Tuning crystal size and inhibiting aggregation by adding guanidinoacetic acid in ZSM-5 zeolite synthesis for catalysing methanol-to-olefin reaction

Nanosized ZSM-5 zeolite with high-quality is highly desired in industrial application. This paper reports an approach of rapid synthesis of this type zeolite, being realized by crystallizing gels with the Si/Al atomic ratio of 12.5-80 at 170 celcius for 12 h under assistance of guanidinoacetic acid (GAA). As a result, the zeolite obtained from the synthesis possesses little crystal size (120-220 nm), high-quality and good monodispersity. Being associated with the superior morphology and structure, the zeolite displayed not only longer one-pass catalytic lifetime but also much higher regeneration stability in methanol-to-olefin reaction, comparing with the zeolite synthesized without GAA addition.