采用纳米CaCO₃作为大孔模板剂、四丙基氢氧化铵（TPAOH）作为微孔模板剂，利用干胶转化法将CaCO₃加入分子筛TS-1的合成体系，使TS-1沿CaCO₃生长并形成核壳结构，再经过酸处理脱除CaCO₃，制备出大孔/微孔复合钛硅分子筛TS-1，其大孔尺寸约为60 nm。通过XRD、SEM、TEM、N₂物理吸附、UV-Vis光谱等表征手段对钛硅分子筛的孔道结构和钛物种状态进行表征，采用苯酚羟基化反应对所合成分子筛的催化性能进行评价。结果表明，CaCO₃的作用不仅能够构建大孔，并且可以改变钛物种的配位形式。由于降低了扩散阻力及抑制了锐钛矿型TiO₂的生成，该钛硅分子筛在催化苯酚羟基化反应中展现出优异的催化活性。

Macroporous/microporous titanium silicalite-1 is synthesized via a dry-gel conversion method by using nanoscale CaCO₃ as macroporous template and tetrapropylammonium hydroxide (TPAOH) as microporous template,in which CaCO₃ is added into the synthesis system of TS-1 molecular sieves,causing TS-1 to grow along CaCO₃ to form a core-shell structure.Finally,macroporous/microporous TS-1 are obtained after the dissolution of CaCO₃ by acid treatment.The size of microporous is around 60 nm.Samples are characterized by X-ray powder diffraction (XRD),scanning electron microscope (SEM),transmission electron microscope (TEM),N₂ physisorption and ultraviolet-visible diffused reflectance (UV-Vis) spectroscopy,and are evaluated in the hydroxylation of phenol.It shows that CaCO₃ can fabricate macropores and vary the coordination states of Ti species.TS-1 shows an excellent catalytic activity in the hydroxylation of phenol,due to the reduction of diffusion resistance and the inhibition of the formation of anatase TiO₂.

李同辉(1995-),男,硕士生,研究方向为大孔/微孔复合钛硅分子筛TS-1的合成及其催化应用,lth9655@mail.dlut.edu.cn