NOVELTY - A magnetic containment device comprises a magnetic field applied to a length of circuit, an iron-magnetic catalyst contained in the length of circuit and a solution of borohydride of alkaline metal and alkaline hydroxide flowing in the circuit. The catalyst material is placed in powder form of variable granulometry, wires, fibers, foils or bars. The grains of powder are made of a metallic protective plating on the iron-magnetic support material.    USE - For generating hydrogen (claimed) useful in fuel cell to produce electrical energy.    ADVANTAGE - The catalyst can be easily inserted, kept or removed from the magnet containment device (reactor), simply by moving the magnetic field. The device permits to get variable hydrogen quantities, increasing or decreasing the contact surface between the catalyst and the reagents. The catalysts provide high reaction kinetics, getting considerable stability in time. The loading, movement and retrieval of the catalytic material are completely safe operations carried out by the user. High performance on the hydrogen generation, since the catalytic material, spontaneously placed along the power lines of the magnetic field, shows its greatest surface for the hydrolysis reaction. A filter container is not necessary to keep the catalytic material in powder, therefore the local pressure drops are minimized. The produced powder remains well contained into the magnetic field without any leakage and thus always capable of supporting the catalytic reaction. It is possible to vary in time the intensity and the direction of the magnetic field applied, giving the permanent magnets a continuous or discontinuous movement, alternating and/or swinging on their position by means of mechanical and/or electromechanical systems. The magnetic containment devices adopted on circuits of process for hydrogen generation on medium and large scale, the solution of using electromagnetic coil components can be considered economically valid.    DESCRIPTION OF DRAWING(S) - The figure shows a magnetic containment device.