The invention provides methods and compositions for separating metals from a liquid medium, the method uses a copolymer derived from at least two monomers: acrylic-x and an alkylamine, wherein said polymer is modified to contain a functional group capable of scavenging one or more compositions containing one or more metals are disclosed. The treated liquid is then passed through a filtration system. The scavenging effect of the combination of the treatment with the filtration is unexpectedly greater than the sum of its parts. MS