Influence of Phosphorus on Other Hydrotreating Catalysts

Influence of Phosphorus on Other Hydrotreating Catalysts 

Tungsten-based hydrotreating catalysts have been studied much less than the classical molybdenum-based catalysts. It is expected, however, that phosphorus addition should lead to similar effects in both cases since tungsten is chemically similar to molybdenum. Atanasova et al. (101) reported that phosphorus increases the thiophene HDS activity, especially that of a sequentially impregnated NiW—P/Al catalyst. Halachev et al (135) found that a maximum hydrogenation activity for naphthalene conversion is attained when the catalyst contains 0.6 wt% P2O5. Cruz Reyes et al (58) reported that phosphorus on a W/Al catalyst notably enhances gas oil HDS and pyridine HDN. 

Phosphorus m CoMo/C catalysts leads to a significant decrease in thiophene HDS activity (99,100). The weak interaction between the phosph orus 

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VIII. Influence of Phosphorus on Other Hydrotreating Catalysts... 

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