Isolation of Noble Gases from Atmosphere

Isolation of Noble Gases from Atmosphere

The isolation of the Noble Gases from atmosphere involves two methods.

1.    Chemico-Physical Method:- it involves the use of some chemical regents for the removal of nitrogen and oxygen of the air and a physical method for the separation of individual noble gases from the gaseous mixture of five noble gases. There are three methods for the isolation of noble gas mixture from the atmospheric air. These are:-

a)    Ramsay and Rayleigh’s first method

b)    Ramsay and Rayleigh’s second method.

c)    Modern method- Fisher and Ringe’s method.

The first and second methods are of historical importance only and are not used now-a-days.

Modern Method-Fisher and Ringe’s method:- Air, free from moisture, is circulated through an iron retort containing calcium carbide and anhydrous calcium chloride mixture kept at 800oC.

Both oxygen and nitrogen are removed as :-

CaC2+N2--------   CaCN2   +   C

2C+O2------------2CO

2CO+O2----------2CO2

C+O2 ------------CO2

2CaC2+3CO2 ---2CaCO3+5C