Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were a...Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were assessed on the photo-Fenton degradation of phenolic aqueous solutions by H2O2 using near ultraviolet irradiation (254 nm) at room temperature and initial neutral pH. Their catalytic performance was mentioned in terms of phenol and TOC (total organic carbon) conversions. Several complementary techniques, including X-ray, nitrogen sorption isotherms, UV (Ultraviolet) visible, were used to evaluate the final structural and textural properties of calcined Fe-SBA 15 materials. These materials show a high activity and stability of iron species.展开更多
This work reports the preparation of bulk and KIT-6-diluted W-Nb-O mixed oxide bronzes by a reflux method. The influence of the incorporation of Nb and a mesoporous silica on the physicochemical features of the cataly...This work reports the preparation of bulk and KIT-6-diluted W-Nb-O mixed oxide bronzes by a reflux method. The influence of the incorporation of Nb and a mesoporous silica on the physicochemical features of the catalysts is studied. The addition of Nb favors the formation of single-phase oxide bronze structure, with improved Lewis acidity;while the incorporation of KIT-6 gives rise to well-dispersed mixed metal oxide particles on the diluter. These diluted W-Nb-O catalysts present enhanced surface areas and mesopore volumes. The materials have been tested in the valorization of an aqueous model mixture (acetol/propanal/ethanol/acetic acid/water weight ratio of 5/25/10/30/30), through C-C bond formation reactions. The increase in the Lewis nature of surface acid sites stands as the key point to maximize the total organic yield during the reaction (C5-C10 products). The best catalysts maintain their catalytic behavior after five consecutive uses.展开更多
文摘Iron-containing SBA-15 catalysts have been prepared following different synthesis routes, direct synthesis by adjusting pH at 3 and 6 and with post synthesis procedure. Activity and stability of these materials were assessed on the photo-Fenton degradation of phenolic aqueous solutions by H2O2 using near ultraviolet irradiation (254 nm) at room temperature and initial neutral pH. Their catalytic performance was mentioned in terms of phenol and TOC (total organic carbon) conversions. Several complementary techniques, including X-ray, nitrogen sorption isotherms, UV (Ultraviolet) visible, were used to evaluate the final structural and textural properties of calcined Fe-SBA 15 materials. These materials show a high activity and stability of iron species.
基金Financial support by the Spanish Government(RTI2018-099668-B-C21,PGC2018-097277-B-100,and SEV-2016-0683)the Severo Ochoa Excellence Program(SVP-2014-068669)the “La Caixa-Severo Ochoa” Foundation,respectively,for their fellowships~~
文摘This work reports the preparation of bulk and KIT-6-diluted W-Nb-O mixed oxide bronzes by a reflux method. The influence of the incorporation of Nb and a mesoporous silica on the physicochemical features of the catalysts is studied. The addition of Nb favors the formation of single-phase oxide bronze structure, with improved Lewis acidity;while the incorporation of KIT-6 gives rise to well-dispersed mixed metal oxide particles on the diluter. These diluted W-Nb-O catalysts present enhanced surface areas and mesopore volumes. The materials have been tested in the valorization of an aqueous model mixture (acetol/propanal/ethanol/acetic acid/water weight ratio of 5/25/10/30/30), through C-C bond formation reactions. The increase in the Lewis nature of surface acid sites stands as the key point to maximize the total organic yield during the reaction (C5-C10 products). The best catalysts maintain their catalytic behavior after five consecutive uses.