Substance profile
Dipotassium peroxodisulphate
Dipotassium peroxodisulphate is colorless, triclinic crystals and is odorless.
01 · Identification
What Dipotassium peroxodisulphate is
Dipotassium peroxodisulphate is colorless, triclinic crystals and is odorless. Its molecular formula is K2O8S2 and its molecular weight is 270.33 g/mol.
Under the GHS it carries the signal word Danger. It is classed as reactive agents - 1st degree.
02 · Identifiers
Dipotassium peroxodisulphate identifiers and molecular data
Dipotassium peroxodisulphate CAS number and EC number
Dipotassium peroxodisulphate molecular formula and molecular weight
Other names for Dipotassium peroxodisulphate
- potassium persulphate
03 · GHS classification
Dipotassium peroxodisulphate hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Dipotassium peroxodisulphate pictograms and signal word
Dipotassium peroxodisulphate hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Oxidising liquids or Oxidising solids | Category 2 or 3 | H272 | GHS03 |
| Acute toxicity - oral GHS chapter 3.1 | Category 4 | H302 | GHS07 |
| Skin corrosion/irritation GHS chapter 3.2 | Category 2 | H315 | GHS07 |
| Serious eye damage/eye irritation GHS chapter 3.3 | Category 2A | H319 | GHS07 |
| Respiratory sensitisation GHS chapter 3.4 | Category 1 or 1A or 1B | H334 | GHS08 |
| Skin sensitisation GHS chapter 3.4 | Category 1 or 1A or 1B | H317 | GHS07 |
| Specific target organ toxicity - single exposure GHS chapter 3.8 | Category 3 | H335 | GHS07 |
Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.
Dipotassium peroxodisulphate hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H272 | May intensify fire; oxidiser. |
| H302 | Harmful if swallowed. |
| H335 | May cause respiratory irritation. |
| H315 | Causes skin irritation. |
| H319 | Causes serious eye irritation. |
| H334 | May cause allergy or asthma symptoms or breathing difficulties if inhaled. |
| H317 | May cause an allergic skin reaction. |
This page lists only the codes assigned to Dipotassium peroxodisulpha…. 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 Dipotassium peroxodisulpha…
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 Dipotassium peroxodisu… 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
Dipotassium peroxodisulphate precautionary statements
CLP Annex VI assigns 16 precautionary statements to Dipotassium peroxodisulpha…. 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.
Prevention
What to do before and during handling so the hazard never happens.
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
Dipotassium peroxodisulphate 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 | дикалиев пероксодисулфат калиев персулфат |
| Spanish español | Peroxodisulfato de dipotasio persulfato de potasio |
| Czech čeština | dikalium-peroxodisulfát peroxodisíran draselný |
| Danish dansk | dikaliumperoxodisulfat kaliumpersulfat |
| German Deutsch | Dikaliumperoxodisulfat Kaliumpersulfat |
| Estonian eesti | dikaaliumperoksodisulfaat kaaliumpersulfaat |
| Greek ελληνικά | υπεροξοδιθειικό δικάλιο υπερθειικό κάλιο |
| English English | dipotassium peroxodisulphate potassium persulphate |
| French français | peroxodisulfate de dipotassium persulfate de potassium |
| Croatian hrvatski | dikalijev peroksodisulfat kalijev persulfat |
| Italian italiano | perossodisolfato di dipotassio potassium persulphate |
| Latvian latviešu | dikālija peroksidisulfāts kālija persulfāts |
| Lithuanian lietuvių | dikalio peroksodisulfatas kalio peroksosulfatas |
| Hungarian magyar | dikálium-peroxodiszulfát kálium-perszulfát |
| Maltese Malti | perossodisulfat tad-dipotassju persulfat tal-potassju |
| Dutch Nederlands | dikaliumperoxodisulfaat kaliumpersulfaat |
| Polish polski | peroksodisiarczan(VI) dipotasu nadtlenodisiarczan(VI) dipotasu |
| Portuguese português | peroxodissulfato de dipotássio persulfato de potássio |
| Romanian română | peroxidisulfat de dipotasiu persulfat de potasiu |
| Slovak slovenčina | peroxodisíran draselný kálium-persulfát |
| Slovenian slovenščina | dikalijev peroksodisulfat kalijev persulfat |
| Finnish suomi | dikaliumperoksodisulfaatti kaliumpersulfaatti |
| Swedish svenska | dikaliumperoxodisulfat kaliumpersulfat |
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
Dipotassium peroxodisulphate GHS label elements
Everything CLP Annex VI fixes for Dipotassium peroxodisulpha…, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Dipotassium peroxodisulphate
- May intensify fire; oxidiser.
- Harmful if swallowed.
- May cause respiratory irritation.
- Causes skin irritation.
- Causes serious eye irritation.
- May cause allergy or asthma symptoms or breathing difficulties if inhaled.
