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Nitrobenzene liquid-phase catalytic hydrogenation is commonly regarded as one of the most effective technologies for aniline production. The traditional granular catalysts have the disadvantages that the reactor bed pressure drop is large and the mass transfer efficiency between gas and liquid phases is low. In this study, a novel structured mesh-type Pd/γ-Al₂O₃/Al catalyst was prepared by anodic oxidation and pore structures of γ-Al₂O₃/Al supports were constructed by acid pore-widening treatments. The results showed that acid pore-widening treatments can improve the pore size of γ-Al₂O₃/Al supports; the support with HNO₃ pore-widening treatment exhibited the largest pore size, being enlarged from 3.7 nm to 4.6 nm. The Pd/γ-Al₂O₃/Al catalysts prepared with different acid pore-widening treatment supports contribute to the increased active metal Pd loading, more Pd⁰ content, and better dispersion of the Pd particles. The catalyst prepared with HNO₃ pore-widening treatment support exhibited the largest active metal Pd loading, enlarging from 1.82% to 1.95%, the largest Pd⁰ content being enlarged from 52.1% to 58.5% and the smallest Pd particle size being reduced from 103 nm to 41 nm, resulting in the highest nitrobenzene conversion, increasing from 67.2% to 74.3%. Eventually, we calculated that the pressure drop of structured catalysts was 1/72 of that of granular catalysts, resulting in a better diffusion of the H₂ through nitrobenzene solution to active sites on the catalyst surface and a significant increase in the catalytic activity. Full article

Steam activation treatments were introduced in the preparation of activated carbon fiber from liquefied wood (LWACF), to enlarge its specific surface area and develop the pore size distribution. With increasing activation time, the average fiber diameter of LWACF decreased from 27.2 µm to 13.2 µm, while the specific surface area increased from 1025 to 2478 m²/g. Steam activation predominantly enhanced the development of microporosity, without significant pore widening. Prolonging the steam activation time exponentially increased the removal efficiency of Cu²⁺ at a constant adsorbent dose, as a result of an increase in the number of micropores and acidic-oxygenated groups. Moreover, for LWACF activated for 220 min at 800 °C, the removal efficiency of Cu²⁺ increased from 55.2% to 99.4%, when the porous carbon fiber dose went from 0.1 to 0.5 g/L. The synthesized LWACF was proven to be a highly efficient adsorbent for the treatment of Cu²⁺ ion-contaminated wastewater. Full article