Kerosene Extraction Research Articles

A closed-loop coupling process of leaching and solvent extraction for Li2CO3 and FePO4 recovery from spent LiFePO4

To satisfy the increasing global demand for the strategic metal lithium, recycling of LiFePO4 (LFP) batteries has become an irresistible trend and poses a challenge due to the cost. A low-cost process of recovering Li and FePO4 from simulated spent LFP was investigated through a closed-loop coupling technology of isomorphic substitution leaching and solvent extraction. A total of 99.41% of Li+ can be leached, and 96% of FePO4 can be recovered with an Fe2(SO4)3:LFP molar ratio of 1:6, H2SO4:LFP molar ratio of 0.5:1, and 0.4 ml H2O2/gLFP for 30 min. An eleven-stage extraction process for Fe3+ removal from lixivium-containing extraction, stripping and regeneration processes was designed and optimized. The total removal efficiency of Fe3+ was 97.22% by the 40 vt% N235 + 15 vt% TBP + kerosene extraction system at a phase ratio O/A of 3.5/1, and the lithium concentration in raffinate was 10.074 g·L−1. The closed-coupling process was carried out on the simulated spent LFP with a total Li recovery efficiency of >99%. The low-cost leaching agent Fe2(SO4)3 was cyclically utilized. The coupling process can not only serve as a promising efficient recycling method for spent LFP batteries but also supply an inspiring route for other expensive metal recycling.

Lithium Separation and Up-concentration from Battery Recycling Effluent by Synergistic Solvent Extraction

Exponential growth in the electric vehicle (EV) market warrants a stable supply of certain materials including lithium (Li). Due to its criticality and environmental concern, Li recycling from spent batteries is justified. Although there are several industrially established schemes for end-of-life battery recycling, major drawbacks are still encountered regarding Li recovery. In most recycling schemes, Li stands to be the last element that is recovered. This causes major loss of Li during the process and high energy is consumed to recover it from the final effluent i.e. evaporation, rendering Li recovery economically unattractive. Evaporation is generally applied to up-concentrate Li in the effluent to attain the minimum concentration required to induce precipitation and crystallization in Li salt production. In this research, solvent extraction is being proposed as a low energy alternative in Li up-concentration and separation from recycling effluent. The synergistic effect between 2-thenoyl trifluoro acetone (HTTA) and trioctylphosphine oxide (TOPO) as extractants in kerosene as diluent has been tested in batch studies to increase Li concentration in the final solution. Optimal extraction conditions reported include HTTA/TOPO mol ratio 1, shaking speed 250 rpm, extraction time 10 min, aqueous/organic volume ratio 1 and pH 10.1 (Li extraction rate 55.6 %). The maximum loading capacity of organic phase for Li was 1.2 g/L and complete stripping of Li could be achieved using 0.5 M sulfuric acid. It was demonstrated that the solvent extraction scheme can increase Li concentration in the effluent from 0.23 g/L to 10.06 g/L, which is suitable concentration for Li salt production by further precipitation or crystallization.

Closed-loop recovery of molybdenum and value-added reuse of tungsten from alloy waste in additive manufacturing

As metal additive manufacturing (MAM) technology is booming in the aerospace sector, alternatives to the traditional production methods of metals such as mining, processing, and refining with severe emissions are urgently needed. This study proposed a closed-loop route for efficient recovery of molybdenum (Mo) and value-added reuse of tungsten (W) from Cr–Co–Ni–Mo–W alloy waste in MAM. The results showed that the leaching efficiency of Mo and W reached 99.3% and 99.9%, respectively, using the dual chemical-physical means of mixed-alkali roasting and leaching by microwave heating, while the discharge of waste liquor containing Cr6+ was reduced. Leaching kinetic studies revealed that the metal leaching process was controlled by chemical reaction mechanism. Moreover, the 10%N1923 (primary amine)–5%TRPO (tri-alkyl phosphine oxide)–kerosene extraction system exhibited a synergistic extraction effect on Mo and W. After purification, Mo was recovered as Mo powder for MAM. Simultaneously, the recovered product of W, MnWO4, was applied as a photocatalytic material with excellent degradation of methylene blue dye. Ultimately, the proposed method obtained recovery efficiencies of 98.4% and 99.3% for Mo and W, respectively, achieving efficient and environmentally-friendly reuse of these key metals.

