Abstract: A reaction chamber (E) comprises a calender reactor (5) comprising a device (4) for introducing a feedstock; a device (6) for carrying off the treated feedstock; at least two elementary reaction cells (52), not contiguous to one another, each one consisting of an individual feedstock distributor, an individual collector of the treated feedstock, and a catalytic bed, the cells being separated from one another by a channel (51); at least one device (V) for circulating a heat-carrying fluid in each channel (51); at least n partitions (S) for separating the flow of the heat-carrying fluid, n being an integer greater than or equal to 1; and at least n+1 means (T) for heating the heat-carrying fluid. The chamber can be used for performing the catalytic reforming of naphtha under low pressure.

Abstract: A mixture of at least two constituents A and B is submitted to selective separation across a selective membrane.The membrane comprises an active layer comprising particles of a selective solid (5) dispersed in a continuous non-porous and non-elastomeric polymer phase (4) and a porous support (6). The thickness of the active layer is less than 100 micrometers, advantageously less than 20 micrometers.

Abstract: A heat exchange device is provided whose exchange zone is formed by juxtaposing a plurality of plates parallel with each other and spaced apart two-by-two by a plurality of spacing elements consisting of spacers parallel to each other, which may be crenellated (they then comprise crenels and projecting parts) or continuous, said plates being formed so that for any two adjacent plates, at least one of the facing faces is provided with spacers, at least one part of said spacers being, over at least a part of their length, in contact with the facing face of the adjacent plate or with at least a part of the spacers possibly present on said facing face, over at least a part of their length, said plates, defining flow spacers for two fluids being further formed and disposed so that for one flow space out of two the spacers carried by at least one of the facing faces of two adjacent plates defining said space are crenellated spacers. The fluids flow advantageously in cross-current relation.

Abstract: The invention relates to a process for the simultaneous exchange of heat and matter through a porous wall. A relatively hot gaseous mixture of two constituents passes through an exchange compartment by flowing along the first surface of a porous wall and is progressively cooled, which causes the condensation of a fraction of said mixture. This fraction is vaporized on the second surface of the wall in contact with a relatively cold gas. This process is useful for the fractionation of a mixture of two constituents of a gas, for example, of a mixture of pentane and heptane.

Abstract: A method of transferring heat from a hot fluid to a cold fluid by means of a heat carrying fluid formed from at least two non azeotropic constituents contained in a looped circuit. The hot fluid gives up its heat in an exchanger, this heat being used for evaporating the heat carrying fluid which is then condensed in an exchanger while giving up its condensation heat to the cold fluid. A heat carrying agent reservoir accomodates the heat flux variations and a system imposes a flow direction on the heat carrying fluid.

Abstract: A heat exchange device is provided whose exchange zone is formed by juxtaposing a plurality of plates parallel with each other and spaced apart two by two by a plurality of spacing elements consisting of spacers parallel to each other, which may be crenellated (they then comprise crenels and projecting parts) or continuous, said plates being formed so that for any two adjacent plates, at lest one of the facing faces is provided with spacers, at least one part of said spacers being, over at least a part of their length, in contct with the facing face of the adjacent plate or with at least a part of the spacers possibly present on said facing face, over at least a part of their length, said plates, defining flow spaces for two fluids being further formed and disposed so that for one flow space out of two the spacers carried by at least one of the facing faces of two adjacent plates defining said space are crenellated spacers. The fluids flow advantageous in cross-current relation.

Abstract: A heat exchange device is provided whose exchange zone is formed of a stack of perforated plates having perforations disposed so that superimposition of the perforations creates flow spaces for at least two fluids at different temperatures, said perforated plates being separated two by two by at least one seal disposed so that each perforation of the plates corresponding to a flow space through which fluid passes is separated from the perforations corresponding to the flow spaces through which a different fluid passes, said stack being kept at a clamping pressure of 2 to 50 bars by means of a plurality of tie-rods passing through it and said seal being formed by an expanded graphite manufactured under such conditions that it has a bulk density of about 200 to 500 kg.m.sup.-3.

Abstract: A heat exchange device comprises at least one zone for the circulation of at least two fluids in heat exchange relationship and input and output means for these fluids, the zone being of modular structure and consisting essentially of a stacking of lattices jointly assembled and each formed of two series of intercrossed walls. The stacking of lattices define spaces for the circulation of the fluids, each lattice, which constitutes a module, being formed in one piece and so designed that, on each face thereof, the edges of the walls of one of the two series are protruding from the plane formed by the edges of the walls of the other series. The lattice stacking is achieved by registering the protruding edges of a series of walls of one face of any lattice with the recessed edges of the corresponding wall series on the opposite face of the adjacent lattice. The protrusion height is equal to the depth of the registering recess in the lattice stacking.

Abstract: A heat exchanger of modular structure comprises stacked lattices which can engage with each other, and each is formed of two series of intercrossed small plates jointly assembled by mutual engagement at the level of cuts located on the edges of the plates, with spaces being generated for circulating fluids therethrough in heat exchange relationship.

Abstract: The fluid reactant is circulated through a close loop in which is introduced additional fresh fluid under a substantially constant pressure. A fraction of the fluid flow is discharged from the loop during a first period at a substantially constant flow rate, this fluid discharge being discontinued during a second period, said periods repeatedly following one another.

Abstract: In the compartments of the fuel cell are located intermediate elements leaving two free spaces of minimum volume in the vicinity of the two electrodes respectively, which delimit each compartment. These two free spaces extend substantially over the whole area of the electrodes and the intermediate elements are provided with perforations for ionic conduction between the two free spaces.

Abstract: In this fuel cell formed of a stack of electrodes, each electrode is provided, on one of its faces, with protrusions or ribs of limited height which contact the opposite face of an adjacent electrode of the stack.