This paper is a combined preparation and catalysis study, which explores the relationship between catalyst preparation and performance, in particular how the conditions of manufacture impact on catalyst deactivation. The commercialy important reaction of toluene disproportionation (TDP) was stuided using catlaysts based on zeolite EU-1. This report describes initial results from a screening study, where it was found that different samples of EU-1 decayed at markedly different rates; these were samples of different compsoitions synthesised at different temperatures for different periods of time. The decay characteristics are rationalised in terms of synthesis reaction over-run during which there is a marked variation in both the pH of the reaction mixture and the surface composition of the isolated material, as determined by x-ray photoelectrom spectroscopy (XPS). THis over-run phenomena, not previously reported for high-silica zeolites, is related to synthesis temperature (and composition) and is likely to be important for other zeolite catalysts.
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