Simpler purification of helium

Energy per Ion Pair Measurements in Pure Helium and Helium Mixtures

“…This system used titanium chips at 800°C to remove nitrogen, and hopcalite (a mixture of copper and manganese and their oxides) at 400°C to trap oxygen as copper oxide, and to oxidise hydrogen to water and carbon monoxide to carbon dioxide. Later work byBourke (1965) showed that the titanium trap was unnecessary if cooled molecular sieve was used to trap nitrogen.In view of this, and to avoid the difficulties associated with high temperature systems, a titanium trap was not used in the present work. Design of purification and gas entry systems The purification traps and pipework were constructed of stainless steel, using a commercial coupling system to ensure that the arrangement could easily be changed for specific needs.…”

Gas Chromatography

“…Carrier gases have received little attention in the literature during the past three years. However, there had been described a process for purifying helium which seems to be applicable to the preparation of this gas for high sensitivity ionization type detectors (80). The carrier gas is usually considered a minor factor in determining the partition coefficient, but Sewell and Stock (559) have shown that carrier gases, such as nitrogen, can affect the solubility of a gas or vapor by altering its fugacity.…”

Standardization of helium carrier gas for helium detector applications

“…The introduction of the helium ionization detector led to an efficient method to achieve an ultra-high-purity grade of helium (minimum purity of 99.9995%). In such grades of helium, impurities are in the range of a few parts per billion (1,2). Using this grade of helium in a leak-free chromatographic system, the detector will characteristically respond negatively to a small concentration of selected gases (Ne, H2, Ar, 02, and N2) and positively to other gases (3)(4)(5).…”