Naturally abundant bentonite clay minerals have high cation exchange capacity (80–120 meq/g), greater surface area, enhanced swelling properties with micro and meso-porosity. However, their hydrophilic surface limits their adsorption ability. In the present study, bentonite clay (BT) was modified with a cationic surfactant by using cation exchange reaction to modify its surface from hydrophilic to hydrophobic; thus making it a better adsorbent for the removal of pollutants from contaminated water. The modified clay was characterized through fourier transform infrared spectroscopy, and thermo gravimetric analysis. It was used as an adsorbent for the removal of methyl orange and deltamethrin from aqueous solutions. The results showed that modified bentonite has strong tendency to remove organic pollutants from water. About 97% removal of methyl orange was observed with surfactant modified bentonite in contrast to only 56% removal with unmodified bentonite. Similarly, modified bentonite removed up to 98% deltamethrin as compared to only 47% removal with unmodified bentonite. Kinetic study of both experiments showed that the absorption process follows a pseudo second order equation.

Sana Ahmad and Khizra Yasin