Selection and modification of membrane material is important fundamental research for fluid catalytic cracking (FCC) gasoline desulfurization by membrane process. Solubility parameters of FCC gasoline components and typical polymeric membrane materials were calculated and given out. For thiophene species, which are the primary ones in FCC gasoline, solubility parameters were about 19-21 (J/cm(3))(1/2), while about 14-15 (J/cm3) 112 for most hydrocarbon species in FCC gasoline. The distinct difference in solubility parameter between the two typical species was just the key to fulfill the separation. By the study and analysis of solubility parameter theory, pervaporation (PV) performance and membrane preparation, polyethylene glycol (PEG) was determined as the promising membrane material for gasoline desulfurization. In spite of its desulfurization capacity, PEG needs modification for its easier swelling and unstable PV performance. According to the comparison on PV performance of PEG before and after modification as well as the swelling experiments, crosslinking was an effective modification way for PEG membrane applied in gasoline desulfurization. After crosslinking, not only the sulfur enrichment factor increased distinctly, but also the membrane performance was stable which was the most important point for practical application. Sulfur enrichment factor increased with the increase of amount of crosslinking agent and crosslinking time, while total permeation flux decreased. Unfavorable results occurred with exorbitant crosslinking resulted form excessive crosslinking agent and overlong crosslinking time. Since sulfur enrichment factor was for key consideration, 16% of crosslinking agent amount and 60 min of crosslinking time were more practical. (c) 2006 Elsevier B.V. All rights reserved.