Attempts to Synthesize Zeolitic Composites from Stellerite

Abstract

A feasible method to synthesize NaA and NaY zeolite from stellerite, the very cheap raw material found in China, was reported in this article to reduce the cost of zeolite synthesis for the first time. After stellerite is calcined above 973 K with sodium carbonate, this natural zeolite can be slowly dissolved in alkali solution and partly forms the gels, then transforms to zeolite NaA or NaY by structural rearrangement. The effect of synthetic conditions such as the ratio of different cation used in the reactive mixture on the resulting zeolite is examined. Furthermore, a new NaA/MCM-41 composite possessing both micropore and mesopore is synthesized by adding the NaA zeolite into the synthetic system, and the impact of zeolite additive on the pore structure of final porous composite is also explored.

Keywords:

• Alkali cation
• Infrared (IR)
• MCM-41 mesoporous silica
• Mesopore
• Micropore
• NaA zeolite
• NaY zeolite
• Natural zeolite
• NaA/MCM-41 composite
• Potential additive in detergents
• Scan electron microscopy (SEM)
• Stellerite
• Structural rearrangement
• Synthesis
• Transmission electron microscopy (TEM)
• X-ray diffraction (XRD)

ACKNOWLEDGMENTS

This research project is financially supported by the National Natural Science Foundation of China (20273031, 20373024, and 20673053), and British America Tobacco (BAT) as well as the Analysis Center of Nanjing University. Dr. Kai Shen from Nanjing University of Aeronautics and Astronautics is acknowledged for the fulfillment of TEM experiments.

Notes

; ^bBJH average pore diameter; ^cThe wall thickness was calculated as: a _o- pore diameter.