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

tert-Butyl hydroperoxide

tert-Butyl hydroperoxide is a liquid.

CAS 75-91-2 C4H10O2 90.12 g/mol Warning

01 · Identification

What tert-Butyl hydroperoxide is

tert-Butyl hydroperoxide is a liquid. Its molecular formula is C4H10O2 and its molecular weight is 90.12 g/mol. It boils at 89 °C, melts at -8 °C, is soluble in water.

Under the GHS it carries the signal word Warning. It is classed as flammable agents - 4th degree.

02 · Identifiers

tert-Butyl hydroperoxide identifiers and molecular data

tert-Butyl hydroperoxide CAS number and EC number

CAS number75-91-2
EC number200-915-7
Index number (CLP Annex VI)617-023-00-2

tert-Butyl hydroperoxide molecular formula and molecular weight

Molecular formulaC4H10O2
Molecular weight90.12 g/mol
Chemical class Flammable agents - 4th degree

03 · GHS classification

tert-Butyl hydroperoxide hazard classification

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

tert-Butyl hydroperoxide pictograms and signal word

Signal wordWarning

tert-Butyl hydroperoxide hazard class and category

GHS hazard classes tert-Butyl hydroperoxide falls into
Hazard class Category From code Pictogram
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 GHS08

tert-Butyl hydroperoxide hazard statements (H-codes)

Hazard statements assigned to tert-Butyl hydroperoxide
CodeHazard statement
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.

This page lists only the codes assigned to tert-Butyl hydroperoxide. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for tert-Butyl hydroperoxide

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of tert-Butyl hydroperoxi… issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

tert-Butyl hydroperoxide precautionary statements

CLP Annex VI assigns 4 precautionary statements to tert-Butyl hydroperoxide. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Response

What to do once exposure, spillage or fire has already happened.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

tert-Butyl hydroperoxide name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български трет -бутилов хидропероксид
Spanish español hidroperóxido de terc -butilo
Czech čeština terc -butylhydroperoxid
Danish dansk tert -butylhydroperoxid
German Deutsch tert -Butylhydroperoxid
Estonian eesti tert -butüülvesinikperoksiid
Greek ελληνικά tert- βουτυλο-υδροϋπεροξείδιο
English English tert -butyl hydroperoxide
French français hydroperoxyde de tert -butyle
Croatian hrvatski terc -butil hidroperoksid
Italian italiano ter -butil idroperossido
Latvian latviešu terc -butilhidroperoksīds
Lithuanian lietuvių tret -butilhidroperoksidas
Hungarian magyar tert -butil hidroperoxid
Maltese Malti idroperossidu tal-butil- tert
Dutch Nederlands tert -butylhydroperoxide
Polish polski wodoronadtlenek tert -butylu
Portuguese português hidroperóxido de terc -butilo
Romanian română Hidroperoxid de terț -butil
Slovak slovenčina terc -butyl-hydroperoxid
Slovenian slovenščina tert -butil hidroperoksid
Finnish suomi tert -butyylihydroperoksidi
Swedish svenska tert -butylhydroperoxid

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

tert-Butyl hydroperoxide GHS label elements

Everything CLP Annex VI fixes for tert-Butyl hydroperoxide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS08 Health hazard pictogram

Warning

tert-Butyl hydroperoxide

  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Obtain special instructions before use.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF exposed or concerned:
  • Get medical advice/attention.

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open tert-Butyl hydroperoxide in the GHS label constructor →

07 · Physical and chemical properties

tert-Butyl hydroperoxide 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.

tert-Butyl hydroperoxide boiling point

Property Value Conditions Source
Boiling point 89 °C (192.2 °F) decomposes, decomposes HSDB
88.89 °C (192 °F) decomposes, at 760 mmHg CAMEO
35 °C (95 °F) at 20 mmHg (reduced pressure) HSDB

tert-Butyl hydroperoxide melting point

Property Value Conditions Source
Melting point -8 °C (17.6 °F) HSDB
6 °C (42.8 °F) HSDB
-7.78 °C (18 °F) CAMEO

tert-Butyl hydroperoxide density

Property Value Conditions Source
Density 0.93 g/cm³ ICSC
0.896 g/cm³ at 20 °C HSDB
0.88 g/cm³ at 25 °C CAMEO

tert-Butyl hydroperoxide solubility

Property Value Conditions Source
Solubility Soluble in water HSDB
Moderately soluble in water HSDB
Slightly soluble in water HSDB

