Here, we investigate the effects of fluoride concentration on the phase selectivity of crystallization in (alumino)silicate synthesis mixtures containing a series of N-alkyl-N-methylpiperidinium ions, where alkyl is methyl to hexyl, as organic structure-directing agents (OSDAs). Considerable diversity in the phase selectivity was observed when the HF/OSDA ratio in synthesis mixtures is 2.0 or higher. Using this excess fluoride approach, we synthesized five different aluminosilicate zeolites (i.e., EMM-10P, EU-1, MCM-22P, ZSM-12, and ZSM-58) that did not crystallize under the normal F⁻ concentration conditions (HF/OSDA = 1.0). Our synthesis results also reveal that the same zeolite phase (i.e., levyne, nonasil, octadecasil, or ZSM-5) can crystallize over a wide range (0.5–2.0) of HF/OSDA ratios. More interestingly, F⁻ concentration in the synthesis mixture was found to influence the crystal size and framework Al distribution of levyne.

在这里，我们研究了氟化物浓度对含有一系列N-烷基-N-甲基哌啶鎓离子的（铝）硅酸盐合成混合物中结晶相选择性的影响，其中烷基是甲基到己基，作为有机结构导向剂（OSDA） ）。当合成混合物中的 HF/OSDA 比率为 2.0 或更高时，观察到相选择性的显着差异。使用这种过量氟化物的方法，我们合成了五种不同的铝硅酸盐沸石（即 EMM-10P、EU-1、MCM-22P、ZSM-12 和 ZSM-58），它们在正常 F 下不会结晶^-浓度条件 (HF/OSDA = 1.0)。我们的合成结果还表明，相同的沸石相（即 levyne、nonasil、octadecasil 或 ZSM-5）可以在很宽的 HF/OSDA 比率范围 (0.5–2.0) 内结晶。更有趣的是，发现合成混合物中的F ^-浓度会影响 levyne 的晶体尺寸和骨架铝分布。