Inertization pressure purge method

One might use a gas-purge method, bubbling air or some inert gas through the sample and measuring the concentration in the air, Cair using procedures similar to that used to determine vapor pressures. The concentration in water, Cw would then be defined by the Henry s law constant as discussed in Section 2.3. Other experimental approaches to this problem have been outlined. ... 

A very common method to reduce the oxygen concentration is to draw vacuum to the apparatus or container and then to relieve it with an inert gas. This procedure is commonly called pressure purging and is repeated a number of times until the desired... 

A method by which gases, vapors, or other air contaminants are displaced from a confined space. It is accomplished so that subsequent natural ventilation will not result in the reinstatement of an undesired atmosphere. Purging is commonly accomplished by the use of a protective or inert gas (e.g., nitrogen, carbon dioxide, etc.) at a sufficient flow and positive pressure to reduce the concentration of any flammable gas, vapor, or toxic materials initially present to an acceptable level. It may also be called de-gassing. See also Inerting. 

Displacement Desorption. The temperature and pressure are maintained essentially constant, as in purge gas stripping, but instead of an inert purge the adsorbed species are displaced by a stream containing a competitively adsorbed species, as in displacement chromatography. The method is applicable to both gas and liquid systems. 

Because the majority of permeate samples are collected below atmospheric pressure, transport to the gas chromatograph or alternative analytical devices can be a challenge. This transfer is traditionally achieved by use of either an inert carrier gas or by the vacuum trap method. Transport by an inert carrier gas involves a sweep gas which is allowed to flow through the permeate chamber after sufficient sample has been collected. The product gas is carried to the gas chromatograph. The flow rate of the inert gas must be accurately known for cdculation of gas permeability coefficients (2,3). Further, the gas chromatograph must be purged with the inert gas prior to sample injection (3). 

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