tert-Butyl hydroperoxide vapor pressure

Property Value Conditions Source
Vapor pressure 23.0269 mmHg at 20 °C ICSC
3.07 mmHg at 20 °C DOE PAC
5.46 mmHg at 25 °C HSDB

tert-Butyl hydroperoxide flash point

Property Value Conditions Source
Flash point 26.67 °C (80 °F) CAMEO
43 °C (109.4 °F) ICSC
26.67 °C (80 °F) below this value HSDB

tert-Butyl hydroperoxide autoignition temperature

Property Value Conditions Source
Autoignition temperature 238 °C (460.4 °F) ICSC

tert-Butyl hydroperoxide lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) 5 % by volume ICSC
May explode on heating. From table HSDB
Moderately explosive; may explode during distillation. HSDB

tert-Butyl hydroperoxide upper explosive limit (UEL)

Property Value Conditions Source
Upper explosive limit (UEL) 10 % by volume ICSC

tert-Butyl hydroperoxide vapor density

Property Value Conditions Source
Vapor density 2.07 (air = 1) HSDB
3.1 (air = 1) ICSC

tert-Butyl hydroperoxide odor threshold

Property Value Conditions Source
Odor threshold Odor Threshold Low: 0.05 [ppm] Haz-Map

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

08 · Fire and explosion

tert-Butyl hydroperoxide fire and explosion behaviour

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.

tert-Butyl hydroperoxide fire potential

Very dangerous fire hazard when exposed to heat or flame, or by spontaneous chemical reaction such as with reducing materials.

Source: Hazardous Substances Data Bank (HSDB)

09 · Handling and storage

tert-Butyl hydroperoxide storage and handling

tert-Butyl hydroperoxide safe storage

Fireproof. Separated from combustible substances and reducing agents. Cool. Inspect container frequently to identify bulging and leaking.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

tert-Butyl hydroperoxide storage conditions

Store in original container. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature 2 - 8 °C

Source: Hazardous Substances Data Bank (HSDB)

tert-Butyl hydroperoxide incompatible materials

Violent reactions with traces of acids. Concentrated solutions may ignite spontaneously on contact with molecular sieve. Mixtures with transition metal salts may react vigorously and release oxygen.

Source: Hazardous Substances Data Bank (HSDB)

tert-Butyl hydroperoxide reactivity

Most alkyl monohydroperoxides, such as TERT-BUTYL HYDROPEROXIDE, are liquid. The explosivity of the lower members (e.g., methyl hydroperoxide or possibly traces of the dialkyl peroxides) decreasing with increasing chain length and branching, [Bretherick 2nd ed. 1979 p. 10]. Though relatively stable explosions have been caused by distillation to dryness [Milas, JACS, 1946 68 205] or attempted distillation at atmospheric pressure (Castrantas 1965 p 15). Very soluble in organic solvents and alkali metal hydroxide solutions. Combustible and a moderate fire risk [Hawley].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check tert-Butyl hydroperoxide in the storage compatibility matrix →

10 · Questions

tert-Butyl hydroperoxide — frequently asked questions

What is the CAS number of tert-Butyl hydroperoxide?

The CAS number of tert-Butyl hydroperoxide is 75-91-2. Its EC number is 200-915-7.

What is the chemical formula of tert-Butyl hydroperoxide?

The molecular formula of tert-Butyl hydroperoxide is C4H10O2 and its molecular weight is 90.12 g/mol.

What does a tert-Butyl hydroperoxide label have to show?

Under CLP Annex VI the label for tert-Butyl hydroperoxide carries the pictogram Health hazard and the signal word is Warning.

Is tert-Butyl hydroperoxide flammable?

CLP Annex VI assigns tert-Butyl hydroperoxide no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it. The flash point reported for it is 26.67 °C (80 °F) (CAMEO).

Is tert-Butyl hydroperoxide a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for tert-Butyl hydroperoxide. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health.

What is the boiling point of tert-Butyl hydroperoxide?

The boiling point reported for tert-Butyl hydroperoxide is 89 °C (192.2 °F), decomposes, decomposes (HSDB).

What is the melting point of tert-Butyl hydroperoxide?

The melting point reported for tert-Butyl hydroperoxide is -8 °C (17.6 °F) (HSDB).

How should tert-Butyl hydroperoxide be stored?

Store in original container. Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature 2 - 8 °C (Hazardous Substances Data Bank (HSDB))

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