Chelating agent, including NaF, Na₄EDTA, etc., has been introduced into the alkaline treatment of ZSM-5 zeolite. Compared with the general aqueous alkaline solution, all of the resulting chelating-alkaline media give similar alterations to the porosities. Regardless of the relative accessibility of chelating agent to the zeolite micropores, the maximum distribution of mesopore obviously shifts to the smaller dimension. Such shift in mesopore distribution is associated with the equilibrium between surface/interface etching and shielding, which is inherently directed by the transition of framework Al species. The spontaneous interplays between framework Al species and alkaline solution are altered due to the concurrent presence of chelating agent. It has been proved that the chelating agent join the transition by a joint complexation with OH⁻ anions and the released aluminum cations. The resulting ternary intermediates ([Al(OH)_nL_m]^y−) are proposed to be responsible for the alterations to the porosities due to their expanded shielding scope on the etched surface/interface. The corresponding steric or charge effect from chelating agent has been ascertained by the designed comparative treatment experiments. The used methodology and the related fundamental understandings may enrich the tailoring tool boxes for the hierarchical zeolites.

螯合剂，包括 NaF、Na ₄EDTA等已被引入到ZSM-5沸石的碱处理中。与一般的碱性水溶液相比，所有得到的螯合碱性介质对孔隙率都有相似的改变。无论螯合剂对沸石微孔的相对可及性如何，中孔的最大分布明显向更小尺寸移动。中孔分布的这种变化与表面/界面蚀刻和屏蔽之间的平衡有关，这本质上是由框架 Al 物质的转变所引导的。由于螯合剂的同时存在，骨架铝物种和碱性溶液之间的自发相互作用发生了变化。已经证明螯合剂通过与 OH ^-的联合络合来加入转变阴离子和释放的铝阳离子。所得的三元中间体（[Al(OH) _n L _m ] ^y-）被认为是造成孔隙率变化的原因，因为它们在蚀刻表面/界面上扩大了屏蔽范围。螯合剂的相应空间或电荷效应已通过设计的比较处理实验确定。所使用的方法和相关的基本理解可能会丰富分级沸石的裁剪工具箱。