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Calix[4]pyrrole‐based porous organic polymers (P1–P3) for removing organic micropollutants from water were prepared. A bowl‐shaped α,α,α,α‐tetraalkynyl calix[4]pyrrole and diketopyrrolopyrrole monomer were crosslinked via Sonogashira coupling to produce a 3D network polymer, P1. P1 proved too hydrophobic for use as an adsorbent and was converted to the corresponding neutral polymer P2 (containing carboxylic acid groups) and its anionic derivative P3 (containing carboxylate anion groups). Anionic P3 outperformed P2 in screening studies involving a variety of model organic micropollutants of different charge, hydrophilicity and functionality. P3 proved particularly effective for cationic micropollutants. The theoretical maximum adsorption capacity (qmax,e) of P3 reached 454 mg g−1 for the dye methylene blue, 344 mg g−1 for the pesticide paraquat, and 495 mg g−1 for diquat. These uptake values are significantly higher than those of most synthetic adsorbent materials reported to date. [ABSTRACT FROM AUTHOR]

Biochar is regarded as a promising new class of materials due to its multifunctional character and the possibility of effectively coupling different properties. With increasing introduction into the environment, environmental chemicals such as surfactants will load onto the released biochar and change its physicochemical characteristics and adsorption behavior toward pollutants. In this study, sodium dodecyl sulfate (SDS), as one type of anionic surfactant, was coated onto biochar with different loading amounts. The influence of SDS loading onto biochar's physicochemical properties were investigated by Fourier transform infrared (FT-IR) spectroscopy, elemental analysis, zeta potential and Brunauer–Emmett–Teller (BET) surface area and pore size distribution analysis. Results showed that the pore size of the biochar decreased gradually with the increase of SDS loading because of the surface-adsorption and pore-blocking processes; the pH of the point of zero charge (pH PZC ) decreased with increasing SDS loading. Although surface-coating with SDS decreased the pore size of the biochar, its adsorption capacity toward Methylene Blue (MB) significantly increased. The biochar-bound SDS introduced functional groups and negative charges to the biochar surface, which could thus enhance the adsorption of MB via hydrogen bonding and electrostatic interaction. The results can shed light on the underlying mechanism of the influence of anionic surfactants on the adsorption of MB by biochar. [ABSTRACT FROM AUTHOR]