This study explores biochar (BC) derived from date palm seeds as a high-performance adsorbent for the removal of trichloroethylene (TCE) and tetrachloroethylene (PCE) from aqueous solutions, with comparative analysis against commercial activated carbon (AC). The optimized BC, characterized by a high BET surface area of 654.79 m2/g and unique nanotube morphology, demonstrated superior adsorption capacities of 86.68 mg/g for TCE and 85.97 mg/g for PCE, significantly surpassing the AC under identical conditions. Kinetic studies identified the pseudo-second-order model as the best fit, indicating chemisorption as the dominant mechanism. Isotherm modeling revealed a combination of multilayer and monolayer adsorption processes, underscoring the complexity of the BC’s adsorption behavior. Statistical analysis via two-way ANOVA further validated the BC’s significant superiority over the AC (p < 0.0001) for both contaminants. These results highlight the potential of date-palm-seed-derived biochar as a sustainable and cost-effective adsorbent for eco-friendly water treatment, emphasizing its role in reducing environmental impact and operational costs in real-world applications.