Substance profile
Morpholine
Morpholine is a colorless liquid with a characteristic amine odor.
01 · Identification
What Morpholine is
Morpholine is a colorless liquid with a characteristic amine odor. Its molecular formula is C4H9NO and its molecular weight is 87.12 g/mol. It boils at 128 °C, melts at -4.8 °C.
Under the GHS it carries the signal word Danger. It is classed as corrosives.
02 · Identifiers
Morpholine identifiers and molecular data
Morpholine CAS number and EC number
Morpholine molecular formula and molecular weight
03 · GHS classification
Morpholine hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Morpholine pictograms and signal word
Morpholine hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Flammable liquids GHS chapter 2.6 | Category 3 | H226 | GHS02 |
| Acute toxicity - oral GHS chapter 3.1 | Category 4 | H302 | GHS07 |
| Acute toxicity - dermal GHS chapter 3.1 | Category 4 | H312 | GHS07 |
| Acute toxicity - inhalation GHS chapter 3.1 | Category 4 | H332 | GHS07 |
| Skin corrosion/irritation GHS chapter 3.2 | Category 1A or 1B or 1C | H314 | GHS05 |
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.
Morpholine hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H226 | Flammable liquid and vapour. |
| H332 | Harmful if inhaled. |
| H312 | Harmful in contact with skin. |
| H302 | Harmful if swallowed. |
| H314 | Causes severe skin burns and eye damage. |
This page lists only the codes assigned to Morpholine. 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 Morpholine
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 Morpholine 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
Morpholine precautionary statements
CLP Annex VI assigns 17 precautionary statements to Morpholine. 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
Morpholine 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 | морфолин |
| Spanish español | Morfolina |
| Czech čeština | morfolin |
| Danish dansk | morpholin |
| German Deutsch | Morpholin |
| Estonian eesti | morfoliin |
| Greek ελληνικά | μορφολίνη |
| English English | morpholine |
| French français | morpholine |
| Croatian hrvatski | morfolin |
| Italian italiano | morfolina |
| Latvian latviešu | morfolīns |
| Lithuanian lietuvių | morfolinas |
| Hungarian magyar | morfolin |
| Maltese Malti | morfolina |
| Dutch Nederlands | morfoline |
| Polish polski | morfolina |
| Portuguese português | morfolina |
| Romanian română | morfolină |
| Slovak slovenčina | morfolín |
| Slovenian slovenščina | morfolin |
| Finnish suomi | morfoliini |
| Swedish svenska | morfolin |
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
Morpholine GHS label elements
Everything CLP Annex VI fixes for Morpholine, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Morpholine
- Flammable liquid and vapour.
- Harmful if inhaled.
- Harmful in contact with skin.
- Harmful if swallowed.
- Causes severe skin burns and eye damage.
- Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
- Keep container tightly closed.
- Use explosion-proof [electrical/ventilating/lighting/…] equipment.
- Use only non-sparking tools.
- Do not breathe dust/fume/gas/mist/vapours/spray.
- Do not eat, drink or smoke when using this product.
- Use only outdoors or in a well-ventilated area.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF SWALLOWED:
- IF ON SKIN:
- IF INHALED:
- Immediately call a POISON CENTER/doctor/…
- Call a POISON CENTER/doctor/… if you feel unwell.
- Rinse mouth.
- Do NOT induce vomiting.
- Wash with plenty of water/…
- Store in a well-ventilated place.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Morpholine in the GHS label constructor →
07 · Health hazards
Morpholine health hazards and exposure limits
Morpholine hazard summary
Liver damage is prominent in animals exposed to high concentrations. Skin, eye, and respiratory irritation, but no chronic health effects, were reported after occupational exposure. [ACGIH] Corrosive to skin; [Quick CPC] A corrosive substance that can cause pulmonary edema; [ICSC]
Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
Morpholine carcinogenicity classification
Evaluation: No epidemiological data relevant to the carcinogenicity of morpholine were available. There is inadequate evidence in experimental animals for the carcinogenicity of morpholine. Overall evaluation: Morpholine is not classifiable as to its carcinogenicity to humans (Group 3).
Source: Hazardous Substances Data Bank (HSDB)
An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.
Morpholine occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | 20.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| PEL | 20 ppm (70 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| PEL | TWA 20 ppm (70 mg/m3) [skin] See Appendix G | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | 20 ppm (70 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | 30 ppm (105 mg/m³) | Occupational Safety and Health Administration (OSHA) |
| REL | TWA 20 ppm (70 mg/m3) ST 30 ppm (105 mg/m3) [skin] | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | 1400 ppm ; Based on 10% of the lower explosive limit. (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | 1400.0 [ppm] | Haz-Map, Information on Hazardous Chemicals and Occupational Diseases |
| IDLH | 1400 ppm | Occupational Safety and Health Administration (OSHA) |
These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.
08 · Physical and chemical properties
Morpholine 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.
