HSDB 909

HSDB 909 - Names and Identifiers

Name	Chlorosulfonic acid
Synonyms	UN1754 HSDB 909 chlorosulfonic Chlorosulfonic acid Chlorosulphuric acid Sulfric chlorohydrin sulfurochloridic acid Chloridosulfuric acid Sulfuric chlorohydrin acidechlorosulfonique Sulfuric acidchloride Monochlorosulfonic acid Monochlorosulfuric acid Sulfuric acidchlorohydrin Sulfonic acid, monochloride Chlorosulfonic acid (with or without sulfur trioxide) Chlorosulfonic acid (with or without sulfur trioxide) [UN1754] [Corrosive]
CAS	7790-94-5
EINECS	232-234-6
InChI	InChI=1/ClHO3S/c1-5(2,3)4/h(H,2,3,4)

HSDB 909 - Physico-chemical Properties

Molecular Formula	ClHO3S
Molar Mass	116.52
Density	1.753 g/mL at 25 °C (lit.)
Melting Point	-80°C
Boling Point	151-152 °C/755 mmHg (lit.)
Flash Point	158°C
Water Solubility	reacts
Solubility	Miscible with hydrocarbons.
Vapor Presure	1 mm Hg ( 25 °C)
Vapor Density	4 (vs air)
Appearance	Oily Liquid, Fuming In Air
Specific Gravity	1.753
Color	Yellow to brown
Merck	14,2165
pKa	-6.49±0.15(Predicted)
Storage Condition	Room Temperature, under inert atmosphere
Stability	Stable, but reacts violently with water. In case of spills, mop up with sand - do not add water. Reacts with most metals to yield (flammable) hydrogen gas. Incompatible with strong bases, carbonates,
Sensitive	Moisture Sensitive
Refractive Index	n20/D 1.433(lit.)
Physical and Chemical Properties	A colorless or yellowish fuming liquid with a pungent odor. Soluble in dichloroethane, tetrachloroethane, chloroform; Insoluble in carbon disulfide, carbon tetrachloride.

HSDB 909 - Risk and Safety

Hazard Symbols	C - Corrosive
Risk Codes	R14 - Reacts violently with water R35 - Causes severe burns R37 - Irritating to the respiratory system
Safety Description	S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
UN IDs	UN 1754 8/PG 1
WGK Germany	1
RTECS	FX5730000
TSCA	Yes
HS Code	28062000
Hazard Class	8
Packing Group	I

HSDB 909 - Nature

Open Data Verified Data

A colorless or yellowish fuming liquid with a pungent odor. Melting Point -80 °c. Boiling point 158 °c. Relative density dl8 1.766. Soluble in dichloroethane, tetrachloroethane, chloroform; Insoluble in carbon disulfide, carbon tetrachloride. When alcohol and acid is decomposed. Is contained quite weak
S- Cl bond of strong acids. Smoke in the air. The reaction with water occurs vigorously to produce hydrochloric acid, sulfuric acid and smoke. Exothermic reactions occur with many organic combustible substances, nitrates, chlorates, carbides, sulfides, cyanides and metal powders. It reacts with organic compounds such as hydrocarbons, alcohols, phenols and amines to form organic derivatives. Pyrosulfuryl chloride is formed upon contact with a strong dehydrating agent such as sulfur trioxide and the like. It is highly hygroscopic and corrosive.

Last Update：2025-06-10 22:55:16

HSDB 909 - Preparation Method

Open Data Verified Data

gas synthesis method: sulfur dioxide gas generated by sulfur combustion is sent to the catalytic converter with each vanadium catalyst for conversion into sulfur trioxide after cooling and separation, and then sent to the synthesizer after cooling, reaction with dry hydrogen chloride gas (synthesized with hydrogen and chlorine, content> 85% HCI) is carried out at 130-230 deg C, and then cooled, gas-liquid separation, obtained chlorosulfonic acid product.
excessive hydrogen chloride, sulfur dioxide, sulfur trioxide and a small amount of chlorine gas are generated in the production process. Generally, a high-efficiency absorption tower is used to absorb hydrogen chloride with water to prepare hydrochloric acid; Sulfur dioxide and sulfur trioxide are absorbed with concentrated sulfuric acid.

