High purity helium
Mineral processing 2025-04-25
| Category | Details |
|---|---|
| Purity | ≥99.9995% (6.0 grade) or ultra-high-purity ≥99.9999% (7.0 grade), with trace impurities (e.g., O₂, N₂ ≤ 0.5 ppm) |
| Key Applications | – Cryogenics: Cooling superconductors in MRI machines and particle accelerators |
| – Aerospace: Pressurizing rocket fuel tanks and purging engines | |
| – Semiconductors: Carrier gas in photolithography and etching processes | |
| – Research: Leak detection, gas chromatography, and fusion reactors | |
| – Welding: Shielding gas for non-ferrous metals (e.g., aluminum) | |
| Physical Properties | – Boiling point: -269°C (4.2 K, lowest of any gas) |
| – Low density (0.1785 g/L at STP) and high thermal conductivity | |
| – Chemically inert (non-reactive) | |
| Safety Precautions | – Non-toxic but displaces oxygen (risk of asphyxiation in confined spaces) |
| – Extreme cold hazard (liquid helium at -269°C requires cryogenic gloves) | |
| – Avoid inhalation (voice alteration risks, though temporary) | |
| Storage & Handling | – Compressed gas cylinders (e.g., 50L, 100L) at 137–200 bar pressure |
| – Dewar flasks for liquid helium (up to 10.000 liters) | |
| – Store upright in well-ventilated areas away from heat/flammables | |
| Certifications | Compliance with ISO 7291 (gaseous helium), ASTM D7673. and medical/FDA regulations for MRI use |
