High performance Pd/beta catalyst for the production of gasoline-range iso-paraffins via a modified Fischer-Tropsch reaction

The direct synthesis of gasoline-range iso-paraffins from synthesis gas (CO + H-2, syngas) via a modified Fischer-Tropsch (FT) reaction was intensively studied under a wide range of reaction conditions by the combination Of CO/SiO2 and Pd/beta in a consecutive dual reactor system. Results indicate that high selectivity of gasoline-range iso-paraffins (iso-paraffins relative to C-4+ hydrocarbons was about 80%) could be achieved with the presence of Pd/beta catalyst in the lower reactor. Moreover, the performance of the Pd/beta catalyst for the titled reaction and the product composition can be significantly regulated by independently changing the reaction conditions such as catalyst amount, reaction temperature, and hydrogen partial pressure in the lower reactor. It was found that the Pd/beta catalyst used in this work was very active and stable even at a reaction temperature as low as 503 K. With the increase of hydrogen partial pressure in the lower reactor, the long-term stability of the Pd/beta catalyst was significantly enhanced. (c) 2005 Elsevier B.V. All rights reserved.