HP Gas

High-Purity FC-C318 (Octafluorocyclobutance)

Properties and Classification

Appearance: Colorless and odorless gas UN Number: 1976
CAS Number: 115-25-3 Liquefied gas

* Refer to MSDS for detailed information on the properties and safety of the product.


Purity vol% Min. 99.999
Water volppm Max. 10
Acids as HF volppm Max. 1
Other fluorocarbons volppm Max. 4
N2+O2 volppm Max. 20
High-Purity FC-C318 (Octafluorocyclobutance)


Item 10L cylinder 47L cylinder
Size Inside diameter 140mm 232mm
Height (to the neck portion) 850mm 1370mm
Height (with a protective cap) * 1000mm 1520mm
Valve nozzle height (center) * 875mm 1380mm
Loading weight 5kg, 10kg 30kg, 50kg
Material Manganese steel

* Estimated values for when a standard valve is mounted on a standard cylinder. The accuracy of these values is not guaranteed.


Nozzle size Ø22 mm X 14 right-hand threads
Material BRASS

Physical & Chemical Properties

Item Unit Data
Chemical formula C4F8
Molecular weight 200.03
Boiling point °C -5.75
°F -21.5
Melting point °C -41.4
Liquid density (0°C, saturated liquid) kg/L 1.6
Gas density (0°C, saturated liquid) g/L 12.03
Specific gravity (air: 1) 6.9
Critical temperature °C 115.22
Critical pressure MPa 2.7
kg/cm2 27.5
Flammability Not applicable
Toxicity Not applicable
Latent heat of vaporization (0°C, 1013MPa) kJ/kg 246.7
Maximum permissible concentration (ACGIH) ppm
Explosive limit (in air, 35°C, 101.3kPa)

Temperature – Vapor Pressure Curve

High-Purity FC-C318 (Octafluorocyclobutance)