Improvements to the Cu-and Fe-Based Catalysts

Despite the extensive list of potential drawbacks with existing commercial catalysts, few new WGS catalyst formulations have been commercialized in the past decades. Based on the data compiled by Armor,20,21 no new WGS catalysts were commercialized during the 1980s, while only two new catalysts were developed during the 1990s by the Siid-Chemie Group a ferrochrome catalyst promoted with Cu was developed for enhanced activity with suppressed Fischer-Tropsch by-product 

Also notable in the direction of classical catalyst improvement is the research conducted by Rhodes et al.22 A series of coprecipitated promoters were evaluated on ferrochrome catalyst activity at temperatures between 350 and 440 °C. It was found that activity decreases in the following order Hg Ag Ba Cu Pb unpromoted B. A noticeable compensation effect observed in the correlation between preexponential factors and apparent activation energies led the authors to conclude that these promoters might only influence the CO adsorption on catalyst rather than the course of surface reactions. 

In a recent patent issued to Siid-Chemie,23 an improvement to the CuZn-Al203 catalyst is described in which substitution of about 20% of the total Al with a (Cu,Zn)-hydrotalcite precursor containing a similar amount of aluminum improved both Cu dispersion and its activity. 

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