Abstract: To explore the way which can efficiently utilize coal gangue,the 4A zeolite was synthesized with alkali fusion-hydrothermal method at low temperature was characterized by XRD and SEM using the Coal Gangue of Inner Mongolia as the raw material.The composition ratio of the raw material was n(SiO₂)∶n(Al₂O₃)=1.9,n(Na₂O)∶n(SiO2)=2.2,n(H₂O)∶n(Na₂O)=30,using the guiding agent,crystallization temperature of 50 ℃ and crystallization time of 30 h,the calcium ion exchange capacity of the product achieves 318.00 mg/g;The XRD and SEM analysis showed that the 4A zeolite had high crystallization and degree of crystallinity,the structure of cubic crystal was complete,angular and the particle size was about 2 μm with the high purity and moderate porosity.The 4A zeolite was in accordance with the technical requirements specified in the 1768-2003 QB/T 4A Zeolite for detergents.

Key words: Coal gangue, Low temperature alkali fusion, Hydrothermal crystallization, 4A zeolite