Hydrodesulfurization activity results

It is interesting to note that Reddy and Manohar could show that M0S2 did also spread on the surface of AI2O3 supports. The resulting material developed a thiophene hydrodesulfurization activity which was identical to that measured on a conventionally impregnated and sulfided catalyst. 

Data from tests at 250,275,300, and 325 C were used to calculate pseudo-first order rate constants for the formation of H2S. These data are expressed on a standard Arriienius plot (Fig. 2) for which the linear least squares coefficient of determination, r, is 0.98. The apparent activation energy calculated from the slope is 28.5 kcal/mol. This result is in excellent agreement with the recent work of Abotsi, who studied the performance of carbon-supported hydrodesulfurization catalysts (10). Using Ambersorb XE-348 carbon lo ed with sulfided ammonium molybdate (3% Mo loading) prepared by the same procedure reported here, Abotsi hydrotreated a coal-derived recycle solvent The apparent activation energy for... 

Fortunately, the continued developments of the hydrodesulfurization process over the last two decades has resulted in the production of catalysts that can tolerate substantial amounts of nitrogen compounds, oxygen compounds, and metals without serious losses in catalyst activity or in catalyst life (Chapter 5). Thus, it is possible to use the hydrodesulfurization process not only as a means of producing low-sulfur liquid products but also as a means of producing low-sulfur, low-nitrogen, low-oxygen, and low-metals streams that can be employed as feedstocks for processes where catalyst sensitivity is one of the process features. 

Results suggest that interaction of the hydrogen sulfide and the platinum on the HZSM-5 is not very strong, therefore, the metallic nature of platinum is easily regenerated by the hydrogen during hydrodesulfurization. By this reason, Pt/HZSM-5 catalyst shows high and stable activity for the hydrodesulfurization of thiophene. 

The catalyst which has a larger pore diameter tends to show a lower deactivation rate, as well as lower HDS activity. Figure 1 shows one example of the results of residual hydrodesulfurization experiments testing three kinds of catalysts which have different pore diameters. The micro-reactors were operated under the same conditions, as shown in Figure 1. Catalyst A, Catalyst B and Catalyst C were the test catalysts which have the same properties with different pore diameters ( C > B > A). The activity and deactivation rate of each catalyst were shown to depend strongly on pore diameter, as shown in Figure 1. 

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