Abstract: The present invention relates to a process for the production of no-carrier added 99Mo by neutron activation of 98Mo thereby reaching specific radioactivity which allow the use of such produced 99Mo as an option for the 99Mo produced by the fission of 235U. This has been achieved by taking advantage of the recoil of the 99Mo nuclei upon the capture of neutrons by the 98Mo containing compound. These recoiled nuclei are no longer chemically bound to the 98Mo containing compound allowing further specific separation. Preferred 98Mo containing compounds are molybdenum(O)hexacarbonyl [(Mo(CO)6] and molybdenum (VI) di oxodioxinate [C4H3(O) —NC5H3) J2-MoO2.