Zeolite synthesis in presence of hexamethonium ions

The role played by hexamethonium ions in the synthesis of one-dimensional ZSM-48 and EU-1 zeolitic structures is investigated. A systematic study is carried out to determine the factors influencing the preferential crystallization and/or co-crystallization of ZSM-48 and EU-1 from a sodium-hexamethonium-silica-alumina hydrogel. The influence of sodium and organic content and the Si/Al ratio in the initial hydrogel is specifically examined. An explanation is proposed for the accommodation of the hexamethonium ions in the different zeolitic frameworks of ZSM-48 and EU-1. (c) 2008 Elsevier B.V. All rights reserved.