Liquid-liquid extraction of zirconium(IV) from sulphuric acid medium using a binary mixture of tri-n-octylamine and Cyanex923 in kerosene European Journal of Chemistry 13 (3) (2022) 273-278 European Journal of Chemistry ISSN 2153-2249 (Print) / ISSN 2153-2257 (Online) – Copyright © 2022 The Authors – Atlanta Publishing House LLC – Printed in the USA. This work is published and licensed by Atlanta Publishing House LLC – CC BY NC – Some Rights Reserved. https://dx.doi.org/10.5155/eurjchem.13.3.273-278.2273 European Journal of Chemistry View Journal Online View Article Online Liquid-liquid extraction of zirconium(IV) from sulphuric acid medium using a binary mixture of tri-n-octylamine and Cyanex923 in kerosene Amit Sahoo , Jaykishon Swain , and Bhikari Charana Bhatta * Department of Chemistry, Odisha University of Technology and Research, Techno Campus, Mahalaxmivihar, Bhubaneswar-751029, Odisha, India * Corresponding author at: Department of Chemistry, Odisha University of Technology and Research, Techno Campus, Mahalaxmivihar, Bhubaneswar-751029, Odisha, India. e-mail: bcbhatta14@gmail.com (B.C. Bhatta). 10.5155/eurjchem.13.3.273-278.2273 Received: 11 March 2022 Received in revised form: 04 May 2022 Accepted: 07 May 2022 Published online: 30 September 2022 Printed: 30 September 2022 The extraction behaviour of zirconium(IV) from sulfuric acid medium has been studied with a binary mixture of tri-n-octyl amine (TOA) and Cyanex923 (a mixture of four trialkyl phosphine oxides) in kerosene using a novel liquid-liquid extraction method. Quantitative extraction of zirconium(IV) with binary mixture of Cyanex923 and TOA in kerosene was studied by changing different parameters such as acid variation, extractant variation, effect of chloride ion concentration, effect of temperature, metal concentration variation, diluent effect, and pH effect. The percentage of extraction of zirconium(IV) decreased when the concentration of Cyanex923 and TOA increased. The percentage of zirconium(IV) was observed as 97.56% in a binary mixture of 0.007 M Cyanex923 and 0.06 M TOA. Kerosene was found to be an effective diluent for the extraction of zirconium(IV) with 97.56% extraction using a binary mixture of Cyanex923 and TOA. In addition, the stripping of the zirconium(IV) metal ion in the organic phase was also examined. TOA Kerosene Cyanex923 Zirconium(IV) Sulphuric acid Solvent extraction Cite this: Eur. J. Chem. 2022, 13(3), 273-278 Journal website: www.eurjchem.com 1. Introduction Zirconium (Zr) is a soft, lustrous, ductile, grayish-white, malleable transition metal that is solid at room temperature and at low purities becomes hard and brittle [1]. Zirconium is an extremely corrosion-resistant metal by alkali, saltwater, acids, and other agents [2]. Even though zirconium and hafnium have similar chemical properties, they differ in neutron- absorbing properties that lead to the separation of hafnium from zirconium for nuclear reactor applications [3]. Zirconium is also used as the cladding material for nuclear reactor fuels [4]. Zirconium is a heat-resistant metal. In space vehicle parts, materials fabricated from zirconium metal and its oxide (ZrO2) are used [3]. The compounds inhold zirconium metal are used in several biomedical applications, such as dental implants and other restorative practices, middle ear ossicular chain reconst- ruction, knee and hip replacements, etc. [5]. Solvent extraction of Zr(IV) from acid chloride medium by using a commercial extractant LIX84-IC was studied by Reddy et al. [6]. Using HCl and high concentrations of green amic acid, N,N-di-2-ethylhexyl diglycolamic acid (D2EHDGAA), Ma et al. developed a novel strategy for separating Zr ions and Hf ions. Based on these results, it was concluded that D2EHDGAA in HCl solution performed well at separating