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Plausibility of potassium ion-exchanged ZSM-5 as soot combustion catalysts.

ABSTRACT: Potassium (K) ion-exchanged ZSM-5 zeolites were investigated for catalytic soot combustion. X-ray absorption fine-structure (XAFS), Raman, in situ IR and NH₃-temperature programmed desorption (NH₃-TPD) confirmed the location of K⁺ at the ion-exchanged sites. Temperature-programmed oxidation (TPO) reactions showed that K-ZSM-5 decreased ignition tempeatures of soot combustion and increased selectivity to CO₂. The improved activity for soot combustion by increasing K⁺-exchanged amounts via decreasing the Si/Al ratio reinforced the K⁺ ions participating in soot combustion. ¹⁸O₂ isotopic isothermal reactions suggested the activation of gaseous oxygen by the K⁺ ions. This demonstrated a new appliction of alkali metal exchanged zeolites and the strategy for enhancement of catalytic soot combustion activity.

SUBMITTER: Lu C

PROVIDER: S-EPMC5468242 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Plausibility of potassium ion-exchanged ZSM-5 as soot combustion catalysts.

Lu Chenxi C Liu Taizheng T Shi Qiaolan Q Li Qian Q Xin Ying Y Zheng Lei L Zhang Zhaoliang Z

Scientific reports 20170612 1

Potassium (K) ion-exchanged ZSM-5 zeolites were investigated for catalytic soot combustion. X-ray absorption fine-structure (XAFS), Raman, in situ IR and NH3-temperature programmed desorption (NH3-TPD) confirmed the location of K+ at the ion-exchanged sites. Temperature-programmed oxidation (TPO) reactions showed that K-ZSM-5 decreased ignition tempeatures of soot combustion and increased selectivity to CO2. The improved activity for soot combustion by ...[more]

PMID: 28607466

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