Summary. Glycerine is not hazardous and not transport-regulated, but it is thick (954 cP at 25 C), melts near 17.8 C and is hygroscopic. Store closed at 15-30 C, warm gently to about 25 C if solid, and reseal after each draw-off.
Know the material before you handle it
Glycerine (glycerol, CAS 56-81-5) is a clear, colourless, syrupy liquid, miscible with water and ethanol. The grade we supply on the glycerine page is Refined Glycerine (IP), packed in 250 kg HDPE drums and dispatched from our Redhills warehouse in Chennai. Its handling questions come from three properties: viscosity, a melting point close to room temperature, and hygroscopy.
| Property | Value |
|---|---|
| Melting / freezing point | 17.8 C |
| Viscosity | 954 cP at 25 C |
Source: SPC Safety Data Sheet sections 5, 7 and 9. Flash point (160 C), boiling point (290 C, decomposes) and the 15 - 30 C storage range are on the product page. Specification limits for the IP grade are on the data sheet (SPC-TDS-OLE-001).
Cold-weather thickening and crystallising
Glycerine melts near 17.8 C. In a cool or air-conditioned store or vehicle (general observation), pure glycerine can become very viscous or partly solid. This is a physical change, not a quality fault; the Safety Data Sheet states that gentle warming to about 25 C restores the liquid state.
How to warm a thickened drum
The Safety Data Sheet supports only the statement above. The steps below are general practice, not an SPC or SDS instruction; follow your site safety procedure.
- Move the closed drum into a warmer room and allow it to equilibrate. This is the gentlest method and often enough.
- If you need to speed it up, avoid a naked flame or a hot spot. Glycerine decomposes toward its boiling point and can degrade when overheated (general chemistry).
- Keep the drum closed while warming so warm glycerine does not draw in moist air.
- Once liquid, mix gently before sampling so the contents are uniform.
Hygroscopy: why closed means closed
Glycerine is hygroscopic: it draws water from humid air. Our IP specification limits water to 2.0 % w/w max, and the batch Certificate of Analysis shows the lot result. If a drum is left open in humid air, the water content can rise, which changes density, refractive index and viscosity and can affect your formulation. Practical steps (general practice):
- Keep drums tightly closed when not in use, and reseal after every draw-off.
- Draw off what you need rather than leaving a part-used drum open to the air.
- Use a clean, dry transfer hose and dry receiving vessels.
- Record the opening date on the drum if you take several weeks to use it.
Storage and compatibility
The TDS safety line summarises storage: non-hazardous hygroscopic liquid, store closed, away from moisture and oxidisers. The Safety Data Sheet gives a storage range of about 15 - 30 C. Inspect drums for leakage or damage as a matter of general practice.
Hazard status in plain terms
The Safety Data Sheet states glycerine is not classified as hazardous under GHS, with no signal word and no pictogram, and that it is not regulated for road, sea or air transport (no UN number). It is still a combustible liquid with a flash point of about 160 C, so fire-safety planning applies at high temperature. As general practice, wash hands after handling and read the full Safety Data Sheet before use.
Moving a viscous liquid: general pumping tips
The following points are general engineering practice, not SPC specifications. A liquid of around 954 cP is far more resistant to flow than water, so the equipment choices matter.
- Pump type: positive-displacement pumps are generally preferred over centrifugal pumps for thick liquids.
- Line size: use short, wide-bore suction lines to limit pressure loss.
- Temperature: viscosity falls steeply as glycerine warms, so a modestly warmed product pumps far more easily.
- Dilution: water lowers viscosity sharply, which is one reason water pick-up changes behaviour in the line.
- Emptying a drum: allow time for the contents to drain; tilting or using a drum pump with a suitable dip tube helps. Rinse equipment with warm water, since glycerine is miscible with it.
Common problems and quick checks
| Symptom | Likely cause | First check |
|---|---|---|
| Drum contents thick or solid | Storage below about 18 C | Room temperature; warm gently to about 25 C |
| Density or refractive index lower than expected | Water pick-up after opening | Whether the drum was left open; compare to the batch Certificate of Analysis |
| Slow transfer | High viscosity | Product temperature, pump type, hose bore |
| Discolouration after warming | Localised overheating | Heating method; avoid hot spots |
Source: causes and checks are general practice, not SPC specifications.
Choosing the grade, then the handling plan
Handling is broadly the same across grades, but documents differ. Before you order, decide which grade your specification names; our guide to reading a glycerine Certificate of Analysis walks through the IP data sheet and the batch certificate. For general rules that apply across chemicals, see chemical storage and handling basics for industrial buyers.
Ordering
Supreme Petro Chemicals is an importer and distributor in Chennai; we supply glycerine and do not manufacture it. Call or WhatsApp +91 86087 80096 with the grade, quantity, pack (250 kg HDPE drums), delivery location and the documents you need. We quote within 4 working hours, and a batch Certificate of Analysis is supplied with every delivery.