Zr ions and Hf ions. Using 2.5 mol/L HCl, the zirconium oxychloride hydrolysate and simulation liquid had separation factors of 11.4 and 34.5, respecttively [7]. Co-extraction and separation of Zr and Hf using primene JM-T extractant as long-chain primary amine from the sulfuric acid medium were carried out by El-Yamani et al. [8]. The extraction of Zr from the sulfuric acid medium by using long-chain aliphatic amines was studied by Sato et al. [9]. Secondary amines are more effective extractants than tertiary amines for Zr was observed by Sato et al. [9]. Using Aliquate- 336 as an organic solvent, Zr(IV) extraction through the sulfuric acid medium was carried out by Sato et al. [10]. Through solvent extraction technique, by utilizing a new extractant, bis(2- ethylhexyl)-1-(2-ethylhexylamino)propylphosphonate (BEAP or B) the separation of zirconium from hafnium from sulfate medium was completed by Chen et al. [11]. They reported that the extraction of both zirconium and hafnium are exothermic processes and the separation factor of Zr over Hf was 6.8 at 25 °C. The equilibrium studies in the extraction of Zr(IV) through sulfate medium using di(2-ethylhexyl)phosphoric acid (D2EHPA, HR) acid in kerosene were carried out by Juang et al. [12]. They reported that at higher loading ratios of D2EHPA (0.10 ˂ α ˂ 0.32) and at low loading ratios of D2EHPA (α ˂ 0.09) the extracted species were found to be ZrR4, ZrR4(HR)3 and ZrR4, ZrR4(HR), respectively. With Alamine 336 (10%) in kero- ABSTRACT RESEARCH ARTICLE KEYWORDS https://dx.doi.org/10.5155/eurjchem.13.3.273-278.2273 https://www.eurjchem.com/ https://dx.doi.org/10.5155/eurjchem.13.3.273-278.2273 mailto:bcbhatta14@gmail.com http://www.eurjchem.com/ https://crossmark.crossref.org/dialog/?doi=10.5155/eurjchem.13.3.273-278.2273&domain=pdf&date_stamp=2022-09-30 274 Sahoo et al. / European Journal of Chemistry 13 (3) (2022) 273-278 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.3.273-278.2273 N CH3H3C CH3 TOA PH3C CH3 CH3 O Cyanex923 (Main Component) Figure 1. The structure of TOA and Cyanex923 (main component). sene, Junior et al. processed the Brazilian bauxite residue to separate scandium and zirconium. According to them, the D2EHPA and TBP mixture had the same scandium separation factor as Cyanex923 [13]. By varying the concentrations of acid, solvent, and aqueous Zr(IV), the extraction of Zr(IV) using high molecular amines from a sulfuric acid medium was carried out by Schrotterova et al. [14]. Using amine-based extractants such as Aliquat336, Alamine300, Alamine308, TEHA, and Alamine- 336, Wang and Lee studied the extraction and separation of Zr and Hf from the sulfate medium [15] and Alamine308 got the highest separation factor of 12.4 at 0.5 M sulfuric acid medium. The solvent extraction of trace level Zr and Hf from HCl, HF, HNO3, and H2SO4 media by using trioctylamine (TOA) was demonstrated by Das and Lahiri [16]. They reported that for quantitative extraction of the individual elements at their trace level, TOA was a very effective extractant. Onishi et al. [17] studied the spectrophotometric determination of microgram amounts of zirconium, thorium, uranium, and rare earths with arsenazoIII by using theroyltrifluoroacetone (TTA) and tri-n- octylamine in xylene from HCl medium. Wu et al. proposed a pathway for synergistic extraction of Hf over Zr using a binary mixture extractant, i.e., TOPO and N1923 from thiocyanic acid. The efficiency of their process was found to be 86.3% [18]. Solvent extraction behavior of trace level tantalum and niobium by using trioctylamine from sulphuric acid and hydrofluoric acid media that have greater affinities towards niobium and tantalum with TOA was studied by Das et al. [19]. Using a binary mixture of N,N-octylaniline, and trioctylamine in xylene, Petkar et