A high qualified polysulfone hollow fiber affinity membrane modified with mercapto as chelating groups was prepared by phase inversion technology using chlormethyl polysulfone (CMPSF) as membrane matrix materials, through the reaction between thiourea and CMPSF hollow fiber matrix membrane to afford the methyl isothiourium polysulfone and was then alkaline hydrolyzed. The adsorption isotherms of the hollow fiber affinity membrane chromatography for Hg2+ were determined, and the effects of mobile phase conditions and the operating parameters on removal performance of the hollow fiber affinity membrane chromatography for Hg2+ were also investigated. The experimental results showed that adsorption isotherms of Hg2+ could be described by the Langmuir isotherm. Addition of NaCl into feed solution for the increase of ionic strength was harmful for the removal of Hg2+. The recovery of Hg2+ decreased at low pH and the optimum range of pH was from 5.0 to 7.0. The feed concentration had a remote effect on recovery of Hg2+ at the specified loading amount of Hg2+, and the Hg2+ could be removed from different concentration feed solution by the hollow fiber affinity membrane chromatography. The increase of feed flow rate led to slight decrease of recovery of Hg2+ at the specified loading amount of Hg2+. The hollow fiber affinity membrane chromatography Could be operated at height feed flow rate and a large scale removal of Hg2+ Could be realized. With the increase of load amount, Hg2+ recovery decreased, but the saturation degree of hollow fiber affinity membrane chromatography increased. According to required recovery of Hg2+ and the saturation degree of membrane chromatography, the optimum loading amount of Hg2+ should be selected in the actual removal of Hg2+. (c) 2006 Wiley Periodicals, Inc.