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

Pentachlorophenol

Pentachlorophenol is a white monoclinic, crystalline solid with a phenolic odor.

CAS 87-86-5 C6HCl5O 266.3 g/mol Danger

01 · Identification

What Pentachlorophenol is

Pentachlorophenol is a white monoclinic, crystalline solid with a phenolic odor. Its molecular formula is C6HCl5O and its molecular weight is 266.3 g/mol. It boils at 310 °C, melts at 174 °C, is slightly soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number87-86-5
EC number201-778-6
Index number604-002-00-8
Molecular formulaC6HCl5O
Molecular weight266.3 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

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 Pentachlorophenol
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H330 Fatal if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P260, P264, P270, P271, P273, P280, P301, P302, P304, P305, P308, P310, P313, P330, P332, P337, P338, P352, P391, P501

03 · Physical and chemical properties

Pentachlorophenol 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
Boiling point 309.5 °C (589.1 °F) range, midpoint shown HSDB
309.44 °C (589 °F) range, midpoint shown, at 760 mmHg CAMEO
308.89 °C (588 °F) decomposes NIOSH
Melting point 174 °C (345.2 °F) HSDB
190 °C (374 °F) NIOSH
191.11 °C (376 °F) CAMEO
Density 1.978 g/cm³ HSDB
1.98 g/cm³ NIOSH
Solubility Slightly soluble in ligroin; very soluble in diethyl ether HSDB
Sol in dilute alkali, carbitol, cellosolve HSDB
Soluble in most organic solvents, for example acetone 215 g/L at 20 °C. Slightly soluble in ... parafins. at 20 °C HSDB
Vapor pressure 0.00011 mmHg at 20 °C CAMEO
0.00011 mmHg at 25 °C HSDB
0.0001 mmHg at 25 °C NIOSH
Autoignition temperature Not flammable (USCG, 1999) CAMEO
Lower explosive limit (LEL) Noncombustible Solid NIOSH
Vapor density 9.2 (air = 1) HSDB
Odor threshold Odor thresholds for PCP soln at 30 deg and 60 °C were 857 and 12,000 ug/l, respectively. HSDB
Detection: 1.6 mg/l. HSDB
Corrosivity Noncorrosive in absence of moisture HSDB

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

04 · Handling and storage

Storing and handling Pentachlorophenol

Storage conditions

Where possible, automatically transfer material from drums or other storage containers to process containers. Sources of ignition such as smoking and open flames are prohibited where this chemical is handled, used, or stored. Metal containers involving the transfer of this chemical should be grounded and bonded. A regulated, marked area should be established where this chemical is handled, used or stored ...

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Contact with strong oxidizers may cause fires or explosions.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PENTACHLOROPHENOL may react with strong oxidizing agents. Incompatible with strong bases, acid chlorides and acid anhydrides. Forms salts with alkaline metals. Solutions in oil cause natural rubber to deteriorate, but synthetic rubber may be used in equipment and for protective clothing (NTP, 1992).

Source: CAMEO Chemicals

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

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