Synthesis of ITQ-21 in OH– media

ITQ-21 has been synthesized from F– free gels; aluminum can be incorporated and this does not affect the rate of nucleation. The introduction of stoichiometric amounts of NH4F with respect to the number of double four rings (D4R) present in the structure leads to an increase in the nucleation and crystallization rate with a quantitative incorporation of fluoride ions into the solid.