Journal of Membrane Science 280 (2006) 651–658 Pervaporation performance of crosslinked polyethylene glycol membranes for deep desulfurization of FCC gasoline Ligang Lin, Gang Wang, Huimin Qu, Jinrong Yang, Yunfang Wang, Deqing Shi, Ying Kong ∗ State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Dongying 257061, PR China Received 12 December 2005; received in revised form 21 February 2006; accepted 21 February 2006 Available online 29 March 2006 Abstract An crosslinked polyethylene glycol (PEG) membrane was prepared for fluid catalytic cracking (FCC) gasoline desulfurization. Sulfur enrichment factor come to 4.75 and 3.51 for typical FCC gasoline feed with sulfur content of 238.28 and 1227.24 g/g, respectively. Pervaporation performance of membranes kept stable within the long time run of 500 h, which indicated that crosslinked PEG membranes had the property of resisting pollution. Judging from chromatographic analysis, the membranes were more efficient for thiophene species. Effects of operation conditions including permeate pressure, feed temperature, feed flow rate and feed sulfur content level on the pervaporation performance were investigated. Permeation flux decreased with increasing permeate pressure while increased with the operating temperature increase. Sulfur enrichment factor increased firstly and decreased then when permeate pressure and temperature rose. The peak value occurred at 10.5 mm Hg and 358 K for model compounds feed (378 K for FCC gasoline feed). Arrhenius relationship existed between flux and operating temperature. Both sulfur enrichment factor and flux were shown to increase with increasing feed flow rate. Permeation flux increased while sulfur enrichment factor decreased as the feed sulfur content increased, but the influence of increasing sulfur content on pervaporation performance weakened when sulfur content come to 600 g/g. © 2006 Elsevier B.V. All rights reserved. Keywords: Pervaporation; FCC gasoline; Deep desulfurization; PEG; Sulfur 1. Introduction Environmental concerns have resulted in legislation which places limits on the sulfur content of gasoline. In the European Union, for instance, a maximum sulfur level of gasoline has been restricted to 50 ppm by the year of 2005. Sulfur in gasoline is a direct contributor of SO X emissions [1,2]. FCC gasoline is major source of sulfur and contributes heavy amount of the gasoline pool, especially in China. National standard of China for sulfur content of gasoline is 800 g/g, which is far higher than devel- oped countries. Technical development for deep desulfurization of FCC gasoline is urgent and attracting increasing attention. A number of solutions have been suggested to reduce sulfur in gasoline, but none of them proven to be ideal. Since sul- fur in the FCC feed is the prime contributor of sulfur level in ∗ Corresponding author. Tel.: +86 546 8391029/13706364264; fax: +86 546 8391971. E-mail addresses: kongy@hdpu.edu.cn, yingkong@sohu.com (Y. Kong). FCC gasoline, an obvious approach is hydrotreating the feed. While hydrotreating allows the sulfur content in gasoline to be reduced to any desired level, installing or adding the necessary hydrotreating capacity requires a substantial capital expendi- ture and increased operating costs. Further, alkene and cyclic alkane are susceptible to hydrogenation during hydrotreating. This leads to a significant loss in octane number since alkene and cyclic alkane mean higher octane number than paraffin. Application of membrane technology in petrochemical field provides a newly efficient approach for the separation of organic mixture and has gained increasing attention of membrane and petrochemical field. Gasoline desulfurization by membrane pro- cess is newly emerged technology. It is an incorporate process of pervaporation and vapor permeation. The process involves contacting a gasoline feed with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate frac- tion from a sulfur enriched permeate fraction. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur enriched permeate fractions need further treatment by conventional process. Membrane processing offers a number 0376-7388/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.memsci.2006.02.022