摘要
Abstract
The catalytic transfer hydrogenation of cinnamaldehyde to cinnamyl alcohol is of great practical significance,and the catalyst is the key to achieving selective hydrogenation of cinnamaldehyde.A series of ZrO(OH)2 catalysts were prepared by precipitation method at different aging temperatures,and ZrO2-25 was obtained by calcining ZrO(OH)2-25,which was aged at 25℃.The crystal phase structures,textural properties,microscopic morphologies,acid sites and—OH contents of ZrO(OH)2-25 and ZrO2-25 were characterized by XRD,N2 adsorption/desorption,SEM,Py-IR and XPS,respectively.The catalytic performances of the two catalysts were evaluated,and the effects of aging temperatures,reaction temperatures,cinnamaldehyde feeding amounts and hydrogen donor types on the catalytic performance of ZrO(OH)2-25 were investigated.The results show that ZrO(OH)2-25 exhibits amorphous state with specific surface area of 295 m2/g,while ZrO2-25 has tetragonal crystal structure with specific surface area of 144 m2/g.Under the optimal reaction conditions of 0.25 mmol cinnamaldehyde,3 mL isopropanol as hydrogen donor,40 mg ZrO(OH)2-25,1 MPa N2,700 r/min reaction temperature of 120℃and reaction time of 4.0 h,the cinnamaldehyde conversion rate reaches 97.1%and the cinnamyl alcohol selectivity reaches 82.4%.The better catalytic performance of ZrO(OH)2-25 than ZrO2-25 under the same conditions is attributed to abundant—OH on its surface.关键词
肉桂醛/催化转移加氢/肉桂醇/ZrO(OH)2Key words
cinnamaldehyde/catalytic transfer hydrogenation/cinnamyl alcohol/ZrO(OH)2分类
化学化工
