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Apagar la hidrogenación del peróxido de hidrógeno en el proceso de síntesis directa
Jennifer K Edwards1, Benjamin Solsona, Edwin Ntainjua N
1School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
Science (New York, N.Y.)
|February 21, 2009
Resumen
Los investigadores desarrollaron un nuevo método para sintetizar peróxido de hidrógeno (H2O2) directamente a partir de hidrógeno y oxígeno. Los catalizadores de oro-palladio tratados con ácido evitan la descomposición de H2O2, logrando altos rendimientos y selectividad.
Área de la Ciencia:
- La catálisis de la catálisis.
- Ciencia de los materiales Ciencia de los materiales.
- Ingeniería Química Ingeniería Química.
Sus antecedentes:
- El peróxido de hidrógeno (H2O2) es un químico industrial vital utilizado como desinfectante y agente blanqueador.
- La producción actual de H2O2 se basa en un proceso indirecto de antraquinona.
- La síntesis directa de H2O2 a partir de H2 y O2 es deseable, pero se ve obstaculizada por la descomposición mediada por catalizadores.
Objetivo del estudio:
- Desarrollar un catalizador que permita una síntesis directa eficiente de peróxido de hidrógeno.
- Para superar el desafío de la descomposición de H2O2 durante la síntesis directa.
- Mejorar la selectividad y el rendimiento de la producción de H2O2.
Principales métodos:
- Utilizó nanopartículas de aleación de oro y paladio soportadas en carbono.
- Se aplicó un pretratamiento ácido al soporte de carbono.
- Investigó el efecto del pretratamiento en la estructura del catalizador y el rendimiento de la síntesis de H2O2.
Principales resultados:
- El pretratamiento con ácido desactivó efectivamente la vía de descomposición de H2O2.
- El tratamiento dio como resultado nanopartículas de aleación más pequeñas, que probablemente inhiben los sitios de descomposición.
- Los catalizadores pretratados con ácido lograron altos rendimientos de H2O2 con una selectividad de más del 95%.
Conclusiones:
- El pretratamiento ácido de soportes de carbono es una estrategia viable para crear catalizadores estables para la síntesis directa de H2O2.
- Este método ofrece una ruta prometedora para una producción de H2O2 más eficiente y selectiva.
- Los hallazgos allanan el camino para mejorar los procesos industriales para la fabricación de peróxido de hidrógeno.
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