(544az) The Effect of Inert Pellet Size in the Fixed-Bed Reactor for Fischer-Tropsch Synthesis

Lately the fluctuation of high energy cost has motivated researchers to investigate alternative technologies with higher efficiencies. The Fischer-Tropsch Synthesis (FTS) process is considered as one of the promising alternative technologies for the clean energy production. In the FTS process conversion of synthesis gas to hydrocarbon products occurs and it takes the highly released heat from the exothermic reaction by synthesis of hydrocarbons. This exothermic reaction causes elevated temperature at the inlet of the fixed bed reactor and consequently undesirable byproducts such as methane and light hydrocarbon are mainly produced. It is a critical loss in the point of an economical operation.

In this study, in order to overcome the above mentioned problem, Ru/Co/Al₂O₃ catalysts for FTS reaction were prepared via impregnation method, and the catalytic evaluation tests were carried out in the fixed-bed reactor to investigate the effect of inert pellets in catalytic bed. The experiment was carried out using different size of inert materials (γ-Al₂O₃) including 1, 1.8 and 2.5 mm.

The catalytic performance was studied by conversion of CO, selectivity of CH₄ and C₅+ under the same GHSV. Furthermore the effect of different type of inert material pellet in FTS fixed bed reactor were discussed. It was found that various size of inert material has exhibited different contact area with catalyst and inert material which it led to different heat transfer coefficients. It was also observed that this phenomena influences the releasing heat that has been generated from the exothermic reaction over the catalyst.