Tetraazadodecane based chelating agents for separation of rare earth elements and method therefor

A compound of general formula (I)

• for separation of rare earth elements by precipitation,
• wherein
• R1 is selected from the group consisting of H;
• —CH2COOH;
• R2, R3, R4, R5 and R6 are independently selected from the group consisting of H;
• OH;
• —NO2;
• —COOH;
• phenyl;
• and/or R2 and R3 together with two neighbouring carbon atoms of the aromatic ring form a sixmembered aromatic ring;
• and/or R3 and R4 together with two neighbouring carbon atoms of the aromatic ring form a sixmembered aromatic ring;
• and/or R4 and R5 together with two neighbouring carbon atoms of the aromatic ring form a sixmembered aromatic ring;
• and/or R5 and R6 together with two neighbouring carbon atoms of the aromatic ring form a six-membered aromatic ring.