Impact of residual sodium cations in azonia-spiro templates on the formation of large and extra-large pore zeolites

Azonia-spiro compounds have been reported as organic templates for synthesizing many extra-large pore high silica zeolites, often isomorphically substituted by germanium. However, these are usually obtained in the presence of sodium hydroxide, leading to persisting ions final products. Sodium cations may compete with azonia-spiro organics during zeolite synthesis. Therefore, effect any residual on synthesis results needs be investigated. This work documents formation using four structurally similar templates. Different silicogermanate zeolites (UTL, an unknown zeolitic phase, etc.) were formed absence cations. Notably, syntheses UTL and siliceous MTW azonia-spiro[4,6] [6,6] first time. Controlled amounts chloride added crystallization mixtures without hydroxide. In 0.005–0.1 mol/L Na+, dominant phases. Further increasing Na+ concentration 0.152 0.317 mol/L, phase inhibited favor a dense sodiumgermanate (Na4Ge9O20). Moreover, next also influence morphologies zeolites. The observed sensitivity even traces therefore has impact protocols large highlights how small, overlooked, factors inorganic material can drastically change outcome.