SYNTHESIS AND CHARACTERIZATION OF SILICIOUS MORDENITE

Mordenite, a zeolite, is widely used as adsorbent, catalyst, catalyst support and ion exchanger. The thermal stability and acid resistant ch aracteristics of the zeolite are found to increase with increase of th e silica alumina ratio (SAR). Direct synthesis of silicious mordenite using sodium polysilicate, aluminium sulphate and sodium hydroxide wit hout involving templating agent and ageing and their characteristics a re presented in this communication. Mordenite having SAR in the range of 11.65-16.07 crystallizes within 6-14 h in the temperature range of 165-185 degrees C. The SAR of the mordenite increases with increase of this ratio and decrease of the Na2O:SiO2 ratio in the starting compos ition. Amorphous material and wairakite are formed when Na2O:SiO2 rati o is in the range of 1.96-1.45. Prolonging the reaction time beyond co mplete crystallization leads to mordenite degradation and formation of amorphous material. The mordenite formed have been characterized by c hemical analysis, optical microscopy, particle size analysis, XRD, IR, NMR and thermal analysis.