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Nanoscale Chemical Imaging of an Individual Catalyst Particle with Soft X-ray Ptychography.

ABSTRACT: Understanding Fe deposition in fluid catalytic cracking (FCC) catalysis is critical for the mitigation of catalyst degradation. Here we employ soft X-ray ptychography to determine at the nanoscale the distribution and chemical state of Fe in an aged FCC catalyst particle. We show that both particle swelling due to colloidal Fe deposition and Fe penetration into the matrix as a result of precracking of large organic molecules occur. The application of ptychography allowed us to provide direct visual evidence for these two distinct Fe-based deactivation mechanisms, which have so far been proposed only on the basis of indirect evidence.

SUBMITTER: Wise AM

PROVIDER: S-EPMC4822187 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Nanoscale Chemical Imaging of an Individual Catalyst Particle with Soft X-ray Ptychography.

Wise Anna M AM Weker Johanna Nelson JN Kalirai Sam S Farmand Maryam M Shapiro David A DA Meirer Florian F Weckhuysen Bert M BM

ACS catalysis 20160226 4

Understanding Fe deposition in fluid catalytic cracking (FCC) catalysis is critical for the mitigation of catalyst degradation. Here we employ soft X-ray ptychography to determine at the nanoscale the distribution and chemical state of Fe in an aged FCC catalyst particle. We show that both particle swelling due to colloidal Fe deposition and Fe penetration into the matrix as a result of precracking of large organic molecules occur. The application of ptychography allowed us to provide direct vis ...[more]

PMID: 27076990

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