Last Update：2022-01-01 10:59:43

HSDB 909 - Application

Open Data Verified Data

It is mainly used in the manufacture of sulfonamides, saccharin and sulfonating agents for the manufacture of dye intermediates. It is also used in the manufacture of pesticides, detergents, ion exchange resins, plastics, etc., and is used as a smoke agent in the military.

Last Update：2025-08-19 16:24:40

HSDB 909 - Safety

Open Data Verified Data

should be installed in a special tank car or special metal tank, tank car and tank should be cleaned regularly. Can should be tightly sealed, and then put into a solid wooden box or iron drum, the box with non-combustible materials as a liner, the external use of iron wire or iron sheet tight. Can not exceed 50kg net weight per box. Packaging capacity
The device shall be painted with marks, including the name of the manufacturer, the name of the product, the net weight, etc., as well as the "corrosion product" sign and the "wet" sign. Belongs to the first class of inorganic acid corrosion articles, risk code number: GB 8.1 class 81023. UN,N0,1754; IMDG CODE 8144 pages,
8, class 1. Store in a cool, dry, well-ventilated warehouse. The temperature of the library is not more than 35 degrees C, and the relative humidity is not more than 80%. The packaging must be sealed and free from moisture. It should be stored separately from easy (combustible) materials, acids, alkalis, alcohols, active metal powders, etc., and mixed storage is not required. In case of rain or snow during transport, it shall be covered with water-repellent devices. Packaged products must not be stacked, tilted or tumbled. During loading and unloading, care should be taken to prevent package breakage. Toxicity and protection: strong oxidant. In the case of water, it decomposes sharply, generating a large amount of heat and smoke, and even explosion. Contact with metal in humid air can corrode metal and release hydrogen, which is easy to burn and explosion. Contact with combustible materials (such as benzene) and combustible materials (such as sugar, cellulose, etc.) can occur violent reaction, and even cause combustion. Highly corrosive. Its vapor has a significant stimulating effect on the mucosa and respiratory tract. The clinical manifestations were shortness of breath, Cough, chest pain, dry throat pain and tears, Rhinorrhea, bloody sputum, Nausea, weakness and so on. Such as inhalation, nose, throat stimulation, sneezing, sore throat, runny nose and other symptoms, should be immediately given oxygen, and sent to the hospital for treatment. Tooth erosion can be caused by long-term contact. High concentration inhalation in addition to the upper respiratory tract irritation, Cough, Dyspnea or shortness of breath, pulmonary edema; Such as eating, can cause mouth, throat, esophagus and stomach burns, severe pain, bleeding, Vomit, diarrhea and blood pressure dropped sharply. If you accidentally splash into the eyes, you should immediately rinse with a large amount of flowing water for 15min and send it to the hospital for treatment; If it comes into contact with the skin, it can cause serious burns, Must be quickly washed with cold water, and then coated with 3% sodium bicarbonate solution or medicinal coconut oil. Operators should wear acid-proof fabric work clothes, wearing protective glasses, latex gloves, rubber aprons, and long rubber boots. Production equipment should be closed, workshop ventilation should be good. Regular medical examinations should be performed before employment and every two years. When there is a fire, the fire can be put out by using sand and dry powder fire retardants, and water is strictly prohibited.

