Antifreeze - Ethylene Glycol vs. Propylene Glycol
Comparing ethylene glycol and propylene glycol antifreeze properties.
Characteristics of ethylene glycol and propylene glycol as antifreeze:
| Property | Ethylene Glycol | Propylene Glycol | Comments |
|---|---|---|---|
| Freeze point depression | more effective | less effective | More antifreeze is needed of propylene glycol to achieve the same freeze point |
| Heat transfer efficiency/capability | better | less | Ethylene glycol has superior heat transfer efficiency due to lower viscosity - but more fluid must be circulated to transfer the same amount of energy since Propylene glycol has higher specific heat. |
| Viscosity | lower | higher | Propylene glycol increases major head loss in the systems. Pumps head increased. |
| Flammability | low | low | |
| Chemical oxygen demand | low | higher | |
| Biodegrading | degrades in 10 - 30 days | needs more than 20 - 30 days to degrade | |
| Carcinogenic | no | no | A carcinogen is any substance or agent that promotes cancer |
| Toxic | High level of acute when taken orally, targets the kidneys | Lower level of acute | Ethylene glycol should never be used in any drinking water or food processing system |
| Skin irritant | low | low | Propylene glycol is used in small amounts in cosmetics |
- more about ethylene glycol
- more about propylene glycol
