钌取代的磷钼钒多金属氧酸盐在γ-戊内酯制备中的性能研究  

Investigation of RuPMoV Polyoxometalates in Preparation ofγ-Valerolactone

作　　者：邵雪婷 孙钟 时君友[1] 段喜鑫[1] SHAO Xueting;SUN Zhong;SHI Junyou;DUAN Xixin(Collegeof Materials Science and Engineering,BeiHua University,Jilin 132013,China;College of Chemical Engineering,Northeast Electric Power University,Jilin 132012,China)

机构地区：[1]北华大学材料科学与工程学院,吉林吉林132013 [2]东北电力大学化学工程学院,吉林吉林132012

出　　处：《林产化学与工业》2021年第2期65-72,共8页Chemistry and Industry of Forest Products

基　　金：国家自然科学基金资助项目(31971616,31901263)。

摘　　要：首先合成了不同氧化性的磷钼钒多金属氧酸盐(HPMoV)——H_(4)PMo_(11)VO_(40)(V1)、H_(5)PMo_(10)V_(2)O_(40)(V2)和H_(6)PMo_(9)V_(3)O_(40)(V3),再通过Ru^(3+)与HPMoV复合引入Lewis酸位点,制备同时具有酸性和强氧化性的RuPMoV系列催化剂——Ru_(4/3)PMo_(11)VO_(40)(4-V1)、Ru_(5/3)PMo_(10)V_(2)O_(40)(5-V2)和Ru2PMo9V3O40(6-V3),并通过XRD、FT-IR、SEM、XPS和NH3-TPD等方法对催化剂结构进行表征;以甲酸(FA)作为氢源,在FA/H2O体系中,乙酰丙酸(LA)为原料催化转化制备γ-戊内酯(GVL),比较了不同催化剂的催化性能,考察了反应条件对催化性能的影响,并分析了反应的动力学。结构表征结果表明:Ru^(3+)已经成功引入多金属氧酸盐结构中,Ru^(3+)对HPMoV中H+的置换并没有改变多酸阴离子的结构,RuPMoV系列催化剂同时具有较强的酸性和氧化性。催化活性研究结果表明:催化剂5-V2的GVL选择性最高,5-V2用量0.1 g,FA用量6 mmol,LA 2.5 mmol,H_(2)O 5 mL,反应温度160℃条件下反应8 h时,LA转化率为98.1%,GVL产率为97.1%,GVL选择性为99.0%;该催化剂使用5次后GVL产率仍可达到87.5%,具有较好的重复使用性能;反应动力学分析表明该反应为一级反应,活化能为49.59 kJ/mol,指前因子为2.89×10^(5)。A series of polyoxometalates(HPMoV)catalysts,H_(4)PMo_(11)VO_(40)(V1),H_(5)PMo_(10)V_(2)O_(40)(V2)and H_(6)PMo_(9)V_(3)O_(40)(V3),with different oxidizability were synthesized.Then Ru^(3+)was combined with HPMoV as Lewis acid cites.As a result,RuPMoV catalysts including Ru_(4/3)PMo_(11)VO_(40)(4-V1),Ru_(5/3)PMo_(10)V_(2)O_(40)(5-V2)and Ru2PMo9V3O40(6-V3)were prepared,which had both acidity and strong oxidizability.XRD,FT-IR,SEM,XPS and NH3-TPD were used to characterize the structure of the catalysts.The catalytic performance,reaction factors and kinetics were investigated during the reaction of converting levulinic acid(LA)intoγ-valerolactone(GVL)in formic acid/water(FA/H2O)system,where FA was performed as hydrogen source.The results indicated that Ru^(3+)was introduced into the frame of polyoxometalates and the replacement of H+in HPMoV by Ru^(3+),which did not change the structure of polyacid anions.The RuPMoV catalysts had the strong acidity and oxidizability.5-V2 had the highest catalytic performance;at the condition of 0.1 g 5-V2,6 mmol FA,2.5 mmol LA,5 mL H_(2)O,160℃and 8 h,the LA conversion was 98.1%and the GVL yield and selectivity were 97.1%and 99.0%,respectively.The yield of GVL could be up to 87.5%when the 5-V2 catalyst was reused for 5 times.The reaction kinetics exhibited a first-order reaction with the activation energy of 49.59 kJ/mol and the pre-exponential factor of 2.89×10^(5).

关 键 词：多金属氧酸盐 乙酰丙酸 γ-戊内酯 钌 

分 类 号：TQ35[化学工程]