以一种直径约170 nm的PMMA微球胶体晶体为模板,复制出孔径约为95 nm的三维有序大孔SiO2,以这种大孔结构为载体,采用浸渍-焙烧法制备了三维有序大孔负载的Pt-SO4 2-/TiO2固体超强酸催化剂.探讨了TiO2负载量对三维有序大孔结构的影响.采用SEM、XRD、N2吸附-脱附实验对其大孔结构进行了表征.结果表明,适宜的TiO2负载量为30％(质量分数),太低,酸性不强,太高,易产生大孔的堵塞.负载后的大孔孔径约为75nrn,呈现一种厚壁的球形大孔结构.与通常的三维有序大孔材料(孔径大于300 nm)相比,这种孔径小化的大孔材料具有稳定性高和表面积大的特征.以乙酸和正丁醇的液相酯化反应为探针反应,发现这种大孔固体超强酸催化剂可以明显提高其催化活性.
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