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Materiales mesoporosos tipo hidrotalcita obtenidos por sol-gel asistido con irradiación de microondas y su evaluación catalítica y absorbente

 

Hydrotalcite-like mesoporous materials obtained by the sol-gel method with microwave radiation and his evaluation as catalists and sorbent

 

E. Ramos-Ramírez¹*, N.L. Gutiérrez-Ortega², G. del Angel-Montes³, F. Tzompantzi-Morales³, F. Acevedo-Aguilar¹ y L.E. Mendoza-Puga²

 

¹ Depto. de Química, Universidad de Guanajuato, Noria Alta s/n Guanajuato, Gto., C.P. 36050, éxico. * Corresponding author. E-mail: ramosre@ugto.mx Tel. (52) 473-73-2-00-06 ext. 6005, Fax. Ext. 6001.

² Depto. de Ingeniería Civil, Universidad de Guanajuato, Juárez 77, Zona Centro, Guanajuato, Gto., C.P. 36000, México.

³ Depto. de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco No.186, México D.F. C.P.09340, México.

 

Received April 8, 2015;
Accepted July 14, 2015.

 

Resumen

Con la finalidad de obtener materiales potencialmente útiles en la optimización de procesos catalíticos industriales y en remediación ambiental para la eliminación de desechos tóxicos, en este trabajo se presenta la síntesis de Materiales Mesoporosos Tipo Hidrotalcita por el método sol-gel asistido con irradiación de microondas a partir de alcóxidos metálicos de magnesio y aluminio con relaciones Mg/Al de 2 y 3. Los materiales obtenidos fueron caracterizados fisicoquímicamente para la determinación de sus propiedades estructurales, texturales y térmicas. Para la evaluación de la actividad catalítica y adsorbente de los materiales, se probó la reacción de descomposición de 2-propanol, y la remoción de cromo (VI) de soluciones acuosas. Los catalizadores obtenidos después del tratamiento térmico de los Materiales Mesoporosos Tipo Hidrotalcita a 400°C resultaron ser activos para la descomposición del 2-propanol dando una mayor selectividad a propeno que a acetona, con lo cual se confirma que los sólidos son preferentemente ácidos; además los Materiales Mesoporosos Tipo Hidrotalcita mostraron una buena capacidad de remoción de cromatos de soluciones acuosas con valores de 44 y 45mg de cromo (VI)/g de Material Mesoporos Tipo Hidrotalcita, mostrando el potencial que tienen dichos materiales para su empleo en procesos de remediación ambiental.

Palabras clave: materiales mesoporosos tipo hidrotalcita, método sol-gel, irradiación de microondas, hidrotalcitas ácidas, cromo (VI).

 

Abstract

With the purpose of obtaining materials potentially useful in the optimization of catalytic industrial processes and in environmental remediation for the elimination of toxic waste, this work presents the synthesis of hydrotalcite like mesoporous materials by the sol-gel method with microwave irradiation from metallic alcoxides of magnesium and aluminium with relations Mg/Al of 2 and 3. The materials obtained were characterized for the determination of their structural, thermal and textural properties. For the evaluation of the catalytic and adsorption capacities of the materials, these were probed both in the reaction of 2-propanol decomposition, as well as in the removal of chrome (VI) from watery solutions; the above mentioned evaluation shows the potential that they have for their employment in processes of environmental remediation. The catalysts obtained on having thermal treated of hydrotalcite like mesoporous materials to 400°C turned out to be active for the decomposition of 2-propanol giving a greater selectivity to propylene that to propanone, with which the formation of preferably acidic compounds is confirmed. In addition the hydrotalcite like mesoporous materials a showed a good capacity for the removal of chromates from watery solutions with values of 44 and 45mg of chrome the (VI)/g of hydrotalcite like mesoporous materials.

Keywords: hydrotalcite like mesoporous materials, sol-gel method, microwave irradiation, acid hydrotalcite chromium (VI).

 

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