Treatment of nitrate-polluted natural waters by reduction in catalytic membrane contact reactors
A catalytic membrane reactor in contactor or interfacial configuration (CCMR) has been developed for NO3 reduction in mineral waters with different salt content. The catalytic layer of the membrane was formed by a PdCu catalyst supported on carbon black. The reagent-catalyst contact model of this re...
| Autores: | , , , |
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| Tipo de documento: | artigo |
| Data de publicação: | 2024 |
| País: | España |
| Recursos: | Universidad Autónoma de Madrid |
| Repositório: | Biblos-e Archivo. Repositorio Institucional de la UAM |
| Idioma: | inglês |
| OAI Identifier: | oai:repositorio.uam.es:10486/716077 |
| Acesso em linha: | http://hdl.handle.net/10486/716077 https://dx.doi.org/10.1016/j.seppur.2024.130261 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Catalytic Membranes Contactor Configuration H2 Mass Transfer Mineral Water NO3 Reduction Pd-Cu Catalysts Química |
| Resumo: | A catalytic membrane reactor in contactor or interfacial configuration (CCMR) has been developed for NO3 reduction in mineral waters with different salt content. The catalytic layer of the membrane was formed by a PdCu catalyst supported on carbon black. The reagent-catalyst contact model of this reaction system offers an excellent control of H2 availability at the active sites, allowing for NO3 reduction with very low NH4+ production. At optimal conditions in weakly mineralized water matrix, NH4+ selectivity values lower than 2 % were reached at NO3 conversions of around 80 %. In addition to this, treatment conditions leading to compliance with standards for drinking water were achieved for water polluted with 100 mg/L of NO3. The effect of salt type and concentration in NO3 conversion and NH4+ selectivity was assessed, with HCO3, Cl and SO4 2- being the main ions contributing to the loss of activity, probably due to competitive adsorption on the active sites and promoting NH4+ formation. The partial pressure of H2 in the reactor gas feed showed a clear impact on catalytic activity and NH4+ selectivity, enabling for modulation of the catalytic performance |
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