Patent Number: 041586395
Section: summary

BACKGROUND This application relates to a process for the storing of gas by high temperature and pressure absorption, aadsorption or reaction with a capturing solid bed. In particular, the process relates to storing radioactive krypton (.sup.85 Kr) and other gases absorbed in zeolites. Other applications will become apparent to those skilled in the art. The encapsulation of gases in zeolites is known and it has been taught that the encapsulation of radioactive krypton (.sup.85 Kr) takes place under high temperatures and pressures. (See Brown et al. ".sup.85 Kr Storage by Zeolite Encapsulation," 14th ERDA Air Cleaning Conference). Following the absorption and cooling, the pressure may be lowered without the loaded zeolite releasing the krypton. The process suggested to date for encapsulation has a distinct drawback; namely, it cannot be carried out without contamination of the autoclave reaction vessel; and/or the atmosphere. For example, it has been proposed to place the zeolite in a mesh basket, to lower the basket into an autoclave and to pressurize the autoclave with krypton. After loading the zeolite, the excess krypton is pumped out of the autoclave and the basket is removed through the atmosphere and placed in a sealable container for storage. The possibilities for contamination of the atmosphere are many. Worse yet, the loaded zeolite can be exposed to moisture in the air. As krypton 85 decays, rubidium 85 is produced which can react with the absorped moisture to form a strong caustic and hydrogen. The caustic can cause corrosion of the container and the hydrogen can result in gas pressure buildup in the container. It is an advantage according to this invention to provide a process for the encapsulation of radioactive gas or the like without exposing the atmosphere or even the interior of the autoclave to the dangerous gas. The process has application where it is desired to react gases with capturing solids at elevated temperatures and pressures. SUMMARY OF THE INVENTION Briefly, according to this invention, there is provided a process of storing gas by high temperature and pressure absorption, adsorption or reaction with the bed of capturing solids comprising a first step of placing the capturing solids in a relatively thin-walled container having an opening therein connectable to a conduit. The container need only be able to withstand small pressures across its body of say 25 psi. Preferably the container has a relatively large opening at the top for introducing the capturing solids to the container and a lid sealing the large opening. Built into the lid is a valve which, when opened, provides communication between the interior of the container or canister and a fitting connectable to a conduit. A second step of the process comprises placing the thin-walled container in a pressurizable autoclave. A third step comprises bringing the interior of the thin-walled canister into communication with a conduit extending through the walls of the autoclave and communicating with a source of the gas to be stored. Typically, this comprises a connection between the fitting above described and a fitting in the wall of the autoclave. A fourth step comprises simultaneously pressurizing the autoclave and the interior of the thin-walled vessel by pumping gas to be stored into the thin-walled vessel and inert gas into the autoclave external the thin-walled vessel. The gas to be stored is continuously pumped into the thin-walled vessel as it is being absorbed, adsorbed or reacted with the capturing solids. When the bed of solids can no longer capture additional gas, a fifth step comprises first cooling and thereafter depressurizing the autoclave and the thin-walled vessel. In a final step, the autoclave is opened; the conduit from the thin-walled vessel disconnected; the vessel is sealed and removed to provide a substantially nonpressurized container loaded with absorbed, adsorbed or reacted gases.