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ZSM-22 was synthesized using various sources of silica, organic template 1,6-diaminohexane, under hydrothermal conditions, with and without agitation during crystallization. Subsequently, the crystallized material was used as seeds to accelerate the crystallization process. Characterization of the ZSM-22 samples was performed by XRD, ATG/DTG and FT-IR. It was found that it is possible to synthesize ZSM-22 employing colloidal silica and pyrolytic silica as silicon sources only if the system is stirred during crystallization. The crystallization time for these systems was 13 hours, longer times of crystallization do not significantly increase the crystallinity of the sample. The addition of seeds significantly accelerates the crystallization of ZSM-22, reducing the crystallization time to only 7 hours, with stirring and with systems employing colloidal silica.

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INTRODUÇÃOAs zeólitas são aluminossilicatos cristalinos contendo canais microporosos e/ou cavidades em sua estrutura. Sua rede cristalina é constituída de tetraedros de SiO 4 e AlO 4 ligados por átomos de oxigênio, formando assim uma rede tridimensional de tetraedros TO 4 [1]. O estudo destes materiais desperta cada vez maior importância devido algumas de suas propriedades intrínsecas (estabilidade térmica, acidez, entre outras), e também devido a algumas de suas aplicações como trocadores iônicos, adsorventes e catalisadores na indústria petroquímica [2].A técnica de difração de raios X (DRX) é a mais indicada