| 초록 |
Cyclotrimerization of acetylene to benzene was investigated on Pd/titania as a means to utilize acetylene as the feedstock for synthesis of valuable hydrocarbons. Our research focused the effect of Pd loading, additional metal oxide, and reduction treatment upon the catalytic behavior of Pd/titania for the reaction in the laboratory scale. Pd/titania was prepared by the incipient wetness technique using palladium nitrate solution and titania powder, and was characterized by XRD and TEM to analyze the distribution of crystallographic plane and particle size, and by CO chemisorption to analyze the degree of dispersion of Pd crystallites. Prepared catalyst was subjected to pre-treatment consisting of calcinationat 400℃ followed by reduction at 400℃ to 600℃ in a packed bed reactor. Flow of acetylene diluted by argon was then reacted at 80℃ to 110℃, and acetylene conversion, benzene selectivity, and catalyst stability were measured by gas chromatography and mass spectrometry. Hydrocarbons accumulated on the deactivated catalyst were analysed by mass spectrometry, with temperature ramping in flow of hydrogen diluted by argon. As the composition of 20ml/min acetylene/argon flow was varied for 0.3 gram of 5wt% Pd/titania, benzene selectivity and catalyst stability favored low partial pressure of acetylene. |
