Study on the hydrothermal synthesis of zeolite and its crystal growth pathway

Abstract

In this study hydrothermal synthesis was used to synthesize zeolite By changing the temperature solid-liquid ratio alkali concentration holding time and addition of salts the mineral phase changes under different conditions were observed; this experiment was analyzed by X-ray powder diffractometer The crystal structure and long crystal change of the product and use the Raman spectrometer to obtain the characteristic vibration mode to verify the obtained mineral phase and understand the vibration mode change at different periods and then use the scanning electron microscope to observe the product morphology and the difference between different times An Atomic force microscope was used to scan its morphology to observe the surface of the product crystals of smaller size and to explore its crystal growth mechanism In addition the products obtained by hydrothermal synthesis using different natural materials under the same experimental conditions were also compared In the experiment the temperature holding time was changed and the process of crystal growth was observed as follows: Pumice→Albite→Phillipsite/Zeolite Na-P1→Zeolite Na-P1 It can be seen from the experiment that the overall product is mainly zeolite Na-P1 phillipsite is produced at high temperature and low alkali concentration and albite is always present in the reaction And use AFM to observe the zeolite Na-P1 to understand its crystal growth mode is spiral growth and its mechanism is poly-nuclear Birth and Spread Models This study explores the effect of crystallization time and various conditions on the zeolite crystallization process to understand the effect of the zeolites mineral formation mechanism

Date of Award	2020
Original language	English
Supervisor	Yen-Hua Chen (Supervisor)