Selective extraction of lithium from high magnesium/lithium ratio brines with a TBP–FeCl3–P204–kerosene extraction system

The tributyl phosphate (TBP)–FeCl3–kerosene system is a common tool for lithium extraction from salt lakes. This system has two main problems. One, FeCl4− is unstable, which decreases the lithium extraction efficiency. Two, TBP readily degrades after long-term contact with high concentrations of acids and bases. Accordingly, the present authors introduce di(2-ethylhexyl) phosphate (P204) in conjunction with Fe3+ to construct a TBP–FeCl3–P204–kerosene extraction system. The optimal operating conditions were 10% P204 + 40% TBP + kerosene, an Fe3+/Li+ molar ratio of 1.6, and organic-to-acid phase ratio R(O/A) = 1. The final lithium ion single-stage extraction yield was 52.71%. The former washed 90.64% of Mg2+ when R(O/A) = 70, the latter washed 95.37% of Mg2+ when R(O/A) = 20. Using water as the stripping agent, the Li+ stripping efficiency decreased with increasing R(O/A). Ultraviolet and Raman spectroscopy indicated that TBP underwent complexation with Li+ and FeCl4−, whereas P204 underwent complexation with Fe3+ only. When the Cl− concentration was low, Fe3+ underwent complexation with P204 and was retained in the organic phase; whereas when the Cl− concentration was high, FeCl4− formed again in a manner that facilitated co-extraction with Li+ by TBP.

Solvent extraction of lithium from hydrochloric acid leaching solution of high-alumina coal fly ash

The present work used solvent extraction method to extract lithium from hydrochloric acid leaching solution of high-alumina coal fly ash. In extraction stage, the optimum conditions were explored, at 20 ℃ and O/A = 1:4, using 70%(Vol.) tributyl phosphate-30%(Vol.) sulfonated kerosene-0.36 mol/L Fe3+ as extractant, extraction of lithium could reach 99% by two-stage extraction. In scrubbing stage, 95% of Al3+ in loaded organic phase was scrubbed with 6 mol/L HCl at O/A = 40:1, then 97% of Ca2+ in the loaded organic phase was scrubbed by three-stage countercurrent scrubbing with 5.5 mol/L LiCl + 0.5 mol/L HCl at O/A = 30:1. In stripping stage, 99% of Li+ in scrubbed organic phase was stripped by five-stage countercurrent stripping with 6 mol/L HCl at O/A = 10:1. In regeneration stage, 2 mol/L NaOH was used as regenerant to remove free acid and exchange H+ of extractive compound. There were no third phase, emulsification and solid deposition during the whole experiment. The structure of extractive compound was determined by slope method, and extracted complex ratio of Li+, Fe3+, and TBP was 1:1:1. The extraction process was found to be exothermic and spontaneous by thermodynamic study.Therefore, it’s a promising method to recover lithium from hydrochloric acid leaching solution of high-alumina coal fly ash by TBP-FeCl3-sulfonated kerosene extraction system.

Establishing correlation between effective diffusivity coefficient and the mass transfer for Zn2+ column extraction by D2EHPA: An experimental and theoretical investigation

Mass transfer coefficient is an all-important parameter for the design of columns. This paper was aimed at analyzing mass transfer in the columns with counter-current flow. Considering that the available theoretical models have focused on the prediction of a single drop diffusion in nonionic systems and show poor agreement with the experimental data of an ionic or reactive extraction system, it is of interest to develop a new correlation for effective diffusion coefficient. In this regard, ZnSO4/D2EHPA (Zinc sulphate/Di(2-ethylhexyl) phosphoric acid)/Kerosene extraction system, involving chemical reaction, was investigated in spray and packed columns with counter-current flows. This proposed correlation was derived in the form of dimensionless parameters, in which the effects of operational parameters, e.g. dispersed phase flow rate, and packing height (for packed column) or nozzle inner diameter (for spray column), were taken into account. Interestingly, for the first time, the effect of temperature was explored and incorporated into the final correlation. The promising results of our model with R-square of ∼98% and 95% for spray and packed column respectively, suggest its applicability for the prediction of mass transfer coefficient in similar systems and, subsequently, improving the column design.

