当前位置: X-MOL 学术J. Catal. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
High {0 0 1} faceted TiO2 nanoparticles for the valorization of oxygenated compounds present in aqueous biomass-derived feedstocks
Journal of Catalysis ( IF 7.3 ) Pub Date : 2018-01-04 , DOI: 10.1016/j.jcat.2017.12.018
A. Fernández-Arroyo , M.A. Lara , M.E. Domine , M.J. Sayagués , J.A. Navío , M.C. Hidalgo

{0 0 1} faceted TiO2 catalysts are hydrothermally synthesized by using titanium(IV) isopropoxide and butoxide precursors (ISO and BUT TiO2 samples) together with HF addition. Their activity and stability are evaluated in the catalytic condensation of light oxygenated organic compounds present in an aqueous model mixture simulating a real bio-refinery effluent, under moderate operation conditions. High {0 0 1} faceted TiO2 catalysts show organic products yields superior to those attained with other TiO2 samples (anatase, rutile, and P25). This enhanced catalytic activity relates to their physico-chemical and textural properties, such as high surface area (≈100 m2/g), regular morphology (platelets conformed by partially agglomerated TiO2 nanoparticles), and adequate Lewis acidity. XRD and Raman measurements evidence the unique presence of anatase crystalline phase in both ISO and BUT materials, in which the use of HF during synthesis produces the preferential growth of TiO2 crystals mainly exposing the {0 0 1} plane. This effective {0 0 1} facet exposition directly determines catalytic results. Moreover, TiO2 ISO catalyst shows outstanding stability under reaction conditions, maintaining practically unaltered their activity after several re-uses. In particular, Lewis acid sites present in TiO2 faceted materials are more stable in the presence of organic acids under aqueous environments. This opens new possibilities for the application of these materials in the valorization of light oxygenated compounds present in biomass-derived aqueous effluents.



中文翻译:

高{0 0 1}面状TiO 2纳米颗粒,用于水合生物质原料中存在的含氧化合物的增值

通过使用异丙醇钛(IV)和丁醇前体(ISO和BUT TiO 2样品)并加入HF,水热合成{0 0 1}刻面TiO 2催化剂。在温和的操作条件下,通过模拟实际生物精炼厂废水中水模型混合物中存在的轻氧化有机化合物的催化缩合,可以评估它们的活性和稳定性。高{0 0 1}面的TiO 2催化剂显示有机产品的产量优于其他TiO 2样品(锐钛矿,金红石和P25)。这种增强的催化活性与其物理化学和质地特性有关,例如高表面积(≈100m 2/ g),规则的形态(由部分团聚的TiO 2纳米颗粒组成的血小板)和足够的路易斯酸度。XRD和拉曼测量证明了在ISO和BUT材料中均存在锐钛矿晶相,其中在合成过程中使用HF可以优先生长主要暴露{0 0 1}平面的TiO 2晶体。这种有效的{0 0 1}小平面曝光直接决定了催化效果。此外,TiO 2 ISO催化剂在反应条件下显示出出色的稳定性,多次重复使用后实际上保持了其活性不变。特别地,TiO 2中存在路易斯酸位点在水性环境中存在有机酸时,多面材料更稳定。这为将这些材料应用到生物质衍生的废水中存在的轻氧化化合物的增值中提供了新的可能性。

更新日期:2018-01-04
down
wechat
bug