Removal Of Cobalt Ions Research Articles

Efficient removal of cobalt ions by capacitive deionization using an asymmetric electrode

Efficient removal of cobalt ions by capacitive deionization using an asymmetric electrode

Development and characterization of porous membranes based on PPSU/PES using polyethylene glycol as porogen: Application for cobalt removal by polyelectrolyte‐enhanced ultrafiltration

AbstractBACKGROUNDIn this work, a polyphenylsulfone/polyethersulfone (PPSU/PES) composite membrane was successfully prepared using the phase‐inversion method in the presence of polyethylene glycol (PEG) as a hydrophilic additive. The effect of concentration of PEG (0, 2, 4 and 6 wt%) was investigated by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and contact angle analysis.RESULTSThe obtained results confirmed that the morphology and hydrophilicity of the porous membrane varied with the addition of PES as reinforcing agent and the PEG concentration as porogen. SEM results confirmed that the membranes obtained have a high permeability with a finger‐shaped structure and that the size and density of the pores increase with an increase in the incorporated PEG. The contact angle was decreased and the porosity of the PPPn blend membranes was increased from 16.06 for the neat PPSU membrane to 385.3 L h−1 m−2 bar−1 for the PPP6 membrane. A strong interaction between the components (PPSU, PES and PEG) was revealed by FTIR spectroscopy and TGA.CONCLUSIONThe filtration results showed that PPP2 is the better formulation of the dope suspension in the range of ultrafiltration membranes in terms of flux (179.3 L h−1 m−2 bar−1) and bovine serum albumin retention (94%). The application of polyelectrolyte‐enhanced ultrafiltration using polyethylenimine (PEI) for the removal of cobalt ions afforded high removal rates (92.5%). The optimal performances were obtained at pH ≥ 4, transmembrane pressure of 4 bar and 1200 ppm of PEI. © 2023 Society of Chemical Industry (SCI).

Ultrasound assistance synthesis of optimized ion imprinted polymer for efficient and selective removal of cobalt ions from waste streams

Selective recognition of metal ions is a real challenge for a large range of applications especially in sorption purposes. The use of ultrasound in the synthesizing and modifying of sodium alginate-based material is investigated, for enhancing the dispersion, degassing, crosslinking processes and enhance the homogeneity of ion imprinted polymer properties. Cobalt imprinted polymer was prepared using an inexpensive and simple ultrasonic-mediated polymerization process that incorporated dual functional monomers, acrylic acid, and 2-Acrylamido-2-methylpropane sulfonic acid to feature a multifunctional of carboxylic and sulfonic groups. SEM, TGA, DTA, and EDX were used to analyze the surface morphology. FT-IR study confirmed that the complexation of the Co-IIP was successfully takes place. The ability of the adsorption of ion imprinted was optimized at pH 5. The increase of the temperature from 27 to 52 °C caused the increase in the adsorption capacity. Batch tests have been performed to evaluate the selectivity mechanism, and found that the prepared polymer exhibit excellent selectivity for Cobalt, more than nickel, and strontium at 300°K (single component) were 71, 20, and 12 mg.g−1 respectively. Pseudo-second-order kinetics and the Langmuir isotherm gave the most satisfactory explanation for the adsorption process. The prepared polymer can be reused 5 times with a very low loss in adsorption capacity. The prepared ion imprinted polymer is efficiently utilized in controlling Co2+ sorption/desorption processes, enabling its successful recovery from complex sample matrices for various applications especially that required separation processes.

Sulfonated Pentablock Copolymer with Graphene Oxide for Co2+ Ions Removal: Efficiency, Interaction Mechanisms and Secondary Reaction Products

