Pore Size Effects in Fischer Tropsch Synthesis over Cobalt-Supported Mesoporous Silicas

doi:10.1006/jcat.2001.3496

Journal of Catalysis

Volume 206, Issue 2, 10 March 2002, Pages 230-241

https://doi.org/10.1006/jcat.2001.3496 Get rights and content

Abstract

Pore size effects on Fischer Tropsch reaction rates and selectivities over cobalt catalysts were studied at atmospheric pressure using periodic (SBA-15 and MCM-41) and commercial mesoporous silicas as catalytic supports. The catalysts were characterized by nitrogen adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and oxygen titration. Fischer Tropsch reaction rates were found much higher on cobalt catalysts with the pore diameter exceeding 30 Å than on the narrow pore catalysts. A larger diameter of catalyst pores also led to significantly higher C₅₊ selectivities. The catalytic effects were interpreted in terms of different cobalt particle size and reducibility in the wide pore and narrow pore silicas. XRD and XPS showed that the size of supported cobalt species strongly depended on the pore size, increasing with increases in catalyst pore diameter. TGA and oxygen titration indicated higher extent of overall reduction of cobalt species in wide pore supports. Lower reducibility of small cobalt particles is likely to be one of the reasons responsible for the lower Fischer Tropsch reaction rates and higher methane selectivities on narrow pore cobalt catalysts.

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Regular ArticlePore Size Effects in Fischer Tropsch Synthesis over Cobalt-Supported Mesoporous Silicas

Abstract

J. Catal.

J. Catal.

J. Catal.

J. Catal.

Appl. Catal. A: General

Appl. Catal. A: General

Appl. Catal. A: General

Appl. Catal. A: General

Appl. Catal.

J. Catal.

Adv. Catal.

J. Catal.

Stud. Surf. Sci. Catal.

Microporous Mater.

Micro- porous Mesoporpous Mater.

J. Catal.

Catal. Today

J. Electron Spectrosc.

Appl. Catal.

J. Catal.

Appl. Catal. A

J. Electron Spectrosc. Relat. Phenom.

J. Electron Spectrosc.

Appl. Catal. A: General

J. Catal.

J. Catal.

J. Mol. Catal. A: Chemical

Chem. Eng. News

Regular Article
Pore Size Effects in Fischer Tropsch Synthesis over Cobalt-Supported Mesoporous Silicas