Cutting oil-water emulsion wastewater treatment by microwave assisted catalytic wet peroxide oxidation
Cutting-oil in water emulsions (COWE) suppose an environmental threat due to their high volume, stability and low biodegradability (BOD5/COD: 0.07). So far, these effluents have been treated by physical methods which merely transfer the pollutants into another phase. In this work, Microwave-assisted...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Universidad Autónoma de Madrid |
| Repositorio: | Biblos-e Archivo. Repositorio Institucional de la UAM |
| Idioma: | inglés |
| OAI Identifier: | oai:repositorio.uam.es:10486/717801 |
| Acceso en línea: | http://hdl.handle.net/10486/717801 https://dx.doi.org/10.1016/j.seppur.2020.117940 |
| Access Level: | acceso abierto |
| Palabra clave: | AOP intensification graphite hot spot metal-free catalyst microwave wastewater treatment Química |
| Sumario: | Cutting-oil in water emulsions (COWE) suppose an environmental threat due to their high volume, stability and low biodegradability (BOD5/COD: 0.07). So far, these effluents have been treated by physical methods which merely transfer the pollutants into another phase. In this work, Microwave-assisted Catalytic Wet Peroxide Oxidation (MW-CWPO) is used for the first time in the degradation of COWE 0.5%w, using graphite as catalyst. Working at pH0: 9, graphite: 10 g/L, 15.7 g/L H2O2, at MW power of 800 W by pulsation method, complete demulsification and 82% Total Organic Carbon (TOC) removal is achieved in only 10 min. Furthermore, the remaining TOC in solution is mainly ascribed to malonic, acetic and formic acids, which results in readily biodegradable effluents (BOD5/COD: 0.93). The degradation mechanism is a complex combination of H2O2-mediated adsorption of the pollutants onto the graphite's surface and its subsequent oxidation mediated by hot-spots induced by MW radiation. This work also studies the influence of pH0, catalyst load and H2O2 dosage in COWE degradation. Finally, catalyst stability upon 3 consecutive cycles was tested and various techniques are proposed and examined for catalyst regeneration |
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