Novel Carbon Molecular Sieve Catalysts for Wax Suppression in the Fischer-Tropsch Reaction: Final Technical Report

摘要

The Type I and II IOM-CMS versions of the FT catalyst displayed both markedly improved on-stream behavior as well as a different product distribution than the untreated FT catalyst. Comparative results for IOM-CMS catalysts versus the untreated catalysts, indicate that they make predominantly lighter hydrocarbons and in reasonably high yields. (C1 to C4, >80%, approx.100 to 170 gm hydrocarbon/m sup 3 synthesis gas converted). In these catalysts the combined Fischer Tropsch/Hydrocracking (FT/HC) functionalities are in 1:1,3:1, and 6:1 (w/w) ratios, and are in the form of C-FT-HC TY-I, C-FT-HC Non-Sieving, and FT-HC (native). These systems were very well-behaved in the fixed bed mode, operation without clogging or sintering during the course of extended runs (>150 hrs). In summary, the IOM-CMS materials have been demonstrated with a wide variety of compositions and different adsorptive properties. Catalysts prepared with the IOM-CMS materials showed improved properties relative to the untreated Fischer-Tropsch catalysts. The formation of the carbon molecular sieving function did not deactivate the catalysts. In fact, the IOM-CMS forms of the catalysts were better behaved, displaying improved resistance to sintering and or clogging. Catalysts tested to-date showed high selectivities to the very short chain hydrocarbons, C1 to C4, but not to the gasoline fraction, C5 to C11. This may be due to the fact that the pore properties of the materials tested were in the 3A to 4A range. Shifting of this pore size to slightly higher values may produce a concomitant shift in the product distribution. 39 refs., 39 figs., 20 tabs. (ERA citation 12:040332)