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A novel adsorbent (AMPS-silica) was synthesized by bounding AMPS (2-acrylamido-2-methylpropanesulfonic acid) onto silica surface,which functioned with γ-methacryloxypropyltrimethoxysilane reagent.The adsorbent was characterized by nitrogen adsorption/desorption measurement,thermogravimetric analysis (TGA) and potentiometric titration analysis.The TGA result indicated that the surface modification reactions introduced some organic functional groups on the surface of silica.The surface area of AMPS-silica was 389.7 m~2/g.The adsorbent was examined for copper ion removal in series of batch adsorption experiments.Results showed that the adsorption of Cu~(2+) onto AMPS-silica was pH dependent,and the adsorption capacity increased with the increasing pH from 2 to 6.The adsorption kinetics showed that the Cu~(2+) adsorption was fast and the data fitted well with a pseudo-second order kinetic model.The adsorption of Cu~(2+) on AMPS-silica fitted well both Freundlich and Langmuir isotherms,with r2 = 0.993 and r2 = 0.984,respectively.The maximum Cu~(2+) adsorption capacity was 19.9 mg/g.The involved mechanism might be the adsorption through metal binding with organic functional groups such as carboxyl,amino and sulfonic groups.Cu~(2+) loaded on AMPS-silica could be desorbed in HNO_3 solution,and the adsorption properties remain stable after three adsorption-desorption cycles.