Referring to a copolymer comprising monomeric units derived from at least one C monomer of formula (I): H2C = C (R1) -R2-O (-CH2-CH2-O-) k-CH2-CH2-R3, where R1 is H or methyl; R2 is absent, or is -C (= O) -, -CH2-, among others; R3 is H or -OH; and k is a number from 0 to 300. This copolymer is used as binders for the pelletization of a metal-containing mineral such as Fe-containing minerals, preferably.