CHLOROSULFONIC ACID AND SULFUR TRIOXIDE MIXTURE

Diamond	Hazard	Value	Description
0 4 2 W ox	Health	4	Can be lethal.
	Flammability	0	Will not burn under typical fire conditions.
	Instability	2	Readily undergoes violent chemical changes at elevated temperatures and pressures.
	Special	W OX	Reacts violently or explosively with water. Possesses oxidizing properties.

A colorless to yellow fuming liquid with a pungent irritating odor. Corrosive to metals and tissue. It causes eye and skin burns. Ingestion causes severe burns of mouth, esophagus and stomach. Vapor is very toxic by inhalation. A fire risk in contact with organic materials such as wood, cotton, fiberboard.

• Strong Oxidizing Agent
• Known Catalytic Activity
• Water-Reactive

Fumes in air. Combines with water with explosive force(heat of dilution 504 cal/g) forming Sulfuric Acid, [Merck, 11th ed., 1989].

Chlorosulfonic acid reacts vigorously with water to generate gaseous HCl. Based on a scenario where the chemical is spilled into an excess of water (at least 5 fold excess of water), half of the maximum theoretical yield of Hydrogen Chloride gas will be created in 0.04 minutes. Experimental details are in the following: "Development of the Table of Initial Isolation and Protective Distances for the 2008 Emergency Response Guidebook", ANL/DIS-09-2, D.F. Brown, H.M. Hartmann, W.A. Freeman, and W.D. Haney, Argonne National Laboratory, Argonne, Illinois, June 2009.

Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

EXCEPT FOR ACETIC ANHYDRIDE (UN1715), THAT IS FLAMMABLE, some of these materials may burn, but none ignite readily. May ignite combustibles (wood, paper, oil, clothing, etc.). Substance will react with water (some violently), releasing corrosive and/or toxic gases and runoff. Flammable/toxic gases may accumulate in confined areas (basement, tanks, hopper/tank cars, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water. Substance may be transported in a molten form. (ERG, 2020)

Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

CORROSIVE and/or TOXIC; inhalation, ingestion or contact (skin, eyes) with vapors, dusts or substance may cause severe injury, burns or death. Fire will produce irritating, corrosive and/or toxic gases. Reaction with water may generate much heat that will increase the concentration of fumes in the air. Contact with molten substance may cause severe burns to skin and eyes. Runoff from fire control or dilution water may cause environmental contamination. (ERG, 2020)

CHLOROSULFONIC ACID decomposes explosively on contact with water, strong mineral acids and bases, alcohols, finely dispersed organic matter. Potentially violent reaction with acetic acid, acetic anhydride, acetonitrile, acrolein, acrylic acid, acrylonitrile, alkali, allyl alcohol, allyl chloride, ammonium hydroxide, aniline, butyraldehyde, cresol, cumene, diethyleneglycol methyl ether, diisopropyl ether, diphenyl ether, ethyl acetate, ethyl acrylate, ethylene chlorohydrin, ethylene diamine, ethylene glycol, glyoxal, hydrocarbons (hexane, heptane), hydrogen peroxide, isoprene, powdered metals, methyl ethyl ketone, propylene oxide, vinyl acetate and combustibles. When heated to decomposition, it emits toxic fumes of hydrogen chloride and oxides of sulfur [Sax, 9th ed., 1996, p. 831]. The acid is a strong oxidant, e.g., the reaction with phosphorus accelerates beyond control leading to explosion [Heumann, K. et al., Ber., 1882, 15, p. 417].

SULFUR TRIOXIDE reacts vigorously with oxygen difluoride. Explosions occur if the reaction is carried out in the absence of a solvent [J. Chem. Eng. Data 13(4):529-531 1968]. An excess in contact with tetrafluoroethylene causes explosive decomposition to carbonyl fluoride and sulfur dioxide [Chem. Eng. News 49(22):3. 1971]. Reacts violently and very exothermically with anhydrous perchloric acid [Pascal 16:300 1931-34]. Liquid sulfur trioxide reacts violently with nitryl chloride, even at 75°C. Reacts with lead oxide to cause a white luminescence [Mellor 7:654 1946-47]. Mixing chlorosulfuric acid and 98% sulfuric acid may evolve HCl [Subref: Anon, Loss Prev. Bull. 1977, (013), 2-3].

• Acids, Strong Oxidizing
• Acyl Halides, Sulfonyl Halides, and Chloroformates

Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below.

• Cellulose-Based Absorbents
• Mineral-Based & Clay-Based Absorbents
• Expanded Polymeric Absorbents
• Dirt/Earth

Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: See ERG Table 1 - Initial Isolation and Protective Action Distances on the UN/NA 1754 datasheet.

FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)

Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

When material is not involved in fire, do not use water on material itself.

SMALL FIRE: Dry chemical or CO2. If it can be done safely, move undamaged containers away from the area around the fire.

LARGE FIRE: Flood fire area with large quantities of water, while knocking down vapors with water fog. If insufficient water supply, responders should withdraw.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Cool containers with flooding quantities of water until well after fire is out. Do not get water inside containers. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2020)

Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Use water spray to reduce vapors; do not put water directly on leak, spill area or inside container. Keep combustibles (wood, paper, oil, etc.) away from spilled material.

SMALL SPILL: Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2020)

Excerpt from ERG Guide 137 [Substances - Water-Reactive - Corrosive]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE. Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. (ERG, 2020)

Normalized Breakthrough Times (in Minutes)

Chemical	CAS Number	State	QS	QC	SL	C3	TF	TP	RC	TK	RF
Chlorosulfonic acid	7790-94-5	Liquid	41		>480	330	>480	17	>480	>480	180
Chlorsulfonic acid	7790-94-5	Liquid	41		>480	330	>480	17	>480	>480	180
Sulfur trioxide	7446-11-9	Liquid				imm			90	90	90

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Excerpt from 137 [Substances - Water-Reactive - Corrosive]:

Call 911 or emergency medical service. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air if it can be done safely. Give artificial respiration if victim is not breathing. Do not perform mouth-to-mouth resuscitation if victim ingested or inhaled the substance; wash face and mouth before giving artificial respiration. Use a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Removal of solidified molten material from skin requires medical assistance. Keep victim calm and warm. Effects of exposure (inhalation, ingestion or skin contact) to substance may be delayed. (ERG, 2020)

• CHLOROSULFONIC ACID AND SULFUR TRIOXIDE MIXTURE
• CHLOROSULFONIC ACID-SULFUR TRIOXIDE MIXTURE
• CHLOROSULPHONIC ACID AND SULPHUR TRIOXIDE MIXTURE
• SULFUR TRIOXIDE AND CHLOROSULFONIC ACID MIXTURE
• SULPHUR TRIOXIDE AND CHLOROSULPHONIC ACID MIXTURE