Patent ID: 8658814

Claim:
A chemical for chelation of metal ions and separation/recovering of formed chelates, wherein the metal ions are at least bivalent and are contained in water containing and/or water enclosed objects, wherein the chemical corresponds in structure to a following formula wherein either: (1) R in at least one of the positions shown is a straight or branched hydrocarbon chain having 9 to 20 carbon atoms and optionally 1-2 heteroatoms and R is H in the remaining positions and X in at least four of the positions shown is —COOH or a salt thereof and wherein when X is —COOH in four of the positions shown, X is H in the remaining position or (2) R is H in all four positions shown and X in at least one position is —COOR or —CONHR or —CH 2 OR or —COR or —CH 2 OCOR or —CH 2 OCONHR, wherein R is a straight or branched hydrocarbon chain having 9 to 20 carbon atoms and optionally 1-2 heteroatoms, and X in the remaining positions shown is —COOH or a salt thereof.