Leaching of metals with microemulsions containing bis-(2-ethyhexyl)phosphoric acid or tributylphosphate

The leaching of metals from oxide materials with sodium bis-(2-ethylhexyl)phosphate (NaDEHP) microemulsions containing extractants bis-(2-ethylhexyl)phosphoric acid (DEHPA) or tributylphosphate (TBP) was studied. It was shown that the microemulsions exist in a wide range of NaDEHP and water concentrations; the hydrodynamic diameter of microemulsion droplets was less than 10nm. Nanostructured fluids (extractant-containing microemulsions) provide the leaching of metals. It was shown on the example of copper recovery from CuO, the extraction into DEHPA- or TBP+CH3COOH-containing microemulsions took place; copper recovery into solutions of the extractants in kerosene was not observed. The leaching of copper, cobalt, nickel and iron from an oxidized cobalt-copper concentrate with DEHPA- and TBP+CH3COOH-containing microemulsions demonstrated low iron extraction in comparison with non-ferrous metals extraction. The DEHPA-containing microemulsion with concentration of the extractant CDEHPA=0.174mol/L demonstrated 72.1% of copper recovery for 5h of the leaching; at the same time recovery factors of Co, Ni and Fe were 6.0, 5.9% and 0.5%, respectively.

Extraction and separation of uranium(VI) and Fe(III) from lanthanide chlorides with N,N,N′,N′-tetrasubstituted alkyl diglycolamide extractants

It is of great significance to separate impure elements from rare earth in high purity rare earth production. The extraction of uranium(VI) with three structurally related N,N,N′,N′-tetrasubstituted alkyl diglycolamide extractants in kerosene was studied. The relationship between the chemical structure of diglycolamide and their uranium(VI) extraction behavior was discussed. The extraction of Fe(III) and Nd(III) from chloride media was compared with that of uranium(VI) under the same experimental conditions. The results showed that uranium(VI) and Fe(III) can be effectively removed from NdCl3 solutions with N,N,N′,N′-tetraoctyl diglycolamide using kerosene as diluent.

Solvent extraction of titanium from nitrate medium using some organophosphorus extractants

ABSTRACTThe extraction of Ti(IV) from nitric acid has been carried out using some organophosphorus extractants in kerosene. The Ti(IV) extraction in the investigated systems is endothermic. Oxalic acid was effective for stripping Ti(IV). The maximum loading of Ti(IV) was found to be 6.13 × 10−3, 6.175 × 10−3 and 5.005 × 10−3 M of Ti(IV) per mole extractant for CYANEX 925, 923 and 921, respectively, after five extraction stages. Kerosene is a more effective diluent for extraction of Ti(IV). FT-IR characterization and the separation of Ti(IV) are also discussed.

The removal of unburned carbon from fly ash by kerosene extraction

The recycling process was developed to remove and recover unburned carbon from fly ash using kerosene extraction. The effects of experimental factors such as shaking time, initial unburned carbon content, and organic to suspension (O/S) ratio on the removal of unburned carbon were investigated to obtain the optimum conditions. The results indicate that the removal ratio of unburned carbon increased with increasing shaking times and decreasing the initial unburned carbon content, but the residual amount of unburned carbon was independent of O/S ratio. The content of unburned carbon decreased successfully to less than 3% under the following conditions; 15 min in shaking time, 10% in pulp density, 30 °C in temperature, 200 rpm in shaking speed, and 0.5 in O/S ratio.

