Investigation of the problems with using gas adsorption to probe catalyst pore structure evolution during coking

N. Gopinathan, M. Greaves, J. Wood, S.P. Rigby

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

A common approach to try to understand the mechanism of coking in heterogeneous catalysts is to monitor the evolution of the pore structure using gas adsorption analysis of discharged pellets. However, the standard methods of analysis of gas adsorption data, to obtain pore-size distributions, make the key assumption of thermodynamically-independent pores. This assumption neglects the possibility of co-operative adsorption phenomena, which will shown to be a critical problem when looking at coking catalysts. In this work the serial adsorption technique has been used to detect and assess the extent of co-operative effects in adsorption within coking catalysts. The reaction of decane over a hydroprocessing catalyst was used as a case study. It has been shown that the conventional analysis method would lead to a flawed picture of the pore structure changes during the coking process. For the case-study considered in this work, it was found that co-operative adsorption effects meant that 26% of the measured adsorption was occurring in pores up to three times larger than the size conventional analysis would presume. The serial adsorption technique was thus shown to provide important additional information on pore structure evolution during coking. A study of the kinetics of adsorption has been used to infer information about the general spatial location of the coking process within a pellet.
Original languageEnglish
Pages (from-to)234-240
JournalJournal of Colloid and Interface Science
Volume393
Issue number1
DOIs
Publication statusPublished - 1 Mar 2013

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Gas adsorption
Coking
Pore structure
Adsorption
Catalysts
Pore size
Kinetics

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Investigation of the problems with using gas adsorption to probe catalyst pore structure evolution during coking. / Gopinathan, N.; Greaves, M.; Wood, J.; Rigby, S.P.

In: Journal of Colloid and Interface Science, Vol. 393, No. 1, 01.03.2013, p. 234-240.

Research output: Contribution to journalArticle

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