Multiscale multi-technique characterization of the pore network structure for nickel-iron-based industrial catalysts

Abstract

Pore structures, critical for catalyst mass transfer efficiency and active site accessibility, present a cross-scale complexity that challenges conventional characterization methods. This study integrated synchrotron multiscale CT, mercury intrusion porosimetry, and nitrogen adsorption to achieve a comprehensive, full-scale analysis of the pore network in Ni-Fe industrial catalysts, spanning 1.48 nm to 365 μm. Through 3D reconstruction, the study unveiled complex structural features, such as cavity structures and “ink-bottle” pores, which are hard to capture with traditional single techniques. Comparing results from the three methods clarified the limitations of conventional approaches in analyzing complex pore sizes. Based on the pore characteristics of Ni-Fe catalysts, this study proposes a hierarchical pore structure design to optimize mass transfer and enhance performance. The integration of multiple techniques achieved complementary advantages, and the in-depth analysis based on this multimodal approach provides quantitative guidance for catalyst optimization and preparation. The findings offer a theoretical basis for developing more efficient and stable industrial catalysts and advancing catalyst design toward a digital and rational approach.

Keywords

Synchrotron radiation / multiscale CT / Ni-Fe based catalyst / MIP / pore size distribution

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