Title: | Effect of ball milling on the catalytic activity of cryptomelane for VOC oxidation |
Author(s): | Santos DFM; Soares O; Figueiredo JL; Pereira MFR; |
Address: | "Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Porto, Portugal" |
DOI: | 10.1080/09593330.2018.1491639 |
ISSN/ISBN: | 1479-487X (Electronic) 0959-3330 (Linking) |
Abstract: | "Cryptomelane-type manganese oxides prepared by a solvent-free method were evaluated as catalysts for the oxidation of ethyl acetate, ethanol and toluene. The original catalyst (K-OMS-2) presented high catalytic activity for ethyl acetate and ethanol oxidation, achieving 90% conversion into CO(2) around 200 degrees C for both pollutants. Toluene was much harder to oxidize, requiring a temperature near 270 degrees C for the same conversion. The original catalyst was mechanically treated in a ball mill at different intensities, in order to decrease the particle size for subsequent impregnation onto structured supports, as small particle sizes are usually recommended. The catalytic activity of the materials decreases with the increase in the severity of this treatment, which is related to the decrease of the surface area of the catalysts, since the other properties (phase purity, thermal stability, surface oxygen, average oxidation state and reactivity of the oxygen species) are similar among the catalysts with different ball milling treatments. For comparison, a platinum-based catalyst (1%-Pt/Al(2)O(3)) was also tested, which exhibited a high activity for toluene, but much lower activities for the two other volatile organic compounds tested. A long-term experiment, using ethanol as model pollutant, showed that the cryptomelane catalyst was stable for more than 100 h" |
Keywords: | Catalysis Oxidation-Reduction Platinum Toluene *Volatile Organic Compounds Manganese oxides cryptomelane low-temperature catalytic oxidation volatile organic compounds; |
Notes: | "MedlineSantos, Diogo F M Soares, Olivia S G P Figueiredo, Jose L Pereira, Manuel Fernando R eng England 2018/06/21 Environ Technol. 2020 Jan; 41(1):117-130. doi: 10.1080/09593330.2018.1491639. Epub 2018 Jul 10" |