过氧化氢是应用广泛的绿色氧化剂，其主要生产方法是蒽醌法。该法的核心步骤是烷基蒽醌的氢化。目前普遍使用的Pd催化剂选择性较低，需要限制烷基蒽醌转化率低于60%和频繁更换活性氧化铝再生剂，才能维持较低的降解物量。这导致大量工作液无效循环、产生大量废氧化铝造成严重的环境污染等问题。因此，提高催化剂的选择性并维持其高活性，是解决上述问题的关键。本项目拟以介孔高度有序、热稳定性好的SBA-15分子筛为载体制备Pd催化剂。通过调控载体的孔尺寸和表面酸碱性及疏水性、利用有序介孔的限域作用固定Pd颗粒，强化反应/产物的扩散和吸/脱附性能、减小Pd的颗粒尺寸，进而提高催化剂的选择性和活性。拟通过系统研究SBA-15孔尺寸、表面酸碱性和疏水性以及Pd分布对催化剂的微介观结构及其烷基蒽醌加氢性能的影响规律，阐明载体结构和表面性质及Pd颗粒尺寸和分布的调控机制，发展高选择性、高活性负载型Pd加氢催化剂的制备方法。

Hydrogen peroxide is widely accepted as a green oxidant and, today, is almost exclusively produced by the sequential hydrogenation and oxidation of an alkyl-anthraquinone dissolved in a mixed solvent (working solution) known as the AO process. Catalytic hydrogenation of alkyl-anthraquinone in the working solution is a key step of the hydrogen peroxide production by the AO process. Since the Pd catalysts used commonly in industry show the relatively low selectivity, the hydrogenation are limited at the conversion of alkyl-anthraquinone lower than 60%, together with a requirement for periodic replacement of active alumina, to keep the smaller concentration of degradation products. It results in the use of a large amount of the working solution and formation of a large amount of spent active alumina which is harmful to environment. Hence, enhancement of the selectivity of catalysts, with maintenance of the high activity would be an effective route for solving the problems mentioned above. In this project, highly dispersed Pd catalysts will be prepared on hydrophobic SBA-15 silica with highly ordered mesopores and good thermal stability as supports for hydrogenation of 2-alkylanthraquinone. The pore size, acidity and alkalinity and hydrophilicity/hydrophobicity of SBA-15 will be adjusted to improve diffusion and adsorption of reactant as well as the diffusion and desorption of target product. And the confinement effect of ordered mesopores will be used to decrease the size of Pd particles. It is expected that all above would bring the benefits of enhancements in the selectivity and activity of catalyst. Also, the effects of the pore size and surface properties of SBA-15 (including acidity, alkalinity and hydrophilicity/hydrophobicity), and the distribution of Pd particles in the channels of support on the micro- and meso- structure of catalyst and hydrogenation behaviors of alkyl-anthraquinone will be systematically studied. The adjustment mechanism of the structure and properties of SBA-15 and size of Pd particles will be clarified. And the preparation method of Pd catalyst having the high selectivity and activity will be proposed through investigation works made in this project, which will give interesting information for the development of supported Pd catalysts with the high performance in large-scale production.