The study on green rapid synthesis of Cu-ZK-5 zeolite catalyst in NH3-SCR reaction

The ZK-5 zeolite was synthesized using an eco-friendly and rapid method by incorporating H2O2 and seeds, omitting the traditional organic template. And the rapidly synthesized Cu-ZK-5 catalyst exhibit excellent NH3-SCR performance and hydrothermal stability. The synthesis mechanism is hypothesized to result from the synergistic effects of the seeds and H2O2. The seeds inclusion could avoid non-uniform nucleation during the synthesis process and promote the crystal growth and crystallization process by providing a surface for crystal growth. The innovative addition of H2O2 facilitated the formation of Si-O-Si bonds, thereby accelerating the zeolite crystallization process initiated by the seeds, which resulted in a more rapid incorporation of Si into the zeolite framework. Furthermore, characterization results indicated that the rapidly synthesized samples were rich in acidic sites and active Cu2+ species, with excellent NO adsorption capacity. These features likely contributed to the enhanced NH3-SCR performance and hydrothermal stability.