Comparative study of nano iron catalysts in the presence of the crude polymer matrix and their cross link polymer in the Fischer-Trophsch synthesis

Abstract

A new metal-polymer catalyst in a stable colloidal system, were prepared. Iron-paraffin catalysts, nano sized particles, with different polymers have been matrixes were used to examine the effects of polystyrene and their derivatives on chemical/structural properties through Fischer–Tropsch synthesis (FTS) and the yield as well. Nano size iron-containing particles distributed are suspended in the hydrocarbon medium of the slurry-reactor were found to have great impact and high percent conversion of CO to more than 70%. Polystyrene derivatives found to interact with Fe species by the formation of Fe3O4 oxide and amorphous hydrolyzed δ-FeOOH which were formed at the given conditions. All catalysts with a polymer found to have a bimodal distribution particle. In structural aspects, polystyrene derivatives increases the dispersion of Fe species and inhibits the coagulation of active iron particles, and on other hand, the chemical and structural effects would cause the increase of the FTS efficiency towered the selectivity of heavy hydrocarbons and olefins during the FTS. The state of iron and polymer-paraffin matrix were examined utilizing XRD and AFM techniques which showed the forms of ground state of iron as Fe3O4 oxide and amorphous hydrolyzed δ-FeOOH were exists. When the polystyrene derivatives are introduced, the proportion of amorphous paraffin found to be less than that in a crystalline state. The maximum conversion of CO (71%) and the yield of liquid hydrocarbons (63g.m-3) based on a cross-link polymer such as a polystyrene divinylbenzene (PS-DVB) used. A very interesting fact that the risen temperature found to have a small decrease in selectivity and an increase in conversion efficiency, this was observed in all reactions.