Pesticides have great potential to contaminate resources of drinking water by percolating and leaching, when applied in the agriculture sector as well as in domestic region. Activated carbon (AC) and Biochar (BCH) were used for adsorption in a fixed-bed column system. Both of the adsorbent-packed columns indicated an increase in the breakthrough time for atrazine from 3350 to 5800 min and 3200 to 5700 min, chlorothalanil 3200–5600 min and 3150–5550 min, β-endosulfan 3050–5400 min and 2950–5400 min, and α-endosulfan 2900–5200 min and 2850–5200 min with bed heights from 10 cm to 15 cm, respectively. Similarly, when flow rate increased from 0.5 to 1.5 mL min−1 and contaminant concentration from 50–100 µg L−1, it resulted in a decrease in exhaust time. The models of Yoon–Nelson (R2 = 0.9427) and Thomas (R2 = 0.9921) describe the process of adsorption to be best well-under optimal conditions. Both the adsorbents would be efficiently utilized as the best adsorbents to remediate pesticide-contaminated water under optimal conditions. Pesticides adsorption onto adsorbents followed the order of atrazine > chlorothalanil > β-endosulfan > α-endosulfan.
