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Because of spontaneous agglomeration effect and undesirable electronic state of Zr sites on the surface, zirconium (hydro)oxides generally exhibit suboptimal defluoridation capacity. Herein, a template confinement‐ligand anchoring strategy is developed by utilizing confined growth of zirconium hydroxide (ZH) inside chitosan hydrogel beads (CHB) and subsequent anchoring of fumaric acid (fm) on its surface Zr sites in a monodentate mononuclear coordination mode. This technique leads to uniform dispersion of ultrafine fmZH (≈3.4 nm) and tunable electron density at the Zr sites. Due to the electron‐withdrawing ability of fm, electron‐delocalized Zr sites increase the orbital energy level matching and vacate Zr 4d orbitals to promote hybridization with the F 2p orbitals. Ultimately, robust ZrF bond can be formed as a result of reduced the adsorption energy toward fluoride ions. The defluoridation capacity shows positive linear relationship with the electron extraction ability of ligands. The saturation adsorption capacity and dynamic treatment capacity of CHB@fmZH are 10.8 and 45.9 times higher than that of CHB@ZH, respectively, owing to high electron extraction (0.098 e−) of fm. This study offers a novel insight into the design and synthesis of high‐efficiency metal oxide adsorbents by steering its surface metal sites’ electronic state through ligand effect.

Pyrolysis of paper and polyethylene in Tetra Pak waste occurred at 368 and 490 °C, respectively, while aluminum did not melted until the temperature reached 660 °C, thus aluminum and char can be obtained by carbonization of Tetra Pak waste at 550 °C. Pyrolytic char was processed into porous carbons by different methods. Specific surface area of the porous carbon prepared by carbonization of acid‐washed char at 850 °C achieved 741 m2 g−1, and the specific surface area of the porous carbon prepared from char by successively carbonization at 850 °C and acid‐washing was 732 m2 g−1. The developed porous structure was formed due to the polymerization of char above 650 °C, while the etching of char by CO2 generated via decomposition of inherent calcite led to a lower microporosity. Methylene blue adsorption capacity of the optimized sample reached 140 mg g−1, and the equilibrium data followed Langmuir model.