In this work, sulfonated pentablock copolymer (s-PBC) and s-PBC mixed with graphene oxide (s-PBC_GO) layers were deposited on polypropylene (PP) fibrous filters and tested as active coatings for the removal of cobalt ions from water using adsorption and filtration processes. Some of the coated filters were treated by UV light irradiation to modify their hydrophilic properties. The filters were characterized, before and after the processes, by energy-dispersive X-ray (EDX) analysis and Fourier transform infrared spectroscopy (FT-IR). The Qt (mg/g) values, defined as the weight ratio between the removed ions and the coating layer, were evaluated. In the case of adsorption processes, the best results for the removal of Co2+ ions were achieved by the s-PBC_GO coating, with a Qt of 37 mg/g compared to 21 mg/g obtained by the s-PBC. This was ascribed to the presence of GO, which contains more favorable sites able to adsorb positive ions from the solution. Vice versa, for filtration processes, the s-PBC coated filters show similar or slightly better results than the s-PBC_GO coated ones. Such differences can be ascribed to the shorter contact time between the solution and the coating layer in the case of filtration, with respect to adsorption processes, thus reducing the chance for the ions to be adsorbed on the GO layers before passing through the filter. A collateral effect, observed in this study and enhanced in the case of UV-treated coatings, is the release of radical oxysulfur species. The mechanisms involved in this effect are discussed and identified as a consequence of the interaction between the coating layers and metal ions. In order to identify the mechanism of oxysulfur radicals formation and considering a water sample closer to real water, the Co2+ ions adsorption experiments were conducted in the presence of a competitive organic contaminant (i.e., methyl orange, MO).

Efficient adsorptive removal of Co2+ from aqueous solution using graphene oxide.

This study aimed to utilize synthesized graphene oxide (GO) for adsorptive removal of cobalt ions and investigate the adsorption mechanism using advanced techniques such as X-ray absorption spectra (XAFS). The GO was synthesized via an improved Hummers method, resulting in high surface area (93.7 m2/g) and abundant oxygen-containing functional groups. Various characterizations, including SEM, TEM, Raman, FT-IR, TG, potentiometric titrations, and N2 sorption-desorption measurements, were employed to characterize the GO. The adsorption behavior of GO towards Co2+ was investigated, and the results showed that the adsorption process followed a pseudo-second-order kinetic model and the Langmuir model, with a maximum sorption capacity of 93.7 mg/g. The adsorption process was chemisorption and endothermic, with GO showing adsorption selectivity order of Co2+ > Sr2+ > Cs+. Based on various characterizations such as X-ray absorption near-edge spectroscopy (XANES), extended X-ray absorption fine structure (EXAFS), FT-IR, and XPS, the sorption mechanism of Co2+ onto GO was discussed, with the results indicating that coordination and electrostatic interaction were the primary adsorption mechanisms, with oxygen-containing functional groups playing a vital role. The first coordinating atom for Co2+ was O, and the coordination environment was similar to that of cobalt acetate and CoO. Overall, this study provides comprehensive understanding of the adsorption behavior and mechanism of Co2+ onto GO, highlighting its potential as an effective adsorbent for removing nuclides from aqueous solution.

Efficiency evaluation of Falcaria vulgaris biomass in Co(II) uptake from aquatic environments: characteristics, kinetics and optimization of operational variables

In the present research, the seeds of Falcaria vulgaris were extracted from the investigated environment and used for crop cultivation. This study has focused on the efficiency evaluation of Falcaria vulgaris biomass (FVB) in cobalt ions removal from aqueous solutions. The biosorbent was characterized using FTIR, BET, EDAX-EDS, and SEM. The optimal conditions were determined by the response surface methodology (RSM) based on a Box-Behnken design (BBD) model. The BBD model had R 2 , R adj 2 and R pred 2 values of 0.9919, 0.9774, and 0.8929, respectively. The cobalt removal under different conditions of the BBD model varied from 36.14% to 82.11%. Based on the numerical optimization of the quadratic model, the maximum cobalt removal at a biosorbent-to-metal ratio of 10:1, pH = 4.88 and contact time of 70 min was calculated at 80.941%. The high accuracy of the model in predicting the optimal conditions for cobalt adsorption by FVB was confirmed using statistical analysis and validation tests. The adsorption process of FVB also follows a pseudo-second-order kinetic model, which suggests that the rate-controlling step in cobalt removal is the chemical interaction between functional groups in FVB and Co+2 ions. This study shows that FVB, a low-cost biosorbent, can be a suitable candidate for removing heavy metals such as cobalt from aqueous solutions.

