Characterizations and ion-exchange properties of zeolite NaA synthesized in a continuous process

Synthesis of zeolite through hydrothermal process has been commonly used for decades. However, slow crystallization kinetics and a limited thermo-dynamical stability of the target crystal phase are characteristic to zeolite formation, representing some of the key obstructions for fast zeolite synthesis. In this paper, the possibility of accelerating Zeolite NaA synthesis in a continuous flow reactor (CFR) was designed and installed. The CFR reduces the thermal lag by improving the crystallization rates of Zeolite NaA and decreasing the zeolite synthesis time. The optimal conditions for the synthesis of Zeolite NaA in the CFR were determined as a gel composition of Na2O:SiO2:Al2O3:H2O = 3.17 : 2 : 1 : 128, aging the gel mixture in 48 hours at ambient temperature. The synthesized powders were characterized by XRD, SEM. The results showed that the complete crystallization of typical cubic synthesized by the CFR was achieved at a synthesis temperature of 120°C during 5.5 mins with about 1 wt.% zeolite NaA see...