Interaction between TBP and D2EHPA during Zn, Cd, Mn, Cu, Co and Ni solvent extraction: A thermodynamic and empirical approach

Extraction Kinetics of Ni(II) in the Ni<sup>2+</sup>- SO<sub>4</sub><sup style="margin-left:-7px;">2-</sup>-Ac<sup>-</sup>(Na<sup>+</sup>, H<sup>+</sup>)-Cyanex 272 (H<sub>2</sub>A<sub>2</sub>)-Kerosene-3% (v/v) Octan-1-ol System Using Single Drop Technique

“…Equation 12gives the slow reaction step occurring in the bulk aqueous phase as: (13) In this experimental parametric condition, Ni 2+ extraction by Cyanex 272 is therefore chemically controlled and this statement is supported by high E a (56 kJ/mo obtaine lcr of (0.05 mol/L) and Ac (0.25 mol/L). hemically controlled rate-determining step: may occur either by an S or S N 2 mechanism, the bimolecular reactio…”

“…Previously, organo-phosphorous extractants like D2EHPA [1][2][3][4][5][6][7][8][9][10], Cyanex 272 [1][2][3][4][5][6][11][12][13][14][15][16], EHEHPA or PC 88A [1][2][3][4][5]17,18], M2EHPA [9], TBP [2,8,9], Cyanex 301 [4,7,11,16,[19][20][21] and Cyanex 302 [4,7,11,14], TOPS 99 [12,22], TIBPS [22], etc. have been used for Ni 2+ /Co 2+ separation.…”

A High-Efficiency Approach for the Synthesis of N235-Impregnated Resins and the Application in Enhanced Adsorption and Separation of Vanadium(V)

“…A literature shows that the characteristic vibration bands of P=O, 1281 cm −1 , would appear in the SIRs containing TBP [17]. It is obviously found that the characteristic adsorption peak of N235 (C-N bonds, 1099 cm −1 ) shifts to the lower wavenumber (1096 cm −1 ) and the intensity of the C-N bonds decreases (Figure 4a), and the P=O stretching bands also shifts to lower wavenumber 1263 cm −1 (Figure 4b), which may be attributed to that N235 is involved with TBP [23]. Therefore, it may be concluded that an interaction between TBP and N235 has occurred during the impregnation process, rendering the improvement of the impregnation rate and the impregnation ratio of the extractants onto the resins.…”

“…The results indicate that the impregnation process of the N-TIRs accomplish faster (about 5 min) than that of the NIRs (about 240 min) [19], attributing to the addition of TBP [22]. The "interface modifier", TBP, can improve the phase separation rate, i.e., accelerate the molecular motion rate between the aqueous and organic phases [14,23], thus the addition of TBP can obviously shorten the impregnation equilibrium time of the N-TIRs. As is presented in Figure 3, the adsorption capacity of N-TIRs for V(V) firstly slowly declines and then keeps constant with the increasing impregnation ratio.…”

Base Metal Ion Extraction and Stripping from WEEE Leachate by Liquid-liquid Extraction

“…15 TBP improves metal extraction efficiency in co-operating with D2EHPA because tetrahedral or octahedral structure of metal-D2EHPA complex in the organic phase consists of four large extractant molecules in the coordination sphere and cause spherical hindrance. [18][19][20][21] An extractant such as TBP with Lewis base properties, relatively smaller molecule and low extraction ability could be exchanged with two of these molecules. [22][23][24] Complexation reaction between metal cation and carrier ligand involves an initial formation of "inner sphere" in which water molecules that intervene metal carrier complexation and (replaced between metal and ligand molecules) have been displaced, and inner sphere metal-ligand complexes are formed.…”