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煅烧高岭土与氢氧化钠的水热反应体系中，偏高岭石不仅为４Ａ沸石的形成提供了物质基础，而且为晶核的形成提供了有利界面。４Ａ沸石的晶核总是优先形成于发生了溶解的偏高岭石表面，而晶体生长的方式则受偏高岭石颗粒大小的影响。随着晶体的大量生长，偏高岭石逐渐消失，与此同时，产生了二次成核作用，晶体在先成的４Ａ沸石晶体表面生长，形成双晶。在整个反应过程中，液相中的［Ａｌ２Ｏ３］及［ＳｉＯ２］浓度的变化与４Ａ沸石晶体生成具有一定对应关系。这表明，偏高岭石不断溶解，固相的Ａｌ２Ｏ３·２ＳｉＯ２不断转化为液相的Ａｌ２Ｏ３和ＳｉＯ２。沸石晶体的生成是以液相各组分浓度的过饱和为动力的，为液相生成机理
Calcined kaolin and sodium hydroxide hydrothermal reaction system, metakaolin not only for the formation of 4A zeolite provides the material basis, but also provides a favorable interface for the formation of nuclei. The nuclei of 4A zeolite are always preferentially formed on the surface of metakaolinite that dissolves, while the crystal growth is influenced by the size of the metakaolin. With the mass growth of the crystal, the metakaolin gradually disappeared. At the same time, secondary nucleation occurred. The crystals grew on the surface of the previously formed 4A zeolite crystals to form twin crystals. Throughout the reaction, the concentration of [Al 2 O 3] and [SiO 2] in the liquid phase has a certain correspondence with the formation of 4A zeolite crystals. This indicates that the metakaolin continuously dissolves and the solid phase Al2O3 · 2SiO2 is continuously transformed into the liquid phase of Al2O3 and SiO2. The formation of zeolite crystals is based on the supersaturation of the concentrations of the liquid components as the driving force for the liquid phase formation mechanism