing, collect in sealed containers labeled clearly as hazardous acid waste
Container Disposal: Rinse empty containers thoroughly, treat all rinse solution as contaminated waste
Regulatory Requirements: Dispose according to federal, state, and local regulations governing hazardous laboratory waste
Environmental Precautions: Never pour down drains or release to soil or water bodies, always use approved hazardous waste collection systems
UN Number: UN2585
Proper Shipping Name: p-Toluenesulfonic Acid, solid
Transport Hazard Class: 8 (Corrosive)
Packing Group: III
Labels: Corrosive (8) required for all transportation
Special Precautions: Use only secure, compatible packaging for transport, segregate from foodstuffs and incompatible materials, ensure all shipments are accompanied by safety documentation stating hazards
US Federal Regulations: Listed by TSCA inventory, subject to regulations for corrosives; not classified as a carcinogen under OSHA
Canada: Listed under DSL/NDSL; complies with applicable chemical classification regulations
EU (REACH): Subject to registration and notification under REACH, classified as a corrosive according to GHS/CLP
Other Global: Registered and regulated in most industrialized nations as a hazardous, corrosive chemical; check local and national inventories, labeling and documentation standards before import or use
Workplace Requirements: Training required for handlers, safety data sheet available at worksite, emergency procedures documented and accessible