Solvent extraction of praseodymium(III) from acidic nitrate medium using Cyanex 921 and Cyanex 923 as extractants in kerosene

Solvent extraction of praseodymium(III) from acidic nitrate medium by the neutral organophosphorous extractants Cyanex 921 and Cyanex 923 in kerosene was studied. The effects of various parameters like equilibration time, nitric acid concentration, nitrate ion concentration, extractant concentration, temperature, and nature of diluents on the extraction behavior of Pr(III) were investigated. The extraction of 0.001 M Pr(III) was quantitative (93%) from the aqueous phase containing 0.001 M HNO_3 and 0.1 M KNO_3 using 0.5 M Cyanex 921/1 M Cyanex 923. On the basis of slope analysis, the compositions of the extracted species were formulated as Pr(NO_3)_3.2Cyanex 921 and Pr (NO_3)_3.Cyanex 923. The percentage of extraction of Pr(III) was found to decrease with increases in temperature. The standard enthalpy and entropy changes were negative owing to the complexation with decrease in randomness without a compensatory disruption of the hydration sphere of the metal ion. Mineral acids like hydrochloric acid (0.008 M) and sulfuric acid (0.03/0.02 M) were effective for the stripping of Pr(III) from the loaded organic phase with 0.5 M Cyanex 921/1 M Cyanex 923.

“The Black and Cruel Demon” and Its Transformations of Space:

“The Black and Cruel Demon” and Its Transformations of Space:

Comparison of liquid–liquid extraction of Cr(VI) from acidic and alkaline solutions by two different amine extractants

The extraction of hexavalent chromium, Cr(VI), was performed from acidic sulphate and alkaline carbonate media by using Aliquat 336 and Alamine 336 extractants in kerosene under different experimental conditions. The optimum conditions for extraction of Cr(VI) were evaluated by varying the experimental parameters. On the basis of the slope analysis data, the composition of the extracted species was found to be R 4 NHCr O 4 ¯ for Aliquat 336 and R 3 N H 2 Cr O 4 ¯ for Alamine 336 in acidic medium and ( R 4 N ) 2 Cr O 4 ¯ for Aliquat 336 in alkaline medium. The results of the effect of temperature on the equilibrium extraction constant value clarify that the extraction is an endothermic process for the extraction by Aliquat 336 and Alamine 336 in acidic and alkaline media. 1 M NaOH as strippant completely strip Cr(VI) from the loaded extractants from acidic medium, in one step. In alkaline medium good stripping of Cr(VI) can be achieved from loaded extractants using 1 M NaOH in two steps. The results indicate that extraction of Cr(VI) from acidic media is more favored than from alkaline solution. The liquid–liquid extraction method was applied for the removal and recovery of Cr(VI) from electroplating waste solution.

Modification of the commercial carrier in supported liquid membrane system to enhance lactic acid flux and to separate l, d-lactic acid enantiomers

Enhancement of lactic acid transmembrane flux through a supported liquid membrane system by using a modified carrier is first time demonstrated in this work. The results show that with the replacement of the chloride ion with a carbonate one in the commercial quaternary ammonium salt (Aliquat™ 336), the lactic acid fluxes are always higher at the correspondingly same volume ratio of extractants in kerosene. In addition, enhanced enantiomer separation of l, d-lactic acid mixtures is also achieved by adding β-cyclodextrin into the feed in the supported liquid membrane system. The separation factor is as high as 2.3 in both ideal and racemic mixture tests with an impressively high transmembrane flux.

Oil agglomeration of a lignite treated with microwave energy: Effect of particle size and bridging oil

Oil agglomeration of Sivas–Divriği (S–D) Uluçayır lignite fines was carried out using kerosene and kerosene–extract oil (which was obtained from lignite treated with microwave energy) mixture as a bridging oil. The effects of parameters such as the amount and type of bridging oil, microwave time and particle size on the agglomeration performance were investigated. The amount of kerosene was varied from 5 to 30 wt.% of the initial lignite loading. The values of the grade and recovery increased with an increase in the amount of kerosene added. Extract oil fraction of the lignite extract at various ratios in kerosene increased the agglomeration recovery from 95.88% to 98.55%. The effect of microwave time was investigated and it was found that the grade was also increased with increasing microwave time (4, 8 and 10 min). The grade of char (microwave time: 8 min) was increased in comparison with the original lignite while decreasing its recovery. Dense medium separations of the lignite were conducted and the results of their grade recovery performances were compared with those of agglomeration of the particles. During the inspection of particle size effect on the dense medium separation, the recovery was increased remarkably (from 12.07% to 89.50%) with increasing particle size, while decreasing the grade (from 0.732 to 0.697). In the oil agglomeration of lignite the recovery values were increased with increasing particle size.

