Separation and recovery of V(IV) from sulfuric acid solutions containing Fe(III) and Al(III) using bis(2-ethylhexyl)phosphoric acid impregnated resin

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

“…Langmuir model is commonly used to describe the uptake of metal ions that occurs on a homogeneous surface by monolayer adsorption without any interaction between the adsorbed ions, and the Freundlich model assumes that the adsorption of metal ions occurs on a heterogeneous surface by monolayer adsorption. The isotherm models are listed as Equations (5) and (6), respectively.…”

“…log Q e = log K F + 1 n log C e (6) where Q e is the amount of adsorbed metal ions per unit mass of SIRs at equilibrium (mg•g −1 ), C e is the concentration of metal ions at equilibrium in raffinate (mg•L −1 ), Q 0 is the adsorbent capacity (possible maximum amount of metal ions adsorbed per unit mass of SIRs, mg•g −1 ), K L is Langmuir isothermal adsorption equilibrium constant (L•mg −1 ), and K F and n are the Freundlich constants for adsorption capacity and adsorption intensity, respectively. The fitting results of Langmuir and Freundlich isotherm model for N-TIRs and NIRs are shown in Figure 7, and the parameters of Langmuir and Freundlich isotherm models are listed in Table 2.…”

“…Solvent-impregnated resins (SIRs) that were prepared by incorporating extractants onto polymeric matrix have been widely applied in the fields of separation and purification for metals [1][2][3] and organics [4,5] from aqueous solutions, due to their high selectivity, operational simplicity, and environmental friendliness [6,7], which can be traced back to the pioneering work that was conducted by Warshawsky [8], Grinstead [9], and Kroebel and Meyer [10] in the early 1970s. Thus, the preparation and application of the SIRs in analytical and environmental chemistry, hydrometallurgy, and radiochemistry fields are still intensive research topics [11].…”

“…However, there are some problems that are embedded in SIRs, such as time-consuming of the impregnation process for the extractants impregnating onto the macroporous matrix, long time of the adsorption equilibrium and low adsorption capacity of the SIRs for metal ions, which may impede the industrial application of SIRs. For instance, Liang et al [6] investigated the adsorption and separation of V(IV) from the vanadium leaching solution containing Fe(III) and Al(III) with D2EHPA-impregnated resins (DIRs). It was found that the impregnation equilibrium time exceeds 24 h and the adsorption capacity of the DIRs for vanadium (IV) is about 16.0 mg•g −1 after a 18 h long reaction.…”

Vanadium Transitions during Roasting-Leaching Process of Vanadium Extraction from Stone Coal

“…However, most vanadium in stone coal exists as V(III) replacing Al(III) from dioctahedral structure as isomorphism in mica group minerals [3], which is generally recovered by roasting with sodium additive at a high temperature [4]. After that, the vanadium is liberated from crystal structure and converted to water or acid soluble vanadate [5], which is subsequently recovered by water leaching and/or acid leaching, ion purification, vanadium precipitation, and calcination [6][7][8]. For the process of vanadium extraction from stone coal, the vanadium recovery by the roasting-leaching procedure is around 65-75%, while for other procedures, such as ion exchange, solvent extraction, and vanadium precipitation, the vanadium recoveries are more than 97% [9,10].…”