This document discusses technetium separation technologies from spent nuclear fuel. It begins with an overview of technetium discovery and properties. The main challenges of technetium include its interference in uranium/plutonium separation in reprocessing and its accumulation in high-level nuclear waste streams. The document then reviews various separation approaches developed in different countries, including precipitation, gas adsorption, ion exchange, liquid-liquid extraction. It highlights Russian experience with improved PUREX processes and development of ion exchange separation of technetium. The document emphasizes that fundamental studies of technetium chemistry have helped develop better separation methods and manage the challenges of technetium in nuclear applications.