The enhanced separation effect of synthesized hydroxyapatite incorporated with ethylenediamine-tetramethylene phosphonic acid for Zn2+ and Co2+ ions and the deep insight into mechanism

Hydroxyapatite (HAP) incorporated with ethylenediaminetetramethylene phosphonic acid (EDTMP) was prepared and used for the separation of the toxic Zn2+ and Co2+ heavy metal ions in an aqueous solution. When the doping amount of EDTMP was 20%, the adsorption capacity of 20ED-HAP composite for Zn2+ and Co2+ reached 229.5 mg/g and 162.4 mg/g, which was 11.0 times and 11.8 times that of synthesized HAP in the absence of EDTMP. The effects of different concentrations of common coexisting ions such as Na+, K+, Ca2+, and Mg2+ were explored, and the removal rate of Co2+ or Zn2+ in a simulated actual water environment was also investigated. The removal of cobalt ions by EDTMP-HAP complex included ion exchange and surface complexation mechanisms. In addition to the above two mechanisms, the separation of zinc ions involved the dissolution precipitation mechanism with the formation of CaZn2(PO4)2·2H2O. Moreover, the affinity between EDTMP and HAP was revealed via Independent Gradient Model based on the Hirshfeld partition of molecular density (IGMH) and Hirshfeld surface analysis. Meanwhile, the interaction mechanism between EDTMP and Co2+ or Zn2+ was explored in depth through Multiwfn wavefunction analysis. The prepared adsorbent could be used as a low-cost potential adsorbent for toxic Zn2+ and Co2+ ions.

Ultra-selective chelating membranes for recycling of cobalt from lithium-ion spent battery effluents by electrodialysis

The recovery of valuable resources from spent effluents is critical to ensure sustainable growth and reduce commodity shortages at global levels. Spent batteries are largely untapped resources containing multiple high-value metal ions that may be harnest and resued indefinitely to develop a circular battery economy. Challenges however lay with the cost of purification and recovery strategies and the limited selectivity of existing processes. This work presents the development of selective cation exchange membranes suitable for the selective recovery of cobalt from mixtures of lithium, cobalt, and nickel from spent battery effluents. Efficient cation exchange membranes were generated by modifying poly(vinyl chloride) films with ethylene diamine followed by grafting of 5-chloro-8-hydroxyquinoline (5C8Q) chelating agents and two synthesis routes were compared including surface and bulk grafting and the membrane separation properties were benchmarked against CIMS Neosepta. Besides being stable across a pH range between 2 and 8, relevant to spent battery lixiviat, the surface grafted membranes exhibited the lowest energy of sorption in comparison to bulk membranes, which was ten times lower than that of the commercial CIMS Neosepta reference membranes. The transfer of ions from model single salt solutions across the surface grafted membranes allowed for over 60 % of cobalt recovery within 1 h, while nickel and lithium were transferred only up to 18 % and 0.2 %, respectively. In addition, the electrodialysis-based separation of multi-component solutions remained very cost-effective with cobalt ion removal amounts up to 58 %, leading to Co/Li separation factors as high as 247. This novel chelating agent strategy opens avenues for the development of highly efficient and selective membrane materials, which are able to operate in extreme pH environments and supporting ultra-selective ionic transfer.

Removal of cobalt ions (II) from simulated radioactive effluent by electrosorption on potassium hydroxide modified activated carbon fiber felt

In this study, the electrosorption property of potassium hydroxide modified activated carbon fiber felt (ACFF-KOH) to Co2+ in simulated radioactive effluent was evaluated. Factors influencing the electrosorption such as applied voltage, initial concentration, pH, cyclic flow rate, competitive ions and cycle numbers on Co2+ removal rate were investigated. Kinetic models and isotherm models were used to evaluate the electrosorption performance of ACFF-KOH. The results showed that the voltage enhanced the removal capacity of Co2+, which raised from 5.92 to 14.80 mg·g−1 when the applied voltage increased from 0 to 1.6 V. Higher initial concentration of the solution induced larger electrosorption capacity. In addition, the optimal adsorption pH of the electrosorption was around 5. When competing ions exist, the removal rate of Co2+ decreased. Furthermore, ACFF-KOH had excellent cycling performance, and the removal rate remained above 85 % after 6 cycles. The pseudo-first-order (PFO) model fitted the data better than the pseudo-second-order (PSO) model, indicating that physisorption was the rate-limiting step during the eletrosorption process. As the Langmuir isotherm had a higher regression coefficient (0.9983) than the Freundlich isotherm, monolayer adsorption was the main adsorption mechanism for Co2+ on the ACFF-KOH electrode. The BET results showed that KOH modification improved the pore parameters of ACFF. According to the XPS and XRD results, Co(OH)2 precipitates were generated on the electrode surface after electrosorption. The above results indicated that ACFF-