Chemical imaging of Fischer-Tropsch catalysts under operating conditions

Abstract

Multimodal x-ray imaging techniques reveal insight into the structure-function relationships in cobalt Fischer-Tropsch catalysts.

Intensification studies of heterogeneous catalysts: probing and overcoming catalyst deactivation during liquid phase operation

“…The second approach can lead to improved levels of time resolution, can provide information on non-linear effects, and also allows one to readily examine the performance of the catalyst as a function of bed length, which is particularly important given that each catalyst particle along the reactor axis is exposed to a different ratio of reactants and products. [104][105][106][107] In addition to these overarching challenges, several smaller hurdles also require study. The first is the development of alternative regeneration protocols.…”

Preparation of isolated Co3O4 and fcc-Co crystallites in the nanometre range employing exfoliated graphite as novel support material

“…A successful application of the modied PONKCS analysis 53 Even though the low temperature (<400 C) allotrope of metallic Co is reported to be hcp-Co for bulk phases, 81 the formation of single-phase fcc-Co without a (detectable) fraction of hcp-Co is in good agreement with literature. 84 Sintering of the nanoparticles during reduction of sample Co_7.6/EG in H 2 was identied ( Fig. 7a) even though the nanoparticles were expected to be rather isolated with relatively large inter-particle distances.…”

Structural Evolution of Highly Active Multicomponent Catalysts for Selective Propylene Oxidation

“…The high penetration of X-rays allows measurement of large samples, such as entire catalyst grains, combined with large fields of view and spatial resolution on the nm to µm scale. Furthermore, by applying computed tomography (CT) and three-dimensional (3D) image reconstruction, it is possible to retrieve chemical and structural data from the interior of catalyst bodies in a noninvasive manner [32][33][34]. Extending spatial resolution to 3D is a powerful advantage for the study of heterogeneous catalysts, which often contain delicate or fine structural features that are intimately linked to the catalyst function, as notably demonstrated for fluid catalytic cracking catalysts [35][36][37][38][39].…”