In this research, a suitable method was designed and developed to optimize thallium adsorption capacity under various aqueous conditions. A Prussian Blue inorganic complex was selected as the adsorbent for extraction without the use of a surface-modifying agent. Thallium was adsorbed onto a small amount of Prussian Blue (PB), and the concentration of the eluted solution was measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The effects of pH, adsorbent dosage, and crystal lattice moisture (thermodynamic variables), as well as agitation time and rate (kinetic variables), were investigated and optimized. The optimal conditions revealed how the binding capacity of Prussian Blue for thallium evolves over time at different concentrations. Based on 24-hour binding data, Langmuir isotherm analysis was used to assess chemical adsorption, yielding a maximum binding capacity of 420 mg g⁻¹. The proposed system aims to separate and extract thallium from aqueous waste streams.