Hierarchical SAPO-18 molecular sieve was successfully post-synthesized in the alkaline tetraethyl ammonium hydroxide (TEAOH) solution and hydrochloride (HCl) acid solution. In the TEAOH solution, preferential dissolution occurs surrounding the defect sites in a controlled manner, leading to hierarchical SAPO-18 with well-preserved chemical compositions and crystallinities. In acidic solution, the dissolution is revealed to be sensitive to both the defects and the chemical compositions (selective dissolution of the Si-O-Al domains), which cooperatively contribute to the generation of meso-/macropores in the crystals. The crystallization of SAPO-18 precursor is thus inferred to proceed via an oriented nanoparticle attachment mechanism in the early stage. The twinning and intergrowth of nanoparticles occur in an ordered way, leading to the oriented arrangement of the crystallite boundaries. The defects located at the intergrowth interface are prone to acid/alkaline attacks, and play crucial role in the development of hierarchical pore systems. The hierarchical SAPO-18 sample exhibits excellent catalytic reaction performance in the liquid phase benzylation reaction of benzene and benzyl alcohol.

在碱性四乙基氢氧化铵（TEAOH）溶液和盐酸盐（HCl）酸性溶液中成功地完成了分级SAPO-18分子筛的合成。在TEAOH溶液中，以受控方式在缺陷部位周围发生优先溶解，从而导致具有良好保留的化学成分和结晶度的分层SAPO-18。在酸性溶液中，溶解表现出对缺陷和化学成分（Si-O-Al域的选择性溶解）均敏感，而化学成分则共同有助于晶体中介孔/大孔的产生。因此，可以推断SAPO-18前体的结晶是在早期通过定向的纳米粒子附着机制进行的。纳米粒子的孪生和共生以有序的方式发生，导致微晶边界的定向排列。位于共生界面的缺陷易于受到酸/碱的侵蚀，并且在分层孔隙系统的发展中起着至关重要的作用。分层的SAPO-18样品在苯和苯甲醇的液相苄基化反应中显示出优异的催化反应性能。