Seed-directed, rapid synthesis of MAZ-type zeolites without using organic structure-directing agent

• MAZ-type zeolites were obtained without using organic structure-directing agent.
• The “CBU Hypothesis” was applicable for the synthesis of 4R-rich zeolites.
• Intermediate seed addition enabled completion of crystal growth of the pure MAZ-type zeolite.
• Surprisingly short time of hydrothermal treatment.
• The product has a larger micropore volume and higher acidity than those of the seed crystals.

MAZ-type zeolites (omega) were successfully obtained for the first time using a seed-directed, organic structure-directing agent-free synthesis method according to the “Composite Building Unit Hypothesis” surprisingly in a short period (ca. 30 h) of hydrothermal treatment. The obtained product showed textural and acidic properties that were superior to the omega seed crystals synthesized using tetramethylammonium hydroxide as an organic structure-directing agent. Therefore, we believe the new technique is an efficient and environmentally friendly process for the preparation of MAZ-type zeolites for their use as adsorbents, catalysts, and so on. In addition, the “Composite Building Unit Hypothesis” was confirmed to be applicable for the synthesis of 4R-rich zeolites in the (Na, K)-aluminosilicate system.

Figure optionsDownload as PowerPoint slide