Master of Science
Dr. Yining Huang
Phase-pure high silica zeolites have been synthesized using different deep eutectic solvents for the first time. ZSM-5 was made in tetrapropylammonium bromide/pentaerythritol. The reaction is affected by the amounts of seeding, water content, and organic structure-directing agent (SDA). Sodalite and ZSM-39 were prepared in tetramethylammonium chloride (TMACl)/1, 6-hexanediol by using the mineralizing agents NaOH and NH4F, respectively. In urea/choline chloride, ZSM-5, Beta, ZSM-39, and ZSM-11 were made by using different organic SDAs in the presence of fluoride. The reaction temperature and the choice of organic SDA affect the type of structures being produced.
The crystallization of ZSM-39 in TMACl/1, 6-hexanediol was studied by powder X-ray diffraction, NMR spectroscopy, and SEM. Amorphous silica first arrange themselves around the TMA+ and then reorganize to form the larger cages. The larger cages are joined together as the smaller cages are formed, trapping the F- in the framework.
Lin, Zheng Sonia, "Ionothermal Synthesis of High Silica Zeolites in Deep Eutectic Solvents (DES)" (2012). Electronic Thesis and Dissertation Repository. 722.