Morpholine boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 128 °C (262.4 °F) | HSDB | |
| 128.89 °C (264 °F) | NIOSH | ||
| 128.89 °C (264 °F) | at 760 mmHg | CAMEO |
Morpholine melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | -4.8 °C (23.4 °F) | HSDB | |
| -5 °C (23 °F) | NIOSH | ||
| -4.89 °C (23.2 °F) | CAMEO |
Morpholine density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.007 g/cm³ | NIOSH | |
| 1.007 g/cm³ | at 20 °C | HSDB | |
| 0.9994 g/cm³ | at 20 °C | HSDB |
Morpholine solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | Solluble in organic solvents | HSDB | |
| In water, 1.00X10+6 mg/L | miscible | HSDB |
Morpholine vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 6 mmHg | NIOSH | |
| 6.6 mmHg | at 20 °C | CAMEO | |
| 10.1 mmHg | at 25 °C | HSDB |
Morpholine flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 35 °C (95 °F) | closed cup | HSDB |
| 36.67 °C (98 °F) | NIOSH | ||
| 37.78 °C (100 °F) | CAMEO |
Morpholine autoignition temperature
| Property | Value | Conditions | Source |
|---|---|---|---|
| Autoignition temperature | 310 °C (590 °F) | anhydrous | HSDB |
| 310 °C (590 °F) | CAMEO |
Morpholine lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | 1.4 % by volume | HSDB |
Morpholine upper explosive limit (UEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Upper explosive limit (UEL) | 11.2 % by volume | HSDB |
Morpholine vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 3 (air = 1) | HSDB |
Morpholine odor threshold
| Property | Value | Conditions | Source |
|---|---|---|---|
| Odor threshold | Air: 0.01 ppm (v/v) | HSDB | |
| Odor Threshold Low: 0.01 [ppm] | Haz-Map |
Morpholine critical temperature and pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Critical temperature and pressure | 344 °C (651.2 °F) | HSDB |
Morpholine corrosivity
| Property | Value | Conditions | Source |
|---|---|---|---|
| Corrosivity | Corrosive to metals | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Fire and explosion
Morpholine 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.
Morpholine fire potential
A very dangrous fire hazard when exposed to flame, heat, or oxidizers.
Source: Hazardous Substances Data Bank (HSDB)
Solubility
Immiscible with concn sodium hydroxide soln; miscible with acetone, benzene, ether, castor oil, methanol, ethanol, ethylene glycol, 2-hexanone, linseed oil, turpentine, pine oil; miscible with water with evolution of some heat
Source: HSDB
Odor
The absolute and recognition threshold odor index of 101 petrochemicals /were tested/ using a trained panel. During a 20 min exposure, 0.036 mg morpholine/cu m was recognized by 50% of the panel and 0.5 mg morpholine/cu m by all of the panel (giving an odor index of 65.9). It was described as an unpleasant fishy smell.
Source: HSDB
10 · Handling and storage
Morpholine storage and handling
Morpholine safe storage
Fireproof. Separated from strong oxidants and acids. Dry.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Morpholine storage conditions
Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Morpholine must be stored to avoid contact with strong acids, such as nitric acid, and strong oxidizers, such as chlorine dioxide, bromine, nitrates, and permanganates, since violent reactions occur.
Source: Hazardous Substances Data Bank (HSDB)
Morpholine incompatible materials
Violent reaction and fire may result when the product is mixed with oxidizing agents, such as perchlorates, nitrates, permanganates, chromates, nitric acid, halogens, peroxides, and some cleaning solutions containing acids.
Source: Hazardous Substances Data Bank (HSDB)
Morpholine reactivity
MORPHOLINE neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. May generate hydrogen, a flammable gas, in combination with strong reducing agents such as hydrides. Sensitive to moisture. Reacts readily with oxidizing agents (NTP, 1992).
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Morpholine in the storage compatibility matrix →
11 · Transport
Morpholine 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.
Morpholine under UN 2054 — shipping name, class and packing group
Europe · ADR 2025, Table A
| Proper shipping name (3.1.2) | Class | Classification code | PG | Labels (column 5) |
|---|---|---|---|---|
| MORPHOLINE | 8 | CF1 | I | |
Source: ADR 2025, Table A of Chapter 3.2 · ECE/TRANS/352 Vol. I (UNECE). Class 8 is “Corrosive 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) |
|---|---|---|---|
| Morpholine | 8 | I | |
Source: 49 CFR 172.101 Hazardous Materials Table · eCFR, revision 2026-08-03. Class 8 is “Corrosive material” (49 CFR 173.2).
12 · Questions
Morpholine — frequently asked questions
What is the CAS number of Morpholine?
The CAS number of Morpholine is 110-91-8. Its EC number is 203-815-1.
What is the chemical formula of Morpholine?
The molecular formula of Morpholine is C4H9NO and its molecular weight is 87.12 g/mol.
What does a Morpholine label have to show?
Under CLP Annex VI the label for Morpholine carries the pictograms Flame, Corrosion and Exclamation mark and the signal word is Danger.
Is Morpholine flammable?
Yes. CLP Annex VI assigns Morpholine H226 — flammable liquid and vapour. The flash point reported for it is 35 °C (95 °F), closed cup (HSDB).
Is Morpholine a carcinogen?
CLP Annex VI records no harmonised carcinogenicity classification for Morpholine. 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. IARC places it in Group 3: not classifiable as to its carcinogenicity to humans.
What is the exposure limit for Morpholine?
The US occupational exposure limit reported for Morpholine is 20.0 [ppm] (Haz-Map, Information on Hazardous Chemicals and Occupational Diseases). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.
What is the boiling point of Morpholine?
The boiling point reported for Morpholine is 128 °C (262.4 °F) (HSDB).
What is the melting point of Morpholine?
The melting point reported for Morpholine is -4.8 °C (23.4 °F) (HSDB).
How should Morpholine be stored?
CLP Annex VI assigns Morpholine the storage statement P403. Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. Morpholine must be stored to avoid contact with strong acids, such as nitric acid, and strong oxidizers, such as chlorine dioxide, bromine, nitrates, and permanganates, since violent reactions occur. (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Morpholine
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