Uronic Hydrogen Off The The Carbonyl Furan Catalytic Reaction

Furan is a compound of industrial interests because of its use as organic intermediate, solvent and for manufacture of polymers. Furan was manufactured traditionally by three processes:decarboxylation of furoic acid, oxidation of furfural and oxidation of butadiene. But the first two processes consume energy largely and the catalysts they used pollute the environment badly and easily lose their catalytic activity. The butadiene oxidation method has the limitation of low activity. Decarbonylation of furfural overcomes such limitations and becomes widely used and studied nowadays.Process conditions of decarbonylation of furfural on a fixed-bed continual reactor were systematically studied in this thesis. The catalyst used was Pt-K/Al203-Ti02. On the basis of the experiment results, the best process conditions were obtained. They are as follows: catalyst loading volume:6ml; particle size:40-60mesh; temperature:300; pressure:0.3MPa; LHSVrlh-1; H2/furfural (molar ratio) :2. The conversion of furfural was 98. 89% and the yield of furan was nearly 50% at the above conditions. The yield of main by-product, 2-methylfuran was 15%.The results of the experiment showed that in the decarbonylation reaction of furfural, the conversion of furfural changed differently in the course of the reaction at different conditions [temprature, pressure, H2/furfural (molar, ratio), or space velocity]. But the overall trend of the conversion of furfural dropped slowly with the reaction going on. The selectivity of furan increased in the course of the reaction. Resinification of furfural on the catalyst was the main cause of deactivation.Catalytic activity of the following catalysts:K-Mo-Co/Si02, Pd-K-Mo-Co/Si02, HP+Pd-K-Mo-Co/Si02(l:l) and Pd-K/Al203-Ti02(more TiO2) were studied. Not onlytheir reaction activities were low but also they were easy to lose activity. Also many deep hydrogenation products were found on some of the catalysts. So the activities of such catalysts were inferior to that of catalyst Pt-K/Al203-Ti02.