摘要
本文报道了用回流法制备体相的和KIT-6稀释的青铜型W-Nb-O混合氧化物.研究了铌和介孔硅胶的掺入对催化剂物化性质的影响. Nb的加入有利于形成单相青铜结构氧化物,并改善了Lewis酸性;而KIT-6的加入使混合金属氧化物颗粒在稀释剂上分散得很好.这些稀释的W-Nb-O催化剂的比表面积和中孔体积增加.通过C-C键形成反应,对材料进行了模型混合水溶液(丙酮/丙醛/乙醇/乙酸/水重量比为5/25/10/30/30)的定值化试验.表面Lewis酸性的增加是反应过程中总有机产率达最大的关键(C5-C10产物).最好的催化剂在连续使用五次后仍保持其催化性能.
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.
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~~