Last Update：2025-06-10 22:55:16

HSDB 909 - Reference Information

pH range	1
LogP	-0.003 at 25℃
EPA chemical substance information	information provided by: ofmpeb.epa.gov (external link)
toxicity	its vapor is irritating to the eyes and mucous membranes. If inhaled, oxygen should be given immediately and sent to the hospital for treatment; If accidentally splash into the eyes, it should be immediately washed with water and sent to the hospital for treatment, can cause serious burns, must be quickly washed with cold water, and then coated with 3% sodium bicarbonate solution or medicinal oil. Operators should wear acid-proof fabric work clothes, wearing protective glasses, latex gloves, rubber aprons, and long rubber boots. Production equipment should be closed, workshop ventilation should be good. Regular medical examinations should be performed before employment and every two years.
Use	mainly used in the manufacture of saccharin and sulfonamide drugs, as sulfonating agent in dye synthesis, and as smoke agent in military, also used in the manufacture of ion exchange resins, plastics, pesticides, etc. used in the manufacture of sulfonyl compounds, saccharin, military toxic gases, etc. mainly used in the manufacture of sulfonamides, saccharin and sulfonating agents for the manufacture of dye intermediates are also used in the manufacture of pesticides, detergents, ion exchange resins, plastics, etc., and are used as smoke agents in the military. chlorosulfonic acid is used for the synthesis of 2,4, 5-trichlorobenzenesulfonyl chloride, an intermediate of the acaricide triclosone, and for the synthesis of saccharin and sulfonamides, as well as for the manufacture of detergents, ion exchange resins, plastics, sulfonating agents for dye intermediates, etc., are used as smoke agents in the military. manufacture of sulfonamides, reactive dyes, detergents, plastics, pesticides, saccharin and defense industry raw materials.
production method	the preparation of chlorosulfonic acid is divided into two methods: gas phase and liquid phase: 1. Gas phase method: sulfur trioxide and hydrogen chloride two kinds of gas into the reactor for the role of chemical combination, after cooling is condensed into chlorosulfonic acid, this method is suitable for a large number of preparations, because the equipment requires special materials, the investment is large. 2. Liquid phase method: using crude chlorosulfonic acid or concentrated sulfuric acid as mother liquor, sulfur trioxide is introduced into the mother liquor for absorption, and then hydrogen chloride is used to make the two gases play a chemical role in the liquid phase to generate chlorosulfonic acid. This method can be prepared on a small scale. The chlorosulfonic acid is produced by gas synthesis. Sulfur dioxide gas generated by combustion of sulfur is cooled and separated, then sent to a catalytic converter equipped with a vanadium catalyst for conversion to sulfur trioxide, and then sent to a synthesizer after cooling, with dry hydrogen chloride gas (hydrogen and chlorine synthesis, content> 85% HCl) at 130~230 deg C reaction, and then cooled, gas-liquid separation, chlorosulfonic acid product. In the production process, excess hydrogen chloride, sulfur dioxide, sulfur trioxide and a small amount of chlorine gas are generated. Generally, a high-efficiency absorption tower is used to absorb hydrogen chloride with water to make hydrochloric acid, and sulfur dichloride and sulfur trioxide are absorbed with concentrated sulfuric acid. sulfur dioxide gas is generated from sulfur dioxide combustion by gas synthesis, which is cooled and separated, and then sent to a catalytic converter equipped with a vanadium catalyst for conversion to sulfur trioxide, After cooling, it is sent to the synthesizer to react with dry hydrogen chloride (synthesized with hydrogen and chlorine, content> 85% HCl) at 130~230 ℃, and then cooled and gas-liquid separated, chlorosulfonic acid product was obtained. In the production process of 2SO2 + O2 → 2SO3SO3 + HCl → HSO3C1, excessive hydrogen chloride, sulfur dioxide, sulfur trioxide and a small amount of chlorine gas are generated. Generally, a high-efficiency absorption tower is used to absorb hydrogen chloride with water to form hydrochloric acid, sulfur trioxide was absorbed with concentrated sulfuric acid.
category	corrosive article
toxicity grade	high toxicity
flammability hazard characteristics	flammable in case of organic matter, H pore forming agent; Toxic chloride with water or high thermal decomposition, sulfur oxide gas
storage and transportation characteristics	The warehouse was ventilated and dried at low temperature, separate storage of cyanide
extinguishing agent	sand and carbon dioxide. No use of water
Occupational Standard	TWA 1 mg/m3
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)