Chem. J. Chinese Universities ›› 2023, Vol. 44 ›› Issue (10): 20230034.doi: 10.7503/cjcu20230034

• Articles: Inorganic Chemistry • Previous Articles     Next Articles

Rapid Synthesis of SSZ-13 Zeolite via Interzeolite Transformation of L Zeolite and Formation Mechanism of Its Hollow Structure

ZHANG Zongyang, LI Yuping(), ZHANG Ruoxi, LIU Yufeng, CHEN Ze, HAN Lina, HAN Peide   

  1. College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China
  • Received:2023-01-31 Online:2023-10-10 Published:2023-04-07
  • Contact: LI Yuping E-mail:liyuping@tyut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21978195);the Natural Science Foundation of Shanxi Province, China(201701D121024)

Abstract:

Using NNN-trimethyl-1-amantamine hydroxide(TMAdaOH) as organic structure directing agents, SSZ-13 zeolite was synthesized by direct conversion of zeolite L with a low SiO2/Al2O3 ratio(SAR) by adding additional Si source at 180 ℃. The crystallization process was tracked by XRD, FTIR, SEM, N2 adsorption-desorption and HRTEM characterization. It was found that the crystallization rate was greatly accelerated at 180 ℃, and highly crystalline SSZ-13 was synthesized after 4.5 h of crystallization. At the same time, it was noted that hollow crystals appeared during the crystallization process under this experimental condition. The formation mechanism of the hollowing structure was further explored by combining with SEM-EDS characterization. It was found that during the process of slow degradation of zeolite L and the simultaneous rapid nucleation and growth of SSZ-13, the SAR in the middle of zeolite crystals was higher than that at the edge, that is, the SAR distribution in the whole crystal was uneven. Silicon-rich crystal nucleus can be selectively desilicated under alkaline conditions, leading to the hollow phenomenon. Finally, the catalytic performance of the hollow samples after copper ion exchange in NH3 selective catalytic reduction(NH3-SCR) reaction of NO x was investigated, and the catalytic results were analyzed in combination with the characterization of NH3 temperature-programmed desorption(NH3-TPD) and H2 temperature-programmed reduction(H2-TPR).

Key words: SSZ-13 zeolite, Interzeolite transformation, L zeolite, Hollow zeolite, NH3 selective catalytic reduction(NH3-SCR) reaction

CLC Number: 

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