Hydrate-based decontamination of toxic gases

Areas in which toxic material has been released, particularly in gaseous form but also in liquid form, are decontaminated by forming gas hydrate of the toxic agent. Smaller-molecule toxic agents form sI or sII type hydrates, whereas larger-molecule toxic agents for sH type hydrates. A "companion gas" or "companion agent" is supplied to fill the smaller voids of the sH hydrate, thereby enabling larger-molecule toxic agents to form hydrates by filling the larger voids of the sH hydrate which, but for the presence of the smaller-molecule agent in the smaller voids, would be unstable and not form. Portable as well as fixed, permanently installed apparatus for conducting hydrate-based decontamination is also disclosed.