期刊论文
Zhang, Li
Song, CS; Zhou, JX (reprint author), Dalian Univ, Coll Environm & Chem Engn, Dalian 116622, Peoples R China.
Mao, Jingbo,Li, Shenmin,Yin, Jingmei,Sun, Xudong,Guo, Xinwen,Song, Chunshan,Zhou, Jinxia
2018-09-15
APPLIED CATALYSIS B-ENVIRONMENTAL
SCIE、EI
J
232
1-10
0926-3373
Levulinic acid; gamma-Valerolactone; CuAg/Al2O3 catalyst; Metal leaching; In situ reduction
Metal leaching is a major issue in efficient production of gamma-valerolactone (GVL) from levulinic acid (LA) under mild reaction conditions. In this study, Ag was added to Cu-supported gamma-Al2O3 catalyst to suppress Cu leaching in the hydrogenation of LA into GVL. The CuAg/Al2O3 catalyst was reduced in situ during the reaction, and Cu leaching in the solution was significantly suppressed. The bimetallic catalyst without reduction pretreatment achieved approximately 100% yield to GVL and exhibited good reusability in nine consecutive cycles under mild reaction conditions of 180 degrees C and 1.4 MPa H-2 pressure in tetrahydrofuran (THF). The strong interplay in the geometric and electronic effects between Cu and Ag was verified through XPS, H-2-TPR, TEM, STEM/EDS, and XRD analyses. This paper extensively discussed the mechanism of Ag on preventing Cu leaching and the superiority of in situ reduction in solution over external reduction in gas.