Abstract: The zeolite was synthesized by the hydrothermal method and with shell furnace coal fly ash.NaA zeolite was pre- pared with 1.7 of Si/Al（amount-of-substance ratio） and synthetic conditions were optimized by single factor experiment and orthogonal experiments.The optimum conditions were determined to be 1 mol/L of NaOH，100 ℃ of crystallization tempera- ture，7 h of crystallization time，and 5∶1（mL/g） of liquid-to-solid ratio.The denitrification ability of the synthesized NaA zeo- lite under these conditions was the best and the removal rate of ammonia nitrogen reached 74.62%.The orthogonal experiment results showed that the influence of different factors on denitrification performance of NaA zeolite was alkali concentration> crystallization temperature>liquid-to-solid ratio>crystallization time.Results showed that the product′s crystallinity was large and its purity was high.Crystal morphology was complete and inerratic.The pore arrangement of zeolite was in order and closely.It can be used in the treatment of ammonia nitrogen wastewater.

Key words: shell furnace coal fly ash, hydrothermal synthesis, zeolite, ammonia nitrogen wastewater