Surfactant-Modified Construction Waste Bricks for the Removal of Diclofenac from Aqueous Solutions

Abstract

This study aimed to enhance the efficiency of construction waste bricks (PRBPs) in removing diclofenac (DFC) by preparing surfactant-modified waste bricks (CCBPs) as adsorbents. The properties of the adsorbents were analyzed, and the parameters related to the adsorption process were examined. The findings demonstrate that the addition of cetyltrimethyl ammonium bromide (CTAB) significantly improved the ability of the waste bricks to adsorb DCF. The pH values affected the adsorption behavior, with the adsorption decreasing as the pH increased. The adsorption process followed the pseudo-first-order kinetic equation, and the rate of adsorption was fast. The Langmuir model was used to fit the adsorption isotherms. According to the adsorption thermodynamics, the adsorption of DCF onto both adsorbents was exothermic, and it was more favorable at lower temperatures. The adsorption capacity of the CCBPs decreased sharply as the KCl concentration increased. The mechanism of adsorption might be explained by the interplay of the π-π interaction, surface complexation, and electrostatic interaction. This study offers a new method for removing micropollutants from aqueous solutions using waste bricks, thus extending the scope of their reuse applications.