Adsorption of catechol, resorcinol, hydroquinone, and their derivatives: a review

In recent years, there has been an increasing interest in finding innovative solutions for the efficient removal of contaminants from water, soil, and air. The present study reviews the adsorptive removal of catechol (C), resorcinol (R), hydroquinone (HQ), and their derivatives from various adsorbents. As an effective, efficient, and economic approach for water purification, adsorbents and adsorption processes have been widely studied and applied in different aspects for a long time. The role of various adsorbent materials like activated carbon, activated carbon cloth, carbon nanotubes, polymeric resins, organic clays, Fe(OH)2, and TiO2 was discussed together with that of other experimental parameters. In all the synthetic resins, particularly, aminated hypercrosslinked polymers have good adsorption capability for phenols. These polymeric adsorbents are suitable for industrial effluents containing C, R, HQ, and their derivatives. The adsorption capacities of the adsorbents reviewed here vary significantly depending on the characteristics of the individual adsorbent, the extent of chemical modifications, and the concentrations of solutes.