Abstract: The natural clinoptilolite as the object of study， which were modified by roasting at different temperature and time gradient， the changes of structural characteristics and ammonianitrogen removal ability in recycled water for zeolite after roasting modification were studied emphatically. The results showed that specific surface of zeolite increased， crystal structure， pore size distribution and cation exchange capacity of zeolite changed slightly， but ammoniumnitrogen removal rates increased from 5315% to 7213%， because of the remove of water and impurity in the pore channel for natural clinoptilolite in the suitable roasted temperature and time. While the zeolite roasted in overtemperature and excessive time， characteristic diffraction peak of natural zeolite became weaker， the framework collapsed， specific surface area and cation exchange capacity decreased dramatically， pore size distribution changed significantly， and ammoniumnitrogen removal ability decreased significantly.

Key words: natural zeolite, roasting modification, pore size distribution, ammoniumnitrogen, specific surface area