al. [20] investigated the liquid-liquid extraction of Bi(III) from thiocyanate and sulfuric acid medium. By using 4-(5- nonyl)pyridine oxide and trioctylamine oxide in nitric acid and sulphuric acid medium, the extraction of zirconium was investigated by Ejaz [21]. Through solvent extraction techni- ques, the extraction and separation of Zr and Hf from the nitric acid medium with some phosphine oxide extractants such as Cyanex923, Cyanex921, and Cyanex925 in kerosene were reported by Nayl et al. [22]. They reported that, in Cyanex921, Cyanex925, and Cyanex923, the extraction rate of Zr (IV) and Hf(IV) is fast and also suggested that the extraction increases with increasing temperature, implying that the reaction is endothermic. An evaluation of the inertness and performance of organophosphorus-based extraction agents DiOPA, Ionquest 801, and D2EHPA was conducted using both dispersive extraction and per traction solvent extraction (SX) to achieve selective extraction of Zr and Hf from an acid solution of (NH4)3Zr(Hf)F7 [23]. The separation of Zr and Hf with a mixture of Cyanex923 and TBP extractants in the organic phase by using the solvent extraction technique was proposed by Taghizadeh et al. [24]. Using the solvent extraction process, Gupta et al. [25] investigated the extraction and recovery of Zr from zircon using Cyanex923 extractant in toluene. Zirconium metal extraction in greater quantities is essential than in trace levels. To determine the amounts of metal in aqueous and organic solutions, the solvent extraction method is a prominent effective method. The important aim of solvent extraction is to recover the metal from its solution using a suitable extractant. In this work, the quantitative extraction of Zr(IV) by the solvent extraction method operating various parameters such as the acidity of the aqueous phase, the molarity of the extractant, the concentration of chloride ions, the diluents, the temperature and the concentration of the metal of the aqueous phase, the pH has been investigated from the sulphuric acid medium using the binary mixture of Cyanex923 and TOA (Figure 1). The loaded organic phase containing metal has been stripped with TOA and Cyanex923 extractants to find the best strippant for the extraction system. 2. Experimental 2.1. Reagents A 0.01 M ZrOCl2·8H2O (Merck) stock solution was prepared by dissolving in double-distilled water. To restrict further hydrolysis, one mL of concentrated HCl was added to the metal stock solution. Distilled kerosene was used as an organic diluent. TOA (tri-octylamine) (Merck) and a mixture of four trialkyl phosphine oxides, i.e., Cyanex923 (Merck) were used as a commercial extractant without further purification. All other reagents used were of analytical reagent grade. 2.2. Process 10 mL of solutions containing Zr(IV) (0.001 M) in H2SO4 and the organic phase containing Cyanex923 and TOA in kerosene were shaken in a separating funnel. In twenty minutes, complete equilibrium was achieved. After five minutes, the phases were settled, and then they were disengaged. The concentration of Zr(IV) in the aqueous phase before and after extraction was determined using the Arsenazo (III) method [18] using a PerkinElmer UV-visible spectrophotometer. The ratio of the equilibrium concentration of Zr(IV) inorganic phase and that in the aqueous phase was taken in the calculation of the distribution coefficient (D). The concentration of Zr(IV) in the organic phase was calculated by using the mass balance, i.e., the difference in metal concentration in the aqueous phase before and after the extraction. Spectrophotometrically, the absorbance of the metal was measured [18] before and after extraction, from which the distribution ratio was calculated as follows: D = AbsB.E.