Catalytic ozonation of naphthenic acids in the presence of carbon-based metal-free catalysts: Performance and kinetic study
| Autor: | Selamawit Ashagre Messele, Pamela Chelme-Ayala, Mohamed Gamal El-Din |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Ozone
Radical chemistry.chemical_element 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis 0104 chemical sciences chemistry.chemical_compound Reaction rate constant Adsorption chemistry Naphthenic acid Degradation (geology) 0210 nano-technology Carbon Nuclear chemistry |
| Zdroj: | Catalysis Today. 361:102-108 |
| ISSN: | 0920-5861 |
| Popis: | This study examined the use of carbon-based metal-free materials as catalysts for the catalytic ozonation of a model naphthenic acid (NA) compound (1,3-Adamantanedicarboxylic acid; ADA). Adsorption, single ozonation and catalytic ozonation experiments were performed using ADA concentration of 50 mg/L, 0.5 g/L of carbon materials, and 30 mg/L of applied ozone (O3) dose, at pH 8. The results showed that, after 15 min of reaction, less than 5 % of ADA was removed by adsorption, while 33 % of ADA was removed by single ozonation. For the catalytic ozonation study, among the materials tested, the best performance was obtained using carbon xerogels prepared at pH 5.5 (CX5.5), reaching 65 % of ADA removal after 15 min of reaction. The first-order rate constant of O3 + CX5.5 (0.0631 min−1) was almost two times higher than that of single ozonation (0.0258 min−1). Hydroxyl radicals were the main responsible species for the ADA degradation. In general, the results confirmed that catalytic ozonation process is an efficient and promising approach for environmental applications. |
| Databáze: | OpenAIRE |
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