The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO H2) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H2 ratio synthesis gases derived from modern coal gasifiers. This is because in addition to reasonable F-T activity, the F-T catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray drying and will be scalable using commercially available equipment. The research will employ among other measurements, attrition testing and F-T synthesis, including long duration slurry reactor runs in order to ascertain the degree of success of the various preparations. The goal is to develop an Fe catalyst which can be used in a SBCR having only an internal filter for separation of the catalyst from the liquid product, without sacrificing F-T activity and selectivity. Two doubly promoted iron catalysts of standard Ruhrchemie composition were prepared by coprecipitation followed by spray drying (atomization). These catalysts had a particle size of 20 to 40 ?m. One catalyst had no silica (HPR-23) while the other had a significant amount of silica (HPR-22). The catalyst with no silica (HPR-23) had much higher activity and selectivity. It gave 95% CO conversion at 1.48 MPa, H2/CO=0.67, and 2 nL/(g of cat-h). Also, the selectivity to C2 hydrocarbon was 95% and the " was around 0.9. The attrition resistance of HPR-23 was also significantly better than HPR-22. It appears that silica is detrimental to performance of a spray dried iron catalyst.