− AbsA.E. AbsA.E. (1) where AbsB.E. = Absorbance before extraction and AbsA.E. = Absorbance after extraction. The distribution ratio was observed as the ratio of the equilibrium concentration of metal in the organic phase to that in the aqueous phase. D=[M]org [M]aq (2) where [M]aq and [M]org are the metal concentrations in the aqueous and organic phase after extraction, respectively. Sahoo et al. / European Journal of Chemistry 13 (3) (2022) 273-278 275 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.3.273-278.2273 Figure 2. Impact of H2SO4 concentration on the extraction percentage of 0.001 M Zr(IV) using the binary mixture of 0.01 M Cyanex923 and 0.1 M TOA in kerosene. (a) (b) Figure 3. (a) Plot of log D versus log [Cyanex923] in the extraction of 0.001 M Zr(IV) from 1 M H2SO4 within the sight of a changing concentration of Cyanex923 at fixed 0.1 M TOA in kerosene and (b) Plot of log D versus log [TOA] in the extraction of 0.001 M Zr(IV) from 1 M H2SO4 within the sight of a varying concentration of TOA at fixed 0.007 M Cyanex923 in kerosene. From the D values, the percentage of extraction (%E) was calculated as %E = 100 D D+1 (3) 3. Results and discussion 3.1. Effect of acid concentration 0.001 M Zr(IV) was extracted with 0.01 M Cyanex923 and 0.10 M TOA in kerosene by varying the concentration of H2SO4 from 1 to 7 M. The percentage of extraction was 96.61% with 1 M H2SO4 and then decreased to 36.98% with 7 M H2SO4. Extraction based on aqueous phase acidity was observed due to the more amine salt formation that extracts the metal complex [25]. From the observed data, a continuous decreasing plot is obtained which is shown in Figure 2. 3.2. Effect of extractant concentration By keeping the concentration of TOA constant (0.1 M), the extraction of 0.001 M Zr(IV) was carried out (1 M H2SO4) in the binary mixture of extractant and changing the concentration of Cyanex923 from 0.003 to 0.008 M in kerosene. The percentage of Zr(IV) extraction decreased from 97.56 to 47.69% with a decrease in the concentration of Cyanex923 from 0.008 to 0.003 M in kerosene. The plot of log D versus log [Cyanex923] shows a slope of 3.8509 (Figure 3). At a fixed concentration of Cyanex923 (0.007 M), the effect of TOA on the 0.001 M Zr(IV) extraction was studied by changing the concentration of TOA from 0.01 to 0.06 M. The percentage of extraction increased from 53.16 to 97.56% with the increase in concentration from 0.01 to 0.06 M. The plot of log D versus log[TOA] yields a slope of 2.1203 (Figure 3). 3.3. Effect of chloride ion concentration On the extraction of 0.001 M Zr (IV), the effect of chloride ion concentration (1 M H2SO4) using 0.007 M Cyanex923 and 0.06 M TOA was studied. The percentage of Zr (IV) extraction decreased from 96.26 to 93.87%, from 96.28 to 92.92%, and from 97.12 to 94.79% (Figure 4) within the increase in the concentration of NH4Cl, KCl, and NaCl, respectively, increasing the chloride ion concentration from 0.001 to 0.080 M. 3.4. Effect of temperature The effect of temperature on the extraction of 0.001 M Zr(IV) (1 M H2SO) was carried out in the temperature range 318-358 K using a binary mixture of 0.007 M Cyanex923 and 0.06 M TOA in kerosene. The percentage of extraction of Zr(IV) decreased from 91.91 to 87.84% with an increase in temperature. By using Equation (4), the extraction equilibrium constants (Keq) at different temperatures have been calculated. The plot of log Keq versus 1000/T is linear (Figure 5). Enthalpy change (∆H) and entropy change (∆S) were calculated to be - 10.2 kJ/mol and 10.84 J/K.mol using Van’t Hoff equation. It ensures that the extraction process is exothermic, accompanied by an increase in randomness. 