Modification Of Pd / C And Ru / C Noble Metal Catalyst Selected Allene Phosphate Hydrogenation Application

Phosphonomycin is a new broad antibacterial whose antimicrobial spectrum is much broad. In the industry manufacture, phosphonomycin is obtained through chemical synthesis. One step is preparing from 1, 2-proprnyl-phosphonic acid with palladium supported on activated carbon to cis-1-propenyl acid.Thermal or chemical pretreatments were prepared before the Ru metal impregnation to introduce oxygen groups. Pd/C catalysts promoted by Ru, Fe, Co, Ni catalysts were prepared to improve the catalytic activity. Ru/C catalysts with different loading amount were prepared. Ru/C catalysts promoted by several metal components were prepared. The catalytic activity of the catalysts were appraised by the selective hydrogenation of 1,2-proprnyl-phosphonic acid to cis-1-propenyl acid and the acetone hydrogenation respectively.The catalysts have been characterized by H₂-TPR, H₂-TPD, XRD, XPS and BET in order to obtain the relation between the surface characterization and the catalytic activity.The H2-TPR and H2-TPD results showed that the surface oxygen groups and the spillover hydrogen increased after nitric acid treatment. This facilitated the conversion from 1,2-proprnyl-phosphonic acid to cis-1-propenyl acid.When Pd/Ru=3/1, Pd-Ru/C catalyst had the maximal hydrogenation activity. The results showed that the Pd crystal is moderate and there is a big amount of hydrogen in a adsorption center.Pd/C catalysts promoted by Fe, Co had two low-temperature peaks (first peak:α active center, second peak :β active center) .The hydrogen adsorbed on the a active center decreased. The results showed that the first peak was assigned to the hydrogen adsorbed on the Ru and Pd. The second peak was attributed to the hydrogen adsorbed on the Ru metal. As the hydrogen adsorbed on a active center increased, the conversion from 1, 2-proprnyl-phosphonic acid to cis-1-propenyl acid increased, so did the the acetone hydrogenation.The results showed that Ru/C promoted by components in s section and f section improved the conversion of the selective hydrogenation reaction, while Ru/C promoted by the components in d section had the lower conversion. Ru/C promoted by Ba markedly improved the hydrogen adsorbed on a active center and the...