Regeneration of High Silica Zeolites via Advanced Oxidation Processes—A Preliminary Study About Adsorbent Reactivity Toward Ozone

• Published in: Chemical engineering research & design Vol. 81; no. 9; pp. 1193 - 1198
• Main Authors: Monneyron, P., Mathé, S., Manero, M.-H., Foussard, J.-N.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Rugby Elsevier B.V 01.10.2003; Institution of Chemical Engineers; Elsevier
• Subjects: adsorption; advanced oxidation processes (AOP); Applied sciences; catalytic decomposition; Chemical engineering; Chemical Sciences; Exact sciences and technology; high silica zeolites; Material chemistry; Miscellaneous; ozone; regeneration; high silica zeolites; advanced oxidation processes (AOP); adsorption; catalytic decomposition; regeneration; ozone; Ozonization; Reactivity; Adsorption; Adsorption capacity; Oxidation; Zeolite; Adsorbent; Advanced oxidation processes (AOP); Regeneration; Ozone; High silica zeolites
• ISSN: 0263-8762; 1744-3563
• DOI: 10.1205/026387603770866371

Aiming at regenerating adsorbents, the reactivity toward ozone of two high silica zeolites (HSZ), a dealuminated faujasite Y (Fau Y) and a silicalite (Sil Z), was investigated. In case of Fau Y, no physical adsorption occurred but a total degradation of ozone. This phenomenon was attributed to an active sites-role of silanol groups (SiOH), mainly developed by the dealumination step. In contrast, the ozone adsorption in the smaller channels of Sil Z was important (about 17 mmol g −1), but when a certain local concentration of ozone was reached, the ozone degradation became significant and increased up to 100%. The ozonated zeolites were regenerated in an oven. Whereas the regeneration was total at 773K, a treatment at 500K seemed insufficient since a co-adsorption phenomenon was observed with suspected nitrous oxides (NO 2) as a product of ambient nitrogen oxidation. Whereas the Fau Y was not affected at all by ozonation, the adsorption capacities of Sil Z zeolite were enhanced, and it exhibited a higher selectivity for polar compound. This was attributed to a surface modification, by highly reactive species generated during molecular ozone decomposition.