The invention relates to a particular polymer which is derived from a
copolymer polysaccharide formed by a main chain comprising similar or
different anhydrohexose units and branches including at least one neutral
or anionic anhydropentose and/or anhydrohexose unit. Moreover, the
invention relates to the use of said polymer in the treatment of aqueous
media, in particular the treatment of aqueous effluents containing heavy
metals, the treatment of waste water, drinking water and for sludge
conditioning. Said derivative polymer comprises one or more units bearing
an oxime function at least at position C2.
