Application of Physical Statistical Modeling in the Adsorption of the Drug Ketoprofen and the 2,4-D Herbicide using the Bark Campomanesia Guazumifolia Forest Species Modified with H2SO4 as an Adsorbent

Emerging pollutants are a widespread environmental concern, andadsorption represents one of the choices available for the removal of suchcompounds from polluted waters. However, the set-up of a new adsorption system requiresthe experimental determination of adsorption isotherms and their thoroughmodelling, for the sake of a convenient optimization. In this work, the Campomanesia guazumifolia biomass is adopted as precursor for the synthesis of anew adsorbent and then tested for the adsorption of KTP and 2,4-D. Theadsorption performances of this biomass are significantly improved through atreatment with sulfuric acid, which allows obtaining higher removal efficiency ofthe target organic molecules. The experimental isotherms are measured at 298 – 328 K and pH 2. An ETAM model is employed for amodeling analysis of the experimental data, for the comprehension of theoccurring adsorption mechanism. Results demonstrated that adsorption of KTP isendothermic and occurs in multilayer with a multimolecular process, in whichthe molecular aggregation can be predicted. On the contrary, the adsorption of 2,4-D on this functionalized biomass is exothermic. The adsorption energiesresulted to be < 40 kJ mol−1, indicating that physical adsorption forces are involved inthe removal of these organic molecules.