Abstract:Highly dispersed Ru-PEGx/NaY catalyst was prepared by impregnation-precipitation method using PEG(400) as the dispersant and (NH4)2CO3 as the precipitant. The samples were characterized by XRD, TEM, H2-TPR, ICP-AES and XPS. The results showed that the suitable PEG(7.5 mL) could trap the Ru3+ ions, and then increased the repulsion among Ru3+ ions, thereby impeding the agglomeration of Ru particles. The catalytic performance of the different samples was evaluated via p-nitrotoluene (PNT) liquid-phase hydrogenation to p-methyl-cyclohexylamine (PMC) reaction, with the PNT conversion and PMC selectivity as indicator. The results indicated that the catalytic performance of Ru-PEG7.5/NaY was the most excellent, the PNT conversion and the selectivity of PMC were found to be as high as 100 % and 95.0 % under the optimum conditions which the amount of Ru-PEGx/NaY catalyst was 0.50 g, reaction time was 35 min, the pressure of H2 was 3.5 MPa, the reaction temperature was 160 ℃, the amount of PNT was 5.00 g, stirring rate was 900 r/min and isopropyl alcohol was 300 mL. In addition, It was found that the activity of Ru-PEG7.5/NaY changed almost nothing after the fifth run, indicating the Ru-PEG7.5/NaY catalyst has good stability.