Lanthanum nitrate complexes aqueous solution

Lanthanum also may be separated from aqueous solutions of rare-earth nitrates by liquid-hquid extraction using a suitable water-immiscible organic hquid such as tributyl phosphate or another complexing agent dissolved in it. 

Aqueous DMF solutions of lanthanum nitrate, chloride, and perchlorate have been investigated by La-NMR spectroscopy as a fimction of the mole fraction Xj of the organic solvent (Tarasov et al. 1986). Both the perchlorate and chloride anions remain in the outer coordination sphere and the cation is preferentially solvated by DMF molecules. In the range 0.14 < Xs < 1, nitrate ions are located both in the outer and inner coordination sphere, forming [La(DMF)j (N03) ] complexes. In solutions with a high content of DMF (1 >Xs > 0.7) the composition of the coordination sphere of La is constant and the predominant complex is [La(DMF)5(N03)2]. ... 

Lead is reported to be almost imique in not forming compounds of this tA pe, basic lead nitrate and chloride being the principal products formed when aqueous hexamethylenetetramine solutions are reacted with lead nitrate and lead chloride, respectively - . Complexes are reported ivith salts of lithium, sodium, potassium, copper,. silver, gold, magnesium, calcium, strontium, barium, zinc, cadmium, mercury, aluminum, titanium, lanthanum, cerium, neodymium, yttrium, erbium, thorium, tin, antimcnj, bismuth, chromium, molybdenum, tungsten, uranium, manganese, iron, cobalt, nickel, platinum, and palladium -... 

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