乙醛
巴豆醛
化学
氧气
无机化学
加合物
催化作用
乙醇
选择性
粒径
钙钛矿(结构)
分子
光化学
物理化学
有机化学
作者
Ren-Kai Chen,Tingfang Yu,Meng-Xun Wu,Tai-Wei Tzeng,Po‐Wen Chung,Yu‐Chuan Lin
标识
DOI:10.1021/acssuschemeng.8b02269
摘要
This study reports that the C2–C2 aldolization in ethanol conversion to C4 products, particularly butadiene, can be catalyzed by silica-supported LaMnO3 catalysts. The concentration and strength of Mn4+ was discovered to be related to the particle size of supported LaMnO3: the smaller the particle size is, the higher the concentration and acidity of Mn4+ are. The presence of high concentration and acidity of Mn4+ of small LaMnO3 particles concurrently increases the amount of weak basic nonstoichiometric oxygen, with which the surface concentration of Lewis acid–base adducts can be elevated. The Mn4+/nonstoichiometric oxygen pair is intrinsically active in C2–C2 aldolization, and the concentration of the paired site is positively correlated to the selectivity of C4 products. By coreacting ethanol with its evolved intermediates, that is, acetaldehyde and crotonaldehyde, we discovered the aldol condensation of acetaldehyde molecules to be rate-limiting. Accordingly, a plausible mechanism of aldolization of acetaldehyde molecules into C4 products mediated by the Mn4+/nonstoichiometric oxygen adduct of LaMnO3 was established.
科研通智能强力驱动
Strongly Powered by AbleSci AI