Compressed Krypton

Values extracted and in some cases rounded off from those cited in Rabinovich (ed.), Theimophysical Propeities of Neon, Ai gon, Krypton and Xenon, Standards Press, Moscow, 1976. m = melting point c = critical point. The notation 6.654.-4 signifies 6.654 X 10 . This source contains values for the compressed state up to 1000 bar, etc. This book was published in English translation by Hemisphere, New York 1988 (604 pp.). 

The definition of w makes its value zero for argon, krypton, and xenon, and experimental data yield compressibility factors for all three fluids that are correlated by the same curves when Z is represented as a function of Tr and Pr. Thus the basic premise of the three-parameter theorem of corresponding states is that all fluids having the same value of w have the same value of Z when compared at the same Tr and Pr. 

Figure 9.8. Possible structures for argon, krypton and xenon adsorbed in registry with graphite. Dotted unit cell Xe linearly expanded by (4.91 -4.40)/4.40 = 11.6%. Dashed unit cell Xe linearly compressed by (4.40-4.26)/4.26 = 3.2%. Kr expanded by (4.26 - 4.07)/4.07 = 4.7% and Ar expanded by (4.26- 3,85)/3.85 = 10.6% (reproduced courtesy of Larher, 1974).

The mobility in krypton is quite high at all pressures and there is only a shallow minimum in this case. The data shown in Fig. 4 are for 20°C, which is well above the critical temperature. The minimum becomes lower at lower temperatures but not as low as in xenon. The electron mobility in krypton is also reasonably well represented by Eq. (4) when the adiabatic compressibility is used. ... 

Los Alamos Laboratory in New Mexico has terminated its work with the ANT ARES system operating at 10.6 micrometers because it was shown it would not be possible to generate sufficient heating or compression with the 10.6 micrometer wave length radiation. They have turned their efforts to the development of krypton-fluorine lasers. They have generated 10,000 joules pulses at 250 nanometers at efficiency of 1.5%. In 1989, this laser system had not yet been incorporated into a fusion test apparatus and little recent data is available. 

The preferred method of disposal of radioactive krypton isotopes, after being separated from other volatile fission products, is by dumping at sea as the compressed gas, confined in steel cylinders. According to a report by Bryant and Jones the cumulative quantities of Kr and in the environment by the year 2000 are such that these nuclides will pose no significant health problem. 

Krypton, Kr, is an elemental, colorless, odorless, inert gas. It is noncombustible, nontoxic, and nonreactive however, it is an asphyxiant gas and will displace oxygen in the air. Krypton 85 is radioactive and has a half-life of 10.3 years. The four-digit UN identification number for krypton is 1056 as a compressed gas and 1970 as a cryogenic liquid. These forms of krypton are not radioactive. Radioactive isotopes of krypton are shipped under radioactive labels and placards as required. Its primary uses are in the activation of phosphors for self-luminous markers, detecting leaks, and in medicine to trace blood flow. 

Cylinders of compressed gases are often labeled to show how many SCF or standard cubic feet of gas they contain. 1 SCF of gas occupies a volume of 1 ft at a standard temperature and pressure of 0°C and 1 atm. A particular cylinder weighs 122 lbs when empty, and 155 lbs when filled with krypton gas at 26°C. How many SCF of Kr does this cylinder contain ... 

The liquid part of oxygen fraction (lA) contaiiung Kr, Xe and oxygen accumulate at the bottom of the left column. The oxygen is evaporated by the heat of compressed air while krypton and xenon in the liquid state. The two can be separated by fractional distillation or by selective adsorption on charcoal. 

DOT Label NON-FLAMMABLE GAS TC Shipping Name Krypton, compressed... 

Gaseous neon, krypton, and xenon must be handled with all the precautions necessary for safety with any nonflammable, nontoxic compressed gas. 

When disposal becomes necessary, vent neon, krypton, and xenon gas slowly to a well-ventilated outdoor location remote from personnel work areas and building air intakes. Do not dispose of any residual neon, krypton, and xenon in compressed gas cylinders. Return cylinders to the supplier with residual pressure, the cylinder valve tightly closed, and the valve caps in place. 

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