Hyd rot hermal synthes is of faujasite type zeolite in a
short crysta llizat ion period could be performed by preparing a
fresh aqueous nucleation solution mixed with an aluminosilicalc
gel into a teflon tube placed in thc stainless-steel microautoclave.
Effects of source of s ilica, sodium silicate, and colloidal silica and
also aging of nucleation solution were examined 10 prepare a
hig hly crys talline and pure fauja s ite. in all experiments
composition of the final gel was 3Na20,1 AI20 1,lOSi02, 160H20.
Mcthods of X-ray Diffraction, Scanning Electron Microscopy.
Energy Dispe rsive X-ray spectrometry associated with SEM,
infrared spectroscopy and Thermogravimetric Analysis were uesd
to study the crys tallinity and re lat ed properties. UV-VIS
spectrosco py were used to study the nucleation so lution .
Ultra-fine and pure clys tals of fauja s ite were obtained from a
nucleation so lution prepared from AI, NaOH and colloidal silica.
Average crystal size was l,um and calculated unil celJ formula
was Na491(AIOZ)49(Si02)l41j.255H20 Solid phase mate rials
precipitated from the aqueous nucleation solution arter seven
days, exami ned by X-ray difrreact ion showed btoaded peaks of
faujasite. This supports the hypot hesis that crystallization may
originated form liquid phase.