Using an ion exchange method from Ca-bentonite, Tin (Sn)-bentonite was synthesized and characterized by X-ray fluorescence spectrometry (XRF). The concentration of tin was determined using Microwave Plasma Atomic Emission Spectroscopy (MP-AES) from a tin-chloride (SnCl2) solution. The aim was to identify the minimum amount of Sn-bentonite required for successful pertechnetate ion sorption, considering various conditions such as Sn concentration, pH, redox potential values, and kinetic studies. Sn-bentonite demonstrated high efficiency in removing radioactive pertechnetate anion (99mTcO_4^-) through a redox reaction (Sn(II/IV)- TcO_4^-) in an aqueous medium, and thus has potential as a suitable sorbent for radioactive waste management. These findings could aid in designing radioactive waste repositories and engineering barriers to prevent pollutants from being released into the environment.