R152a (also known as Difluoroethane) is a hydrofluorocarbon (HFC) commonly used as a refrigerant and aerosol propellant. Unlike the pentanes previously discussed, R152a is a gas at standard temperature and pressure.
General Characteristics
- Chemical Formula: C2H4F2
- Appearance: Colorless and odorless gas.
- Environmental Profile: It has Zero Ozone Depletion Potential (ODP) and a relatively low Global Warming Potential (GWP) of approximately 124, making it a more eco-friendly alternative to R134a.
- Flammability: Classified as A2 (Slightly Flammable) by ASHRAE. It is more flammable than R134a but less so than hydrocarbons like Isopentane.
- Solubility: Slightly soluble in water; highly soluble in organic solvents and ether.
Technical Specifications (Typical)
- Molecular Weight: 66.05 g/mol
- Boiling Point (at 1 atm): -25°C (-13°F)
- Critical Temperature: 113.3°C (235.9°F)
- Critical Pressure: 4.52 MPa (45.2 bar)
- Liquid Density (at 25°C): 0.90 g/cm³
- Vapor Pressure (at 25°C): 596 kPa (5.96 bar)
- Auto-ignition Temperature: 455°C (851°F)
- Purity: Typically ≥ 99.9% for refrigeration grade.
Primary Industrial Uses
- Refrigerant: Used in domestic refrigeration and mobile air conditioning systems, often as a component in refrigerant blends.
- Aerosol Propellant: Widely used in “canned air” (dusters), hairsprays, and deodorants due to its low environmental impact.
- Blowing Agent: Used in the production of extruded polystyrene (XPS) foam for insulation boards.