Preparation method of helium
1. Condensation method: Natural gas is used to extract helium. Condensation method is used in industry. The process includes pretreatment and purification of natural gas, preparation of crude helium and helium refining, etc. 99.99% pure helium is produced.
2. Air separation method: The crude helium and neon mixture gas is generally extracted from the air device by a separate condensation method, and pure helium and neon mixture gas are prepared from the crude helium and neon mixture gas, and 99.99% pure helium gas is obtained by separation and purification .
3. Hydrogen liquefaction method: The industry adopts hydrogen liquefaction method to extract helium from synthetic ammonia tail gas. The process of this method is to remove nitrogen by low temperature adsorption and rectification to obtain crude helium plus oxygen for catalytic hydrogen removal and purification of helium, and produce 99.99% pure helium.
4. High-purity helium method: 99.99% pure helium is further purified by activated carbon to obtain 99.9999% high-purity helium.