Cu-SAPO-34 received considerable attention due to their outstanding NH3-SCR activity in a wide temperature window and high hydrothermal stability. The“one-pot” synthesis method whichemploys copper-tetraethylenepentamine (Cu-TEPA) complex as a template and copper source to synthesize Cu-SAPO-34 is convenient and easy to be operated. Unfortunately, the Cu-TEPA tends to direct SAPO-34s with high Si and Cu contents and abundant Si islands resulting in inferior catalytic performance and hydrothermal stability.
Recently, a research group of Prof. Liu zhongmin et al. fromDalian Institute of Chemical Physics of Chinese Academy of Sciences provided a new reconstruction strategy to hydrotermally synthesize Cu-SAPO-34 where Cu-rich SAPO-34 directed by Cu-TEPA complex was used as a precursor and copper source to assist the crystallization of Cu-SAPO-34. The synthesized Cu-SAPO-34 exhibited high catalytic activity and enhanced hydrothermal stability for the selective catalytic reduction of NOxby NH3(NH3-SCR).
This work was published inChinese Jouranl of Catalysison September 5.
The Cu-SAPO-34 precursor restricted the template role of Cu-amine complex effectively and thus allowed an easy control on the Cu and Si contents as compared to the previously reported “one-pot” synthesis method. Characterization results revealed that Si(4Al) environment dominated the synthesized Cu-SAPO-34s and the high-temperature hydrothermal treatment increased the isolated Cu2+content slightly. In addition, the investigation indicated that the acidity of Cu-SAPO-34 had great effect on the NH3-SCR activity and hydrothermal stability. Weaker acidity was beneficial to the low-temperature NH3-SCR activity.
These results implied that Cu-SAPO-34 catalyst prepared by reconstruction method was a promising candidate for the NH3-SCR process.
This work was supported byNational Natural Science Foundation of China and Key Research Program of Frontier Sciences, CAS. (Text by Sun Lijing)
A reconstruction strategy for the synthesis of Cu-SAPO-34 with excellent NH3-SCR catalytic performance and hydrothermal stability. Lijing Sun, Miao Yang, Yi Cao, Peng Tian*, Pengfei Wu, Lei Cao, Shutao Xu, Shu Zeng, Zhongmin Liu, Chinese Journal of Catalysis, 41(9):1410-1420, 2020.
