کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1262320 971858 2008 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Synthesis of Ln-doped MCM-41 mesoporous materials and their catalytic performance in oxidation of styrene
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Synthesis of Ln-doped MCM-41 mesoporous materials and their catalytic performance in oxidation of styrene
چکیده انگلیسی

Using cetyl-trimethyl-ammonium bromide (CTMAB) as the template agent and tetraethylorthosilicate (TEOS) as the silica source, the MCM-41 mesoporous materials were synthesized with La or Ce incorporated in the framework under hydrothermal conditions. The structure and the state of La or Ce were investigated through the analyses of XRD, nitrogen adsorption-desorption, FT-IR, and UV-Vis. XRD and N2 adsorption-desorption results showed that Ln-MCM-41 exhibited the loss of the lattice ordering of the MCM-41 construct, and larger unit cell parameter and pore diameter than pure silica MCM-41. The FT-IR and UV-Vis results indicated the presence of isolated terra-coordinated La or Ce ions in the framework and other Ln species dispersed highly on the Ln-MCM-41 surface simultaneously. Furthermore, their catalytic behaviors in the oxidation of styrene were studied using H2O2 as the oxidant. The La-MCM-41 catalysts exhibited high reactivity and the reactivity increased with the increase of the La content in the La-MCM-41 samples. On the contrary, Ce-MCM-41 catalysts showed low reactivity in the oxidation of styrene and the conversion of styrene decreased with the increase of the Ce content in the Ce-MCM-41 samples.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Rare Earths - Volume 26, Issue 1, February 2008, Pages 59-65