Abstract: Heavy metals are considered as some of the toxic substances that pollute water globally, as such, they tend to have negative effects on living organisms. Manganese and chromium metals exist in different oxidation states which some are dangerous at their low concentrations and they can cause dementia, anxiety, and ataxia, and nervous system problems. The main aim of this study was to produce PCS, hydrochar, and AC from wood chips and evaluate their potential as adsorbents for toxic inorganic ions from aqueous systems. The hydrochar was successfully produced by hydrothermal carbonization (HTC) of eucalyptus wood chips in the presence of a catalyst, water as a solvent, under the temperature of 240 °C and pressure of 4 bars. The activated carbon (AC) was generated by heating the hydrochar in a tube furnace, this process is called annealing. The hydrochar and AC were used as adsorbents for the removal of Mn(II) and Cr(VI) from aqueous solutions. The hydrochar and AC were characterized by sophisticated analytical instruments such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray powder diffraction (XRD), thermogravimetric analyzer (TGA), energy dispersive x-ray (EDX), Dynamic Light Scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET)...M.Sc. (Chemistry