EXTRACTION EQUILIBRIA OF 4-(2-PYRIDYLAZO)RESORCINOLATOVANADIUM(V) COMPLEXES WITH QUATERNARY AMMONIUM SALT AND WITH TRIOCTYLPHOSPHINE OXIDE

Extraction equilibria for vanadium(V) complexes with 4-(2-pyridylazo)resorcinol (PAR, H2L) at 25°C were investigated in the Na2SO4 solution with the ionic strength of 0.1. The complexes are extracted into chloroform either as an ion-pair with behzyldimethyltetradecyl-ammonium (Q+) cation, Q[VO2L](λ=560nm, ε=3.SS×l04dm3.mol-1.cm-1). or as an adduct complex with trioctylphosphine oxide (topo), [VO2(HL)(topo)] (λ = 560nm, λ=l, 40×104 dm3 mol-1.cm-1). The extraction constants of these complexes were estimated as, The adduct formation constant in chloroform was calculated to be, The equilibrium diagram for the extraction of the vanadium(V)-PAR complexes were p.o-posed on Fig. 8. © 1979, The Chemical Society of Japan. All rights reserved.