环氧丙烷在Li_3PO_4(001)表面吸附的密度泛函(DFT)研究

Density Functional Theory(DFT) Study on Adsorption of Propylene Oxide on Li_3PO_4(001) Surface

磷酸锂是催化环氧丙烷(PO)异构化制备烯丙醇的一种高效催化剂,因产率高、无三废、工艺简单等优点成为工业生产烯丙醇的主要催化剂。采用基于密度泛函(DFT)的广义梯度近似方法(GGA-PBE)研究环氧丙烷在Li_3PO_4(001)表面的吸附,发现环氧丙烷在Li_3PO_4(001)表面稳定吸附时,环氧丙烷上O原子与Li_3PO_4(001)表面Li^+相互作用,甲基H与Li_3PO_4(001)表面P-O-相互作用,进而提出了磷酸锂Lewis酸位Li^+和Brnsted碱位点P-O-共同作用催化环氧丙烷异构化形成烯丙醇的机理。

Lithium phosphate is an efficient catalyst for the isomerization of propylene oxide to prepare allyl alcohol.Due to its high yield,no waste and simple process,it has become the main catalyst used in industrial production of allyl alcohol. The adsorption of propylene oxide on the surface of Li3PO4（001） was investigated by the generalized gradient approximation（GGA-PBE） based on density functional theory（DFT）. When propylene oxide was adsorbed on the surface of Li3PO4（001）,the O atom and the methyl group H interacted with Li-＋ and P-O-on the surface of Li3PO4（001）,respectively. Through a series of analyzes,the mechanism of isomerization of propylene oxide to allyl alcohol by the synergistic interaction of lithium phosphate Lewis acid sites Li＋ and Brnsted base sites P-O- was presented.