GB738816A - Improvements relating to gas generators - Google Patents

Abstract

<PICT:0738816/IV (b)/1> A gas generator for the production of a gas by the reaction of a liquid and a solid comprises two separate closed vessels in which the solid and liquid respectively can be maintained under gas pressure, the said vessels being in communication through a porous element so that the passage of liquid into the vessel containing the solid is dependent on the relative gas pressures in the two vessels, the gas space in the vessel containing the liquid being connected to the outside atmosphere through a controlled leak comprising a second porous element. The second porous element may comprise a U-tube, partly filled with liquid to cover the porous element and communicates with the said gas space at one end and with the outside atmosphere at the other end. The generator is particularly suitable for the preparation of hydrogen sulphide or hydrogen. In the Figure, the vessel 2 of generally tubular shape and preferably with an enlarged middle portion 2a contains the solid reactant 5 resting on a porous plate 6. The liquid reactant is contained in vessel 1 and a second porous plate communicates between the gas space in this vessel and the outside atmosphere, e.g. by the U-tube 12 containing the porous plate 11 which may be covered with water, glycerine or other suitable liquid. On opening control valve 8, the liquid reactant passes through the porous plate 6 to the solid reactant and the generated gas passes out through valve 8. When the valve 8 is closed gas pressure forces liquid back into vessel 1 thus creating a pressure above the liquid 4. The controlled leak prevents an excessive pressure developing in the vessel 1. The pressures developed in the vessels 1 and 2 can be controlled by the porosities of the two porous elements 6 and 11 which may be sintered glass discs, or may be made of porcelain or of foamed polyvinyl chloride, rubber, polystyrene or methyl methacrylate, or of plastic-bonded inorganic materials such as kieselguhr.