Biomimetic Preparation of Hybrid Porous Adsorbents for Efficiently Purifying Complex Wastewater

Simulating the polymerization of polyphenol on a solid surface in nature, hybrid adsorbents were prepared by coating the hierarchically porous silica (HPS) with a poly(pyrogallol) (PG) layer. Such material has a macroporous skeleton and well-defined mesopores. During a facile and mild reaction, the poly-PG membrane is strongly binded to the pore surface of HPS through covalent and noncovalent interactions. High-performance adsorbents, HPS/PG, was obtained. It exhibits a large capability to adsorb various pollutants in wastewater, such as heavy metal ions (Hg2+, Pb2+, Cu2+, Ni2+, and CrO42–), organic dyes, and pesticides. Specifically, HPS/PG showed a good purifying capacity toward the Hg2+ ion and neutral red, which could reach 157.2 and 671.1 mg g–1, respectively. More than that, HPS/PG showed a good recovering ability with simulated wastewater with complex components. The removal rate for any of the pollutants was more than 98%. The high adsorption capability of HPS/PG should be due to the hierarchicall...