MoO42- ions were sorbed in calcined hydrotalcite contained in a column. It was found that 98% of Tc-99m formed by Mo-99 decay was eluted through the column in the form of pertechnetate. The content of radionuclides was determined by gamma-spectrometry, and natural molybdenum was measured by neutron activation analysis. Solids were characterized by thermal analysis, X-ray diffraction, and infrared spectroscopy. Through batch experiments, the hydrotalcite capacity toward molybdate ions (1.12 x 10(-3) M) was found to be 3.2 mequiv g(-1). It was found that the high molybdate adsorbing capacity of calcined hydrotalcite could be utilized in designing a Tc-99m generator made with low specific activity Mo-99-molybdate samples.