Pd-Ni/Al_(2)O_(3)催化剂上α-呋喃甲酸加氢反应研究

Study on the Performance of α-Furan Formic Acid Hydrogenation over Pd-Ni/Al_(2)O_(3) Catalysts under Mild Conditions

采用连续流动固定床微型反应器考察了Pd-Ni/Al2O3催化剂上α-呋喃甲酸加氢生成α-四氢呋喃甲酸的反应.研究了反应的温度,压力,气、液体流速,以及氢油比对催化反应性能的影响.结果表明:在2.5MPa,200 ℃,氢气空速6600h-1,液体空速3.0h-1,氢油比为200时,α-呋喃甲酸转化率为94%,α-四氢呋喃甲酸选择性100%,产率94%,催化剂连续运转300h后未见活性下降.应用程序升温还原(TPR)和程序升温脱附(TPD)技术考察了催化剂表面吸附状态与催化加氢活性的关系.结果表明Pd-Ni/Al2O3催化剂表面存在两种活性中心,催化加氢反应主要在较弱的活性中心上进行.该催化剂体系反应活性高,选择性和稳定性好,反应条件温和,操作简单,产物易分离,具有良好的应用前景.

The performance of α-furan formic acid hydrogenation over Pd-Ni/Al_2O_3 catalyst was investigated in fixed bed micro-reactor under different conditions such as reaction temperature, pressure, H_2 space velocity, space velocity of α-furan formic acid and solvent, ratio of H_2 and α-furan formic acid and so on. The results obtained showed that the conversion of α-furan formic acid was up to 94%, while the selectivity toward α-tetra-hydro-furan formic acid dramatically reached 100%, consequently, the yield of α-tetra-hydro-furan formic acid was 94%. The catalysts were characterized by means of temperature-programmed reduction(TPR), temperature-programmed desorption of H_2 (H_2-TPD) to study the relationship between the catalytic activity of Pd-Ni/Al_2O_3 catalyst and adsorption of H_2.The results showed that there were two kinds of active sites on Pd-Ni/Al_2O_3 catalyst. catalytic hydrogenation underwent reactions mainly on the weeker active sites on Pd-Ni/Al_2O_3 catalyst.The duration test showed that no sign of deactivation in α-funan formic acid hydrogenation observed over the period of more than 300 hour. The catalysts and catalytic process with high activity and selectivity, high stability, facile separation of catalyst from products, and mild process conditions would open interesting and perspectives for hydrogenation of α-furan formic acid both for research and for applications.