With the plastic pollution becoming worse, the upcycling of plastic waste into functional materials is a great challenge. Herein, a mechanochemical extrusion approach was developed for processing poly(ethylene terephthalate) (PET) waste into porous carbon materials. The essence of the cyclic extrusion approach lies in the solvent‐free mixing of thermoplastic PET with pore‐directing additive (e. g., silica or zinc chloride) at the molecular level. PET waste could be upcycled into functional carbon with high surface area (up to 1001 m2 g−1), specific shapes, and preferred mechanical strength, after cyclic extrusion and carbonization. Moreover, metal species could be well dispersed onto porous carbons through solvent‐free extrusion, different from traditional loading methods (impregnation method, deposition‐precipitation method). In this manner, mechanochemical extrusion provides an alternative for upcycling plastic waste into value‐added materials.

The mesoporous carbon‐supported metal catalysts are important materials in heterogeneous catalysis. From the standpoint of process intensification, the current synthesis methods still suffer from several issues, such as the excessive use of toxic solvents, the time‐consuming self‐assembly process, and the difficulty of continuous production. Herein, we report a solvent‐free and continuous route to synthesize mesoporous carbon‐supported metal catalysts. Interestingly, the use of cyclic extrusion could promote mixing, coordination, and assembly of catalyst precursors (tannin‐metal salts‐additives) by shearing and squeeze force. The as‐made mesoporous carbon‐supported nickel materials showed high surface areas (up to 512 m2 g−1), narrow pore size distribution (~10 nm), and good performance in the selective hydrogenation of nitrobenzene to aniline (Conv. >99%; Sel. >99%). In addition, the fluid property of catalyst precursors and the geometry of the twin‐screw extrusion channel were studied, and the essence of this cyclic extrusion process is also discussed.

The mesoporous carbon-supported metal catalysts are important materials in heterogeneous catalysis. From the standpoint of process intensification, the current synthesis methods still suffer from several issues, such as the excessive use of toxic solvents, the time-consuming self-assembly process, and the difficulty of continuous production. Herein, we report a solvent-free and continuous route to synthesize mesoporous carbon-supported metal catalysts. Interestingly, the use of cyclic extrusion could promote the mixing, coordination, and assembly of catalyst precursors (tannin-metal salts-additives) by shearing and squeeze force. The as-made mesoporous carbon-supported nickel showed high surface areas (up to 512m2g-1), narrow pore size distribution (~10 nm), and good performance in the selective hydrogenation of nitrobenzene to aniline (Conv.>99%; Sel.>99%). In addition, the fluid property of catalyst precursors and the geometry of the twin-screw extrusion channel were studied, and the essence of this cyclic extrusion process is also discussed.