[en] The experience in the use of massive targets at isotope separation on-line (ISOL) facilities designed for production of short-lived spallation products being studied, some methods are proposed for high-temperature separation of some radionuclides from targets of that type; the radionuclides in question are of importance for investigations in applied sciences, first of all in nuclear medicine. Two massive targets of mercury and gallium are also considered; they can be employed for separation of spallation products by methods of classical watter chemistry