Ultra high purity hydrogen

The constricted part of the tube (Fig. la) was then sealed off, sample transferred in vacua into the Infrasil cell and reduced by hydrogen (Ultra-high purity, Air Products) at 1 atm and 200°C for 14 h in an apparatus (Fig. lb). The temperature of 200°C gives rise to almost complete reduction of the Cu Y to Cu Y without reducing further to Cu° (4). ... 

Traditionally PSA processes have found particularly widespread application in hydrogen production systems wherein the PSA unit is used to produce ultra-high purity hydrogen (99.999%+) from steam-reformed hydrocarbons and other hydrogen sources. However, several limitations have existed with these processes. 

Argon (Ultra High Purity, 99.999%), hydrogen (Research Purity, 99.9995%) and ethylene (Research Purity, 99.99%) were purchased from Matheson. The argon was further purified using a Matheson Gas Purifier Model 6406in conjunction with an Alltech indicating oxy-trap. 

Of course, use of Pressure Swing Adsorption for C02 removal would produce equivalent ultra-high purity hydrogen from either SGP or SMR-based plants. 

Hydrogen can be produced by steam methane reformation (the most widely used process) or by off-gas purification. Hydrogen can be produced at normal purity (95-98%) or at ultra-high purity (99.99%). The first step to obtain pure hydrogen in the steam reformer process when using a natural gas feedstock is to perform a pretreatment. There are small amounts of sulfur in natural gas that must be... 

Hydrogen can be purchased in various grades of purity. Research grade is 99.9995%, ultra high purity is 99.999%, high purity is 99.99%, and industrial grade is 99.95%. Of course, the purer the gas, the more expensive it is. 

The input feed stream is composed of an effluent gas (argon) and one of the hydrogen isotopes, H or D, at a time. The output species from reactor were monitored by the mass spectrometer, with a constant inner pressure of 6 x 10 torr. The gases used in all experiments are of ultra high purity (min 99.99 % voL). 

Ceramic Membrane Devices for Ultra-High Purity Hydrogen Production Mixed Conducting Membrane Development... 

Miyazaki, T. Kajiyama, K. Matsumoto, H. Fujiwara, M. Yatabe, Ultra high purity hydrogen gas supply system with liquid hydrogen, Int.J. Hydrogen Energy 1996, 21(5), 335-341. 

As with hydrogen, determine your air requirements from Tables 10.1 and 10.2 and yonr instrument manuals. One unit can provide ultra-high-purity air to multiple detectors. Be sure to plan for extra capacity, even if it means buying an extra unit—do not run generators at 100% of capacity. 

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