EXTRACTION BY N,N,N',N-TETRAALKYL -2 ALKYL PROPANE -1,3 DIAMIDES. I. H2O, HNO3 and HClO4

ABSTRACT The extracting properties of substituted diamides were investigated. The auto-association of N,N'-dimethyl dibutyl tetradecyl malonamide (DMDBTDMA) : (C4H9(CH3)NCO)2CHC14H29 in benzene and in TPH (aliphatic hydrocarbon) was shown by NMR using mass-action model. The degree of aggregation depends on the diluent, the diamide concentration and the acidity. The extraction of HNO3 and HClO4 was investigated by distribution measurements and IR spectroscopy. HNO3 extraction is explained by the competing formation of four adducts : whose the equilibrium constants for 0,72 mol.l-1 amide in TPH are 0.167, 0.215, 5.19-10-3 and 3.7-10-4, respectively, on a molal scale. HClO4 is extracted by a reaction involving the competing formation of the two adducts . Their equilibrium constants for 0.697 mol.1-1 amide in TPH are 0.649 and 1.71, respectively, on a molal scale. V(C=O) IR absorption shifts indicate that in are linked by hydrogen bonds, whereas in is transferred from one molecule of acid to one C=O of the DM...