Abstract: A plate-shaped heat exchanger (20, 120) for a heat exchange unit (40) of a chemical reactor (60), that advantageously presents a thermal insulation obtained in an unusually simple and reliable manner, has a substantially flattened box-like structure (22), with a substantially parallelepiped, rectangular configuration, defining an internal chamber (24), and comprises an inlet connection (28) and an outlet connection (29) of a heat exchange operating fluid into and from said chamber (24), and a distributor pipe (10, 110) of said operating fluid inside said chamber (24), extended in said structure (22) at a long side (22a) of it, said distributor pipe (10, 110) comprising a first tube (30, 130) and a second tube (32, 132), positioned one inside the other, between said tubes, respectively external tube (30) and internal tube (32, 132), an interspace (30a) being defined in fluid communication, on one side, with said chamber (24) through a plurality of openings (26) provided in the external tube (30, 130) of said d

Abstract: A method for controlling the pseudo-isothermicity of a chemical reaction in a respective reaction zone. (9) in which the use of heat exchangers (6) is foreseen having an operating heat exchange fluid flowing through them and in which heat exchange critical areas (9a) are identified, the method being distinguished by the fact that it reduces and controls, in the critical areas (9a) of the reaction zone, the value of the heat exchange coefficient between the operating fluid and the zone (9), through thermal insulation of the portions (6a, 6b) of such exchangers extending in such areas (9a).