Plugged hexagonal templated SiO2 was modified with HS(CH2)(3)Si(OMe)(3) and H2O2 and then used in a proportion of 0.1 g/10 mL in 2-propanol soln. for boldine adsorption (concns. 0.1-5 g/L). Adsorption isotherms were detd. by using Freundlich, Langmuir, Dubinin-Radushkevich, Dubinin-Astakhov and Redlibh-Peterson models. The isotherm parameters were estd. by linear regression and nonlinear fitting analysis. The equil. adsorption data were best described by the Redlich -Peterson isotherm model. Adsorption efficiency (over 90%) was achieved only for initial adsorbate concns. below 380 mg/L.