Abstract: The device for ionophoresis combines a donor electrode assembly, a counter electrode assembly and a generator of electricity. The donor assembly comprises a primary reservoir element containing the active principle and a secondary reservoir element containing a neutral electrolyte, these reservoir elements being separated by a semipermeable membrane in polymer material in contact with each of them, and an electrode in contact with the secondary reservoir element. The polymer material of the membrane consists at least in polyethyerblocamide with an Mn between 10000 and 300000 and containing by weight, 35% to 90% of polyamide sequences. The invention is applicable to the transcutaneous administration of active principles to a subject with improved efficiency.

Abstract: In order to remove the salts (in particular NH.sub.4 Cl) present in an aqueous sulphonamide solution (in particular CH.sub.3 SO.sub.2 NH.sub.2), the solution is subjected to a two-compartment electrodialysis. By maintaining the pH at a value below 7, the formation of ammonia is avoided. The demineralized solution can be concentrated in order to receover after crystallization, the sulphonamide.

Abstract: An electrodialysis method using a bipolar membrane (BP) for regenerating acids, wherein a series of base (B), acid (A) and salt (S) compartments are provided between a positive electrode (anode) and a negative electrode (cathode), said compartments being defined by a series of membranes: cationic, bipolar, anionic, cationic, bipolar and so forth, and a solution being circulated through each compartment. An additional anionic membrane (10) is applied to the anionic side (11) of the bipolar membrane (BP) with no discernible gap therebetween so that contamination of the acid compartment by cations is reduced.

Abstract: Process for the treatment of drilling muds recovered at the surface of the ground, especially synthetic muds, characterized in that it comprises at least one stage of hydrolysis of said mud by means of a lipase.