𝐾𝐾eq = [R3NHZrOSO4](org)×[R3PHZrOSO4](org) [ZrOCl2](aq) [R3NHSO4](org)×[R3PHSO4](org) (4) 0 10 20 30 40 50 60 70 80 90 100 0 1 2 3 4 5 6 7 8 Ex tr ac tio n, % [H2SO4], M y = 3.8509x + 9.6908 R² = 0.9376 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 -2.6 -2.5 -2.4 -2.3 -2.2 -2.1 -2.0 -1.9 Lo g D Log [Cyanex923] y = 2.1203x + 4.283 R² = 0.9873 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 -2.2 -2.0 -1.8 -1.6 -1.4 -1.2 -1.0 Lo g D Log [TOA] 276 Sahoo et al. / European Journal of Chemistry 13 (3) (2022) 273-278 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.3.273-278.2273 Figure 4. Impact of chloride ion concentration on the extraction of 0.001 M Zr(IV) from 1 M H2SO4 using the binary mixture of 0.007 M Cyanex923 and 0.060 M TOA in kerosene. Figure 5. Plot of log Keq versus 1000/T for the extraction of 0.001 M Zr(IV) from 1 M H2SO4 using the binary mixture of 0.007 M Cyanex923 and 0.060 M TOA in kerosene. Figure 6. Impact of metal ion concentration on the extraction of 0.001 M Zr(IV) from 1 M H2SO4 using the binary mixture of 0.007 M Cyanex923 and 0.060 M TOA in kerosene. 3.5. Effect of metal ion concentration Using a binary mixture of 0.007 M Cyanex923 and 0.060 M TOA, the extraction of Zr(IV) (1 M H2SO4) has been studied by decreasing the concentration of Zr (IV) metal ion from 0.0001 to 0.0005 M (Figure 6). The percentage of extraction was increased from 83.63 to 95.72% with the decrease in metal ion concentration up to 0.0005 M and thereafter remains constant. 3.6. Effect of diluent For a successful solvent extraction system, there are two vital aspects, that is, the selection of extractants and diluents [18]. The influence of diluents on the distribution of metal is correlated with the physicochemical properties of an organic solvent such as dipole moment, dielectric constant, solubility parameter, etc. [18]. Using a binary mixture of 0.007 M Cyanex923 and 0.060 M TOA, the extraction of Zr(IV) has been studied in various organic diluents such as kerosene, benzene, diethyl ether, xylene, carbon tetrachloride, and chloroform. When kerosene was used as a diluent, the percentage of extraction was the maximum as shown in Table 1. Due to easy availability, low cost, and toxicity, kerosene was selected as the diluent for the extraction study. 90 91 92 93 94 95 96 97 98 99 100 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 Ex tr ac tio n, % [Cl-], M KCl NH4Cl NaCl y = 0.5328x + 0.5663 R² = 0.9346 2.00 2.05 2.10 2.15 2.20 2.25 2.30 2.8 2.8 2.9 2.9 3.0 3.0 3.1 3.1 3.2 3.2 Lo g K 1000/T 80 82 84 86 88 90 92 94 96 98 100 0.0000 0.0001 0.0002 0.0003 0.0004 0.0005 0.0006 Ex tr ac tio n, % Metal concentration, M Sahoo et al. / European Journal of Chemistry 13 (3) (2022) 273-278 277 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.3.273-278.2273 Table 1. Impact of diluents on the extraction of 0.001 M Zr(IV) using the binary mixture of 0.007 M Cyanex923 and 0.060 M TOA from 1 M H2SO4. Diluents Distribution ratio Extraction, % Kerosene 39.993 97.56 Benzene 28.697 96.63 Diethyl ether 23.973 95.99 Xylene 33.397 97.09 Carbon tetrachloride 10.968 91.64 Chloroform 4.675 82.37 Figure 7. Impact of pH on the extraction of Zr(IV) from 1 M H2SO4 using the binary mixture of 0.007 M Cyanex923 and 0.060 M TOA in kerosene. (a) (b) Figure 8. (a) Plot of % Stripping versus [HNO3] from the stacked binary organic phase of 0.007 M Cyanex923 and 0.060 M TOA for recuperation of Zr(IV) in kerosene and (b) Plot of % Stripping versus [Na2CO3] from the stacked binary organic phase of 0.007 M Cyanex923 and 0.060 M TOA for recovery of Zr(IV) in kerosene. 3.7. Effect of pH The extraction of 0.001 M Zr (IV) using a binary mixture of 0.060 M TOA and 0.007 M Cyanex923 in kerosene was studied by changing the pH of the aqueous solution from 0.6 to 1.3. The percentage of extraction of Zr(IV) decreased from 97.54 to 81.94% was observed with an increase in pH from 0.6 to 1.3. The detailed data are shown in Figure 7. 