Kinetics and equilibrium of cesium sorption and desorption by particulate nuclear graphite

✍ Scribed by L.R. Zumwalt; N.I. Kazi

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 721 KB
• Volume: 19
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(81)90028-2

✦ Synopsis

Data and a consistent physical and mathematical model for the kinetic and equilibrium sorptive behavior of cesium with a particulate, nuclear-grade graphite (H-451) is given. The most important conclusions are:

(1) The kinetics of absorption and desorption of cesium by H-451 graphite in particulate form (size range 44-74 Frn) is such that, in general, several days are required to reach a near equilibrium state. Accordingly, the radiometric isopiestic method, although time consuming, appears to be the best method for obtaining equilibrium data in the cesium vapor pressure range of about 10 down to 10m4Pa. (2) The kinetics data of the isopiestic experiment with graphite powder was found to be very well represented mathematically by an equation which is based on the site activation energy being approximately equal to the sorbate-sorbent site interaction energy, x. In accordance with a theory for modified-exponential sorption which fits the equilibrium data well, the sites are taken to be non-uniformlv distributed having a number which decreases exponentially with an interaction energy, x, that has a finite upper limit xL.