Extraction of Carboxylic Acids by ABC Extractants: Effects of Temperature, the Polarity of the Diluent, and the Ratio Between Extractant Components

A study was conducted of the temperature effect on the extraction of lactic and malic acid by acid‐base couple (ABC) extractants in kerosene. Elevating the temperature from 30°C to 80°C decreases the extraction of both acids by ABC extractants comprising tricaprylyl amine (A336). The opposite effect is found for the extraction of lactic acid by primary amine‐containing ABC extractants. It seems that temperature effect in the extraction of lactic and malic acids by ABC extractants results, at least partially, from competition for H‐bonding. The study has also tested the effect of diluent polarity in ABC extractants by replacing kerosene there with octanol. It has shown that increased polarity affects the extraction of carboxylic acids mainly through stabilization of ion pairs and formation of H‐bonds. Another studied effect was that of the ratio between the amine and the lipophilic acid in the ABC extractants. The results were found to depend on the acid‐base properties, polarity, and structure of these components and on the properties of the extracted acid.

Separation of Am from lanthanides by a synergistic mixture of purified Cyanex 301 and TBP

The dependence of the distribution ratios of 241Am and lanthanides between purified Cyanex 301 (HBTMPDTP)–TBP–kerosene/nitrate solution on pH, lanthanide concentration in aqueous phase and degree of saponification of HBTMPDTP was investigated. The distribution ratios of 241Am and lanthanides increase with pH and degree of saponification of HBTMPDTP and decrease with lanthanides concentration. Countercurrent multistage extraction consisting of 7 extraction, 3 washing and 2 stripping stages showed that more than 99.99% of 241Am and less than 0.04% of lanthanides were extracted. The pH1/2 value of Am was 2.45 compared to 3.16 in case of HBTMPDTP–kerosene extraction.

Study of extraction and pyrolysis of Jordan tar sand

The extraction and pyrolysis of tar sand from Wadi Isal, Jordan have been investigated. Solvent type, mixing time, temperature, particle size and alkali concentration have been identified as important parameters for bitumen recovery. The results show that hot water extraction is ineffective since a small amount of bitumen has been obtained even at 80°C. Kerosene extraction shows a maximum bitumen recovery of about 43% at 80°C and 180–250 μm particle size. The kinetic parameters of pyrolysis have been determined based on first-order rate expression and their values were in agreement with other published data in the literature. Copyright © 1999 John Wiley & Sons, Ltd.

Solvent extraction of uranium(VI) from industrial and analytical grade phosphoric acid using organic extractants in kerosene with variable content of aromatic hydrocarbons

The distribution ratio of U(VI) between phosphoric acid, industrial and analytical grade, and kerosene solutions of D2EHPA-TOPO extractants with variable amount of aromatic hydrocarbons has been studied. Under these conditions it was observed that the content of aromatic hydrocarbons in the diluent as well as other ions present in industrial phosphoric acid play a significant role in the extraction of uranium(VI).

Polycaprolactone as a permanent plasticizer for poly(vinyl chloride)

AbstractPolycaprolactone at moderate usage levels has been determined to provide desirable modifications of both rigid and plasticized poly(vinyl chloride). In rigid PVC it effected significant improvement in melt processing as well as good modulus, tensile strength, and kerosene resistance. Impact strength was not measurably altered, but heat‐distortion temperature was appreciably lowered. In flexible PVC, polycaprolactone contributed increased tensile strength and ultimate elongation, reduced volatility, and kerosene extraction. Lowering of modulus and flex temperatures were similar to conventional liquid polymeric plasticizers, but melt processability was not as good as lower‐molecular‐weight plasticizers.