STUDY ON LANTHANUM MODIFIED Cu-SSZ-13 MOLECULAR SIEVE AS NH3-SCR CATALYST

Petroleum Processing and Petrochemicals ›› 2020, Vol. 51 ›› Issue (8): 50-55.

STUDY ON LANTHANUM MODIFIED Cu-SSZ-13 MOLECULAR SIEVE AS NH3-SCR CATALYST

Received:2020-03-30 Revised:2020-04-27 Online:2020-08-12 Published:2020-08-27
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Abstract

Abstract: The Cu-SSZ-13 molecular sieve was prepared by one-step process and then modified by lanthanum nitrate solution with different concentration. The modified molecular sieve were used as a NH3-SCR catalyst and characterized by XRD, BET, FT-IR, TPR and DRIFTS techniques. The NH3-SCR reaction results showed that the performance of La0.015-Cu-SSZ-13 catalyst was significantly better than that of Cu-SSZ-13 catalyst, and the NO conversion rate of La0.015-Cu-SSZ-13 catalyst was more than 90% in the temperature range of 175-450 ℃ with a good N2 selectivity. The NH3-SCR mechanism of La modified Cu-SSZ-13 is similar to Cu-SSZ-13 catalyst: ammonium nitrate, an intermediate species, is generated by surface ammonia species and nitrate species, and then ammonium nitrate is reduced by NO to generate N2 and H2O.

Key words: Cu-SSZ-13, La modification, NH3-SCR

CLC Number:

References

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