Study On The Adsorption For Xenon On Adsorbents

During its normal operation, nuclear power plants will produce some radioactive noble gases (Krypton and Xenon). To minimize the release amount of radioactive gases to the environment, they need to be disposed before releasing to the atmosphere.At the same time radioactive noble gas monitoring is an important part of the Comprehensive Nuclear-Test-Ban Treaty radionuclide verification.However, the total concentration of xenon isotopes is only0.087×10-6(V/V)in atmosphere. The concentration of radio xenon (mainly131m Xe,135Xe,133Xe and133mXe) are much less, so it is difficult to separate and purify xenon from air. The key technology is the adsorption of xenon.Therefore it is important to study the adsorption properties of xenon, to seek better absorption xenon adsorbent and examine the various factors and conditions affecting the adsorption.This topic studied the adsorption properties of xenon in the traditional adsorbents and the traditional xenon adsorbent (activated carbon) was modified to improve its adsorption properties, and the effects of the modified conditions on the adsorption properties. Also explore the adsorption effect of xenon on the other adsorbent and to draw optimal experimental conditions to study it. Plain the xenon adsorption mechanism on the adsorbent. The results are described below:1.The order of the Xenon adsorption capacity is as follows:AC/KOH-1>AC/KOH-2>AC. We also can see that the adsorption amount of AC/KOH-1and AC/KOH-2just about right but specific surface area of AC/KOH-1is a lot more than AC/KOH-1’S. That is because that with the specific surface area of AC/KOH-1increased but the number of its micropores not increased as the same amplitude. It explained that specific surface area is not decisive factors, and activator made AC/KOH-1’s specific surface area increased. On the one hand the AC had new micropores formed, on the other hand its original microporous were destroyed or changed, the total number of microporous did not increased. So the number of micropores determines the Xenon adsorption 2.Many investigations have shown that although zeolite10X has not large specific surface area, it has many microporous and distributed evenly and its density is relatively higher than AC’s, so unit volume of the adsorption capacity of it is relatively larger. So it can be used as xenon absorbent for xenon sampler which will be furnished in stations of international radio-nuclides monitoring system.3.The factors of temperature, reaction density,H2O,CO2and flow rate that influence dynamic adsorption capability of xenon on zeolite10X were researched.The experiment drew the optimal experimental conditions of Xenon adsorption on zeolite10X.4.After regeneration of zeolite10X molecular sieve adsorption properties with the first use of xenon slightly lower than that after the first regeneration and the same time showed that after repeated regeneration of10X molecular sieve adsorption capacity is almost no difference between the xenon.At a temperature of170℃or above,the desorption efficiency of xenon over97%.Therefore, in practical application, select the10X molecular sieve adsorbent as xenon can be adsorbed xenon and parse out the purpose of detecting, also laid a good foundation for the10X zeolite reuse.5.The specific surface area is not the decisive factors.The number of micropores determines the Xenon adsorption.When the pore size were0.6-0.9nm it is most favorable to the Xenon adsorption capacity.