Applications of Hydrofining

As mentioned earlier. Hydrofining may be applied to a host of products to improve their quality. Subsequent paragraphs will show the results that can be obtained. 

Hydrofining is applied to virgin naphthas mainly in the form of a pretreatment step for the feed to catalytic reformers (Powerforming). Sulfur levels of 5 parts per million (ppm) or less are required to avoid deactivation of the platinum reforming catalyst. 

Virgin naphtha hydrofining processing conditions have been standardized at 550°F, 4 V/hr/V, 300-400 psig and 400-500 SCF/B of 70% H treat gas. Such conditions will make a 4 ppm sulfur product of most stocks of interest. 

On cracked naphthas. Hydrofining provides not only desulfurization, but also improvements in gum, stability, and engine cleanliness characteristics. 

Hydrofining has all the advantages of acid treating without the disadvantages. For example, acid treating does not readily remove refractory sulfur compounds such as thiophene the treated products must be rerun to remove polymers with a consequent yield loss and disposal of the acid sludges is a serious problem. 

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