Evaluation of adsorption efficiency of tea residues in the removal of two chalcones prepared from 2-Acetylbenzofuran

The study aims to evaluate the efficiency of using tea residues in removing two chalcone namely 1-(benzofuran-2-yl)-3-(4-chloro phenyl) prop-2-en-1-one (Ch2) and 1-(benzofuran-2-yl)-3-(4-(dimethyl amino) phenyl) prop-2-en-1-one (Ch1), which are derived from 2-acetylbenzofuran from aqueous solutions. The research included studying the influence of some factors on the efficiency and adsorption capacity, including (adsorbent dose, contact time, initial chalcone concentration, pH, and initial temperature). The highest removal percentage was (90.36%) for (Ch1) at initial concentration (20 ppm), and (80.59%) for (Ch2) at initial concentration (50 ppm). The contact time was (30 min.) for each of two chalcones in normal pH and temperature (30°C). The study also included studying the adsorption isotherm by applying four models, which are (Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich), and it was found that the adsorption process follows the Langmuir model. In addition, the adsorption kinetics were studied by applying four kinetic models, and it was found that it follow the pseudo-second-order model. The study also included a thermodynamic study of the adsorption process, which revealed that the adsorption process occurs spontaneously and the reaction is exothermic, in addition to a decrease in randomness where the chalcone molecules are more ordered on the surface of the tea residues than they are in the solution.