The present disclosure relates processes and systems for producing and/or purifying 68Ga from an irradiated substrate of 68Zn. In some embodiments, the process rely on the use two cation-exchange chromatography columns to separate 68Ga from 68Zn and other radionuclides and metallic impurities. The process achieves a high overall yield of 68Ga and a high effective molar activity while being implementable in a time compatible with the short half-life of 68Ga. In additional embodiments, the process is implemented by an automated system.