Method for removing heavy metal ions from contaminated water and a porous membrane usable therefor

摘要

A method for simultaneously removing a plurality of different heavy metal ions from contaminated water is disclosed. A plurality of different heavy metal ions can be simultaneously, efficiently removed by filtering contaminated water through a porous membrane comprising a membranous, porous resin matrix and a plurality of side chains chemically bound to both surfaces and pore wall surfaces of the matrix, which side chains each have a chelate group, preferably an iminodiacetic acid group, and terminating the filtration when the concentration of a determinant heavy metal ion in the filtrate reaches a predetermined level. By the method of the present invention, a plurality of different heavy metal ions, such as a cobalt ion and a nickel ion, can be simultaneously, efficiently removed from contaminated water, such as water to be used for and waste water from a nuclear power generator, on a commercial scale.