Abstract: On the iron containing zeolite molecular sieves (iron-zeolite),it′s proposed to determine Si by using silicomolybdate blue photometry,to determine the combined amount of Al and Fe by EDTA-Pb(NO₃)₂ titration,and to determine iron by sulfosalicylic acid-spectrophotometry.Finally the silicon,aluminum,and iron contents could be calculated,and the Si/Al ratio could be obtained.Experiments proved that this method was simple and feasible.Determination of Si/Al ratio could provide important reference index and theoretical foundation for zeolite performance and it could also help to decide what kind of molecular sieve can meet the requirements.In addition,the chemicals required in this experiment are very common,and the experiment can be carried out in general laboratory,so it has some obvious advantages in economic costs and application scope.Also the reference value is significant.

Key words: zeolite molecular sieve, iron, Si/Al ratio