SYNTHESIS OF ZSM-5 ZEOLITE FROM VERY DENSE SYSTEMS - FORMATION OF PELLETED ZSM-5 ZEOLITE FROM (NA, LI, TPA, SI, AL) HYDROGELS

(Li,Na)-, Na-, and (Na,K)ZSM-5 zeolites are readily prepared in hydrothermal conditions at 170 + 2-degrees-C from highly dense gels of compositions aM2O bNa2O 2bTPABr bAl2O3 150 SiO2 490 H2O with M = Li, Na, or K; 0.9 less-than-or-equal-to a less-than-or-equal-to 8.82 and 1.66 less-than-or-equal-to b less-than-or-equal-to 15. In a quite narrow domain of composition, (Li,Na)ZSM-5 self-bonded pellets are formed from the same hydrogel with 8 less-than-or-equal-to a less-than-or-equal-to 9 and 14 less-than-or-equal-to b less-than-or-equal-to 16. The ca. 4-mu-m ZSM-5 crystallites are embedded in the remaining amorphous gel formed essentially by LiAlO2. The self-bonded pellets are also tested for attrition, pore-size distribution, and catalytic activity.