Until 1960, technetium was available only in small amounts. The chemistry of technetium is related to that of rhenium. Here is a brief summary of the isolation of technetium. It is never necessary to make a sample of techntium anywhere other than specialist laboratories. This is because technetium is radioactive.
Technetium is a byproduct of the nuclear industry and is a product of uranium decay.
Alternatively it can be made by the bombardment of molydenum targets with deuterium nuclei.