3.8. Stripping The metal can be extracted back from the loaded organic phase. This extraction process becomes commercially impor- tant [18]. The effect of various concentrations of strippants was studied on the stripping of metal ions from the loaded organic solvent at 298 K and a phase ratio of 1:1. Zr (IV) ions were extracted from 1 M H2SO4 using a binary mixture of 0.007 M Cyanex923 and 0.060 M TOA. It was observed that the stripping was 100% with 2.6 M HNO3 and 2 M Na2CO3 in one step (Figure 8). 3.9. Extraction equilibrium The possible extraction mechanism of Zr(IV) from sulphuric acid (H2SO4) medium with a binary mixture of Cyanex923 and TOA in distilled kerosene appears to proceed through the protonation of Cyanex923 (R3P) and TOA (R3N) forming R3PHSO4 and R3NHSO4, respectively, followed by extraction of (R3NH) ZrOCl2 and (R3PH)ZrOSO4(org) species into the organic phase [25]. Under the experimental conditions studied and from the slope analysis results, the extraction of Zr(IV) from high acid chloride medium with the binary mixture of Cyanex923 and TOA may be described by the following Equations: 2 ZrOCl2 (aq) + R3NHSO4 (org) + R3PHSO4 (org) ⇋ R3NHZrOSO4 (org) + R3PHZrOSO4 (org) (5) The extraction equilibrium constant is given as 𝐾𝐾𝑒𝑒𝑒𝑒 = [𝑅𝑅3𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁4](𝑜𝑜𝑜𝑜𝑜𝑜)×[𝑅𝑅3𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁4](𝑜𝑜𝑜𝑜𝑜𝑜) [𝑁𝑁𝑁𝑁𝑁𝑁𝑍𝑍𝑙𝑙2](𝑎𝑎𝑎𝑎)×[𝑅𝑅3𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁4](𝑜𝑜𝑜𝑜𝑜𝑜)×[𝑅𝑅3𝑃𝑃𝑁𝑁𝑁𝑁𝑁𝑁4](𝑜𝑜𝑜𝑜𝑜𝑜) (6) ⇒𝐾𝐾eq = D [R3NHSO4](org)×[R3PHSO4](org) (7) where D = [R3NHZrOSO4](org)×[R3PHZrOSO4](org) [ZrOCl2](aq) (8) 4. Conclusions This work highlights the extraction of 0.001 M Zr(IV) from 1 M H2SO4 using a binary mixture of 0.007 M Cyanex923 and 0.060 M TOA in kerosene is highest i.e., 97.56%. The extraction of Zr(IV) decreases with the increase in acid concentration and pH of the metal solution but increases with the increase in the extractant concentration and the metal ion concentration. The 80 82 84 86 88 90 92 94 96 98 100 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 Ex tr ac tio n, % pH 0 10 20 30 40 50 60 70 80 90 100 0.0 0.5 1.0 1.5 2.0 2.5 3.0 St rip pi ng , % [HNO3], M 0 10 20 30 40 50 60 70 80 90 100 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 St rip pi ng , % [Na2CO3], M 278 Sahoo et al. / European Journal of Chemistry 13 (3) (2022) 273-278 2022 – European Journal of Chemistry – CC BY NC – DOI: 10.5155/eurjchem.13.3.273-278.2273 extraction of Zr(IV) from 1 M H2SO4 decreases with an increase in temperature i.e., 318-358 K. The positive influence of tempe- rature shows the extraction to be exothermic. The positive value of change in entropy shows an increase in randomness. The extraction of Zr(IV) from 1 M H2SO4 decreases with the increase in chloride ion concentration due to the extraction of chloro complex of zirconium with a binary mixture of TOA and Cyanex923. 100% of Zr(IV) is stripping out from the binary mixture of TOA and Cyanex923 with 2.6 M HNO3 and 2 M Na2CO3. The percentage of Zr(IV) extraction decreases with an increase in the pH of the aqueous solution. Zr(IV) extraction from 1 M H2SO4 using a binary mixture of Cyanex923 and TOA has been studied in increasing order in different organic diluents, that is, Kerosene > Xylene > Benzene > Diethyl ether > Carbon tetrachloride > Chloroform. The separation studies of Zr (IV) from Hf (IV) may be undertaken under the condition where the extraction of Zr (IV) is quantitative (> 95%). Acknowledgement The authors express their sincere thanks to the authorities of Odisha University of Technology and Research, Bhubaneswar, for their constant encouragement to carry out this research work. The authors thankful to Head of Department, Department of Chemistry, Odisha University of Technology and Research and