This study focuses on the development of an adsorbent derived from oil sludge activated with sulfuric acid (H2SO4) using a hydrothermal method as a solution for reducing hazardous and toxic waste (B3). The high carbon, iron, and aluminium content in the sludge was utilized to synthesize Al-Fe/C oxide adsorbents for the removal of methylene blue and eriochrome black T dyes. The research aimed to…