Progress in synthesis of A type and FAU type nano-zeolite and their formation mechanisms

Syntheses and formation mechanisms of nano-zeolite A type and FAU type crystals with tetramethylammonium hydroxide (TMAOH) as template or without any template were presented. In the latter case, only partial products were < 100 nm in particle sizes, and their distributions were broad, but for synthesis with TMAOH, the process was easy and controllable to obtain nano-zeolite A type and FAU type crystals with narrow particle size distributions. Based on the formation mechanism in the process without TMAOH, the nano-zeolite A type was crystallized from random aggregates of amorphous gel particles, while FAU type nano-zeolite crystals were randomly conglomerated from crystallites. In the process with TMAOH, both A type or FAU type nano-zeolite crystals grew up from discrete amorphous gel particles.