Getter Material

Gettering. Gettering materials, such as zirconium or titanium alloys, are heated to 400°C. At that temperature, they react with the impurities in the gas stream such as O2, H2O, N2, H2, CO, CO2, and hydrocarbons. Total impurities can be reduced to <100 ppb. 

Fig. 5.1. Commercial storage vessel for liquid 4He (A connection for transfer tube, B overflow valve, C safety valve, D manometer, E vacuum and safety valves, F gas valve, G getter material, H adsorbent material,...

In attempting to assess the disposition of sulfur in the overall synfuels system, one must first examine the characteristics of the sulfur in the feedstock. Then, the feedstock is examined for sulfur "getter" materials. With evaluation of the operating parameters of the primary energy conversion reaction system, the fate of sulfur in the feedstock can be projected. 

Olher mudern getter materials include cesium-rubidium alloys, tantalum. titanium, zirconium, and several of the rare-earth elements, such as hafnium,... 

Figure 3. Adsorption isotherms of ST707 getter material.

Metallic barium is little used industrially, its worldwide production being estimated to be a few tons (30 to 40 t). It is utilized in the manufacture of vacuum tubes (television tubes) and as a getter-material for removing undesirable trace gases. 

Chemisorbents as effective getter materials for toxic process gas and liquid streams. 

Fig. 2.5 is a diagram of the Ar gas purification and delivery line. An essential part of the delivery line was a RD Mathis GP-lOO noble gas purifier incorporating Ti getter material °2,106 quartz tube. Starting from a high purity gas... 

A multilayer insulation consisting of a reflective foil fixed on the outside of the inner vessel is usually chosen to minimize the transport of radiation heat With increasing number of radiation shields, however, additional heat transfer is introduced due to conduction via physical contact An optimal number is between about 60 and 100 layers [51]. The whole remainder of the intermediate space, in larger vessels about 1 m in thickness, serves as a vacuum jacket to avoid heat transport by convection or residual gas conduction. A typical pressure value in this space is < 0.013 Pa. Appropriate getter materials help maintain the vacuum over longer times. 

These examples show that for medium and long term applications (> 2-3 years) a simple desiccant is not enough and specific getter materials have to be added to sorb the extra amount of gases generated in the panel. 

Table 19.23. Selected properties of getters and scavengers Typical getter material Type...

Presputtering of some effective gettering material such as Titanium or Silicon before the analysis of the material of interest... 

The problem could be solved by addition of Al203-rich clay as getter material for volatile alkah compounds mixed during coal briquetting. Continuous operation could be extended to 523 hours and the steam-oxygen ratio was lowered to 10kg/m (STP) for sodium oxide contents of 16-21 wt% in the ash and addition of 6 kg clay to 100 kg raw coal [189,196]. 

The requirement of a helium-leak test for a MEMS device package with an internal volume of around 0.001 cc or below for chronic implantation (>10 years) is definitely beyond the capability of any current helium-leak detector. That is where getter materials come into play. A getter material can absorb various gaseous species and can be used to extend the effective lifetime of a medical device by absorbing moisture and other detrimental gas species, such as hydrogen [104—106] and oxygen [40]. 

Bredendiek-Kamper S, Klewe-Nebenius H, Pfennig G et al. (1989) Surface analytical characterization of the hydrogen getter material ZrCo. Fresenius Journal of Analytical Chemistry 335 669-674... 

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