Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Symclosene

Symclosene is needles from ethylene chloride with a chlorine odor.

CAS 87-90-1 C3Cl3N3O3 232.41 g/mol Danger

01 · Identification

What Symclosene is

Symclosene is needles from ethylene chloride with a chlorine odor. Its molecular formula is C3Cl3N3O3 and its molecular weight is 232.41 g/mol. It melts at 235 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as reactive agents - 2nd degree.

CAS number87-90-1
EC number201-782-8
Index number613-031-00-5
Molecular formulaC3Cl3N3O3
Molecular weight232.41 g/mol
Chemical class Reactive agents - 2nd degree

Other names for Symclosene

  • trichloroisocyanuric acid
  • trichloro-1,3,5-triazinetrion

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Symclosene
CodeHazard statement
H272 May intensify fire; oxidiser.
H302 Harmful if swallowed.
H335 May cause respiratory irritation.
H319 Causes serious eye irritation.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Supplemental EU statements: EUH031

Precautionary statements: P264, P270, P273, P280, P301, P305, P312, P313, P330, P337, P338, P391, P501

03 · Physical and chemical properties

Symclosene properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Melting point 235 °C (455 °F) DOE PAC
246.7 °C (476.1 °F) decomposes, decomposes HSDB
Density 2.07 g/cm³ ICSC
1 g/cm³ DOE PAC
1 g/cm³ at 20 °C, est CAMEO
Solubility Soluble in chlorinated and highly polar solvents HSDB
Solubility in water at 25 °C = 1 g/100 g; Solubility in acetone at 30 °C = 35.0 g/100 g at 25 °C HSDB
Water solubility = 1.2% = 1.20X10+4 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 1.2e-7 mmHg Haz-Map
negligible ICSC
Flash point 250 °C (482 °F) above this value HSDB
Lower explosive limit (LEL) Closed containers may rupture violently when heated. HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Fire and explosion

Fire and explosion behaviour of Symclosene

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Fire and explosion

Calcium hypochlorite and trichloro-s-triazinetrione were tested in a bomb apparatus measuring temperature and gas production. Combining the two chlorinators at 2, 6, 12, or 18 g of each produced a progressive increase in gas production from 234 to 1422 mL. The temperature increased from 30 degrees C at 2 g to 63 degrees C at 18 g. The time to complete the reaction decreased from 6.2 minutes at 2 g to 3.8 minutes at 18 g. The third run at the 18 g level resulted in an explosion. The results indicate that gas generation is dependent on both products.

Source: HSDB

05 · Handling and storage

Storing and handling Symclosene

Storage conditions

Store in a cool, dry, well-ventilated location. Outside or detached storage is preferred. Must be stored in a dry location on pallets arranged according to NFPA 430, Code for Storage of Liquids and Solid Oxidizers. Separate from combustibles, oxidizables, ammonia, sodium carbonate (soda ash), calcium hypochlorite, hydrogen peroxide.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

A powerful oxidizer. Violent reaction with reducing agents, combustible materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

TRICHLORO-S-TRIAZINETRIONE, DRY is an oxidizer. It reacts with combustible materials or ammonium salts, resulting in fire. It is thermally unstable, and reacts with small amounts of water to release toxic chlorine gas and explosive nitrogen trichloride. Reaction of this compound with ammonia or amines also produces nitrogen trichloride. This compound reacts explosively with calcium hypochlorite and water. [NFPA 49, 14th ed. 2010]

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Symclosene in the storage compatibility matrix →

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