Removal of sulfur‐containing compounds from Fluid Catalytic Cracking unit (FCC) gasoline by pervaporation process: Effects of variations in feed characteristics and mass transfer properties of the membrane

Abstract

AbstractAnalyzing the effects of feed characteristics and membrane transport properties are important for designing the industrial‐scale pervaporative desulfurization plants. In this study, a new method to analyze the effects of feed composition and membrane characteristics has been proposed, where these properties are represented by average vapor pressure and average permeance coefficient. Spiral wound module geometry is used in this study for more realistic industrial‐scale predictions. Results suggested that module performance in terms of stage cut and enrichment factor improved with increasing selectivity of the membrane. However, this effect was profound at lower selectivity (<5) and became negligible at higher selectivity (>10). Moreover, results also depicted that the increase in feed temperature increased enrichment factor when selectivity was low (<2.5), but this trend was reversed when selectivity was greater than 2.5. At a constant membrane selectivity, an increase in permeability reduced the enrichment factor. Thus, membrane selectivity should improve along with membrane permeability for better results. The pervaporation process was found more beneficial for removing highly volatile low molecular weight sulfur‐containing compounds. Finally, feed channel temperature drop and permeate channel pressure drop followed the trend of stage cut in all simulations. Therefore, the lower stage cut may improve module efficiency.