highly grateful to Miss Sakuntala Padhi for her continous support to carry out this research work. Disclosure statement Conflict of interest: The authors declare that they have no conflict of interest. Ethical approval: All ethical guidelines have been adhered. Sample availability: Samples of the compounds are available from the author. CRediT authorship contribution statement Conceptualization, Methodology, Software, Validation, Formal Analysis, Investigation, Resources, Data Curation, Writing - Original Draft, Writing - Review and Editing, Visualization, Funding acquisition, Supervision, Project Administration: Amit Sahoo, Jaykishon Swain, and Bhikari Charana Bhatta. ORCID and Email Amit Sahoo amitsahoochemistry@gmail.com https://orcid.org/0000-0002-7480-658X Jaykishon Swain jaykishon11@gmail.com https://orcid.org/0000-0002-2117-9711 Bhikari Charana Bhatta bcbhatta14@gmail.com hodchemistry@cet.edu.in https://orcid.org/0000-0002-0630-9098 References [1]. Emsley, J. Nature’s building blocks: An A-Z guide to the elements; Oxford University Press: London, England, 2011. [2]. CRC handbook of chemistry and physics, Zirconium, 90th edition; Lide, D. R., Ed.; 90th ed.; CRC Press: Boca Raton, FL, 2009. [3]. Stwertka, A. A guide to the elements; 4th ed.; Oxford University Press: New York, NY, 2018. [4]. Nielsen, R. Zirconium and Zirconium Compounds. Ullmann’s Encyclopedia of Industrial Chemistry 2000. [5]. Lee, D. B. N.; Roberts, M.; Bluchel, C. G.; Odell, R. A. Zirconium: Biomedical and nephrological applications. ASAIO J. 2010, 56, 550– 556. [6]. Reddy, B. R.; Kumar, J. R.; Reddy, A. V. 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Ion Exch. 2005, 23, 345– 357. Copyright © 2022 by Authors. This work is published and licensed by Atlanta Publishing House LLC, Atlanta, GA, USA. The full terms of this license are available at http://www.eurjchem.com/index.php/eurjchem/pages/view/terms and incorporate the Creative Commons Attribution-Non Commercial (CC BY NC) (International, v4.0) License (http://creativecommons.org/licenses/by-nc/4.0). By accessing the work, you hereby accept the Terms. This is an open access article distributed under the terms and conditions of the CC BY NC License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited without any further permission from Atlanta Publishing House LLC (European Journal of Chemistry). No use, distribution or reproduction is permitted which does not comply with these terms. Permissions for commercial use of this work beyond the scope of the License (http://www.eurjchem.com/index.php/eurjchem/pages/view/terms) are administered by Atlanta Publishing House LLC (European Journal of Chemistry). mailto:amitsahoochemistry@gmail.com https://orcid.org/0000-0002-7480-658X mailto:jaykishon11@gmail.com https://orcid.org/0000-0002-2117-9711 mailto:bcbhatta14@gmail.com mailto:hodchemistry@cet.edu.in https://orcid.org/0000-0002-0630-9098 https://ijpcsonline.com/%20files/files/36-116.pdf https://ijpcsonline.com/%20files/files/36-116.pdf http://www.eurjchem.com/index.php/eurjchem/pages/view/terms http://creativecommons.org/licenses/by-nc/4.0 http://www.eurjchem.com/index.php/eurjchem/pages/view/terms 1. Introduction 2. Experimental 2.1. Reagents 2.2. Process 3. Results and discussion 3.1. Effect of acid concentration 3.2. Effect of extractant concentration 3.3. Effect of chloride ion concentration 3.4. Effect of temperature 3.5. Effect of metal ion concentration 3.6. Effect of diluent 3.7. Effect of pH 3.8. Stripping 3.9. Extraction equilibrium 4. Conclusions Acknowledgement Disclosure statement CRediT authorship contribution statement ORCID and Email References PrintField10: PrintField11: PrintField12: PrintField13: PrintField14: PrintField15: PrintField20: PrintField21: PrintField22: PrintField23: PrintField24: PrintField25: