A three-bed seven-step pressure swing adsorption (PSA) helium purification system has been developed exploiting PSA. It removes impurities like N2 and O2 from a ternary mixture leaving out high-purity helium from the gas mixture. In the present experimental set-up a feed gas stream containing helium (55.0 mol%), nitrogen (～35.0 mol%) and oxygen (～10.0 mol%) has been introduced into the system with predetermined pressure and flow rate. Lithium exchanged low silica X-zeolite (LiLSX) molecular sieve with an average pore diameter of 0.9–1.0 nm has been used as the adsorbing medium. Total cycle time of the PSA system was conveniently chosen to be 180 sec. The PSA system is operating successfully resulting in high-purity helium (>99.9%) with a yield of around 89%.
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