- May cause an allergic skin reaction.
- Avoid breathing dust/fume/gas/mist/vapours/spray.
- Wash … thoroughly after handling.
- Do not eat, drink or smoke when using this product.
- Contaminated work clothing should not be allowed out of the workplace.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF ON SKIN:
- IF IN EYES:
- Call a POISON CENTER/doctor/… if you feel unwell.
- Get medical advice/attention.
- Rinse mouth.
- If skin irritation occurs:
- If skin irritation or rash occurs:
- If eye irritation persists:
- Remove contact lenses, if present and easy to do. Continue rinsing.
- Wash with plenty of water/…
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Dipotassium peroxodisulpha… in the GHS label constructor →
07 · Physical and chemical properties
Dipotassium peroxodisulphate 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.
Dipotassium peroxodisulphate density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 2.477 g/cm³ | HSDB | |
| 2.5 g/cm³ | ICSC | ||
| 2.477 g/cm³ | at 25 °C | DOE PAC |
Dipotassium peroxodisulphate solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | INSOL IN ALCOHOL | HSDB | |
| 5.2 G IN 100 CC OF HOT WATER @ 20 °C | at 20 °C | HSDB | |
| Solubility in water, g/100ml at 20 °C: 5.2 | at 20 °C | ICSC |
Dipotassium peroxodisulphate vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 2.48 (air = 1) | OSHA |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
08 · Fire and explosion
Dipotassium peroxodisulpha… 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.
Dipotassium peroxodisulphate fire potential
POTASSIUM PERSULFATE PLUS A LITTLE POTASSIUM HYDROXIDE & WATER IGNITED POLYTHENE (POLYETHYLENE) LINER OF CONTAINER BY SIMULTANEOUS RELEASE OF HEAT & OXYGEN.
Source: Hazardous Substances Data Bank (HSDB)
09 · Handling and storage
Dipotassium peroxodisulphate storage and handling
Dipotassium peroxodisulphate safe storage
Cool. Dry. Well closed. Separated from combustible substances, reducing agents and strong bases.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Dipotassium peroxodisulphate storage conditions
Keep containers closed and store in cool dark places.
Source: Hazardous Substances Data Bank (HSDB)
Dipotassium peroxodisulphate incompatible materials
POTASSIUM PERSULFATE PLUS A LITTLE POTASSIUM HYDROXIDE & WATER IGNITED POLYTHENE (POLYETHYLENE) LINER OF CONTAINER BY SIMULTANEOUS RELEASE OF HEAT & OXYGEN.
Source: Hazardous Substances Data Bank (HSDB)
Dipotassium peroxodisulphate reactivity
POTASSIUM PERSULFATE is an oxidizing agent. Noncombustible but accelerates the burning of combustible material. Potassium persulfate plus a little potassium hydroxide and water released sufficient heat and oxygen to ignite a polythene (polyethylene) liner in a container. [MCA Case History 1155. 1955].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Dipotassium peroxodisulph… in the storage compatibility matrix →
10 · Transport
Dipotassium peroxodisulphate UN number and transport classification
Transport classification is a separate system from the GHS classification above. It decides how a package is marked and how a load may be carried; it does not follow from the workplace label, and the workplace label does not follow from it. The entries below are linked by CAS number, never by name.
Dipotassium peroxodisulphate under UN 1492 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| POTASSIUM PERSULPHATE | 5.1 | O2 | III | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 5.1 is “Oxidizing substances” (ADR 2.1.1.1).
United States · 49 CFR 172.101 Hazardous Materials Table
| Proper shipping name (column 2) | Class or division | PG | Labels (column 6) |
|---|---|---|---|
| Potassium persulfate | 5.1 | III | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 5.1 is “Oxidizer” (49 CFR 173.2).
11 · Questions
Dipotassium peroxodisulphate — frequently asked questions
What is the CAS number of Dipotassium peroxodisulphate?
The CAS number of Dipotassium peroxodisulphate is 7727-21-1. Its EC number is 231-781-8.
What is the chemical formula of Dipotassium peroxodisulphate?
The molecular formula of Dipotassium peroxodisulphate is K2O8S2 and its molecular weight is 270.33 g/mol.
What does a Dipotassium peroxodisulphate label have to show?
Under CLP Annex VI the label for Dipotassium peroxodisulphate carries the pictograms Flame over circle, Health hazard and Exclamation mark and the signal word is Danger.
Is Dipotassium peroxodisulphate flammable?
CLP Annex VI assigns Dipotassium peroxodisulphate 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.
Is Dipotassium peroxodisulphate a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Dipotassium peroxodisulphate. 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.
How should Dipotassium peroxodisulphate be stored?
Keep containers closed and store in cool dark places. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Dipotassium peroxodisulpha…
Keep going: substances starting with D, or search the whole database by name, CAS number, pictogram or signal word.