Maintaining an optimized pore structure of the spherical alumina support after hydrothermal treatment is crucial for catalytic efficiency, as the pore structure is intricately linked to the dispersion of catalytically active components and the diffusion of reactants. In this work, a unique mesoporous–macroporous spherical γ-Al₂O₃ material (γ-Al₂O₃-CD) with a reduced amount of surface hydroxyl groups was successfully synthesized to address pore blockages and enhance hydrothermal stability. Dodecane and hydrophilic-modified activated carbon were used as dual-template agents and, as a result, γ-Al₂O₃-CD exhibits a distinctive mesoporous–macroporous structure, which is beneficial for specific surface area and stability. The mercury intrusion porosimetry (MIP) specific surface area is measured to be 256 m²·g^–1, with a considerable pore volume of 0.62 mL·g^–1 and an impressive porosity of 58.4%. In contrast, untreated γ-Al₂O₃ possesses only a specific surface area of 204 m²·g^–1 and a pore volume of 0.40 mL·g^–1. Additionally, the abundant pore structure greatly facilitates precursor dehydration, leading to the formation of γ-Al₂O₃. Remarkably, the γ-Al₂O₃ content in γ-Al₂O₃-CD reaches an impressive 70.7%, with a chemical shift of μ²-OH at 1.31 ppm, resulting in a decreased number of surface hydroxyl groups and ultimately enhanced hydrothermal stability. Even after a 120 h hydrothermal treatment, the MIP specific surface area remains virtually unchanged at 255 m²·g^–1.

中文翻译：

---

双模板耦合法制备具有增强水热稳定性的介孔-大孔球形氧化铝


水热处理后保持球形氧化铝载体的优化孔结构对于催化效率至关重要，因为孔结构与催化活性组分的分散和反应物的扩散有着错综复杂的联系。在这项工作中，成功合成了一种独特的介孔-大孔球形 γ-Al₂O₃ 材料 （γ-Al₂O_3-CD），其表面羟基含量降低，解决了孔隙堵塞问题并增强了水热稳定性。十二烷和亲水改性活性炭用作双模板剂，因此，γ-Al₂O_3-CD 表现出独特的介孔-大孔结构，有利于比表面积和稳定性。经测得的压汞孔隙度计 （MIP） 比表面积为 256 m²·g^–1，孔隙体积为 0.62 mL·g^–1，孔隙率高达 58.4%。相比之下，未经处理的 γ-Al₂O₃ 仅具有 204 m²·g^–1 的比表面积和 0.40 mL·g^–1 的孔体积。此外，丰富的孔隙结构极大地促进了前驱体脱水，导致 γ-Al₂O₃ 的形成。值得注意的是，γ-Al₂O_3-CD 中的 γ-Al₂O₃ 含量达到了令人印象深刻的 70.7%，μ^2-OH 的化学位移为 1.31 ppm，导致表面羟基数量减少，最终增强了水热稳定性。即使在 120 h 的水热处理后，MIP 比表面积在 255 m²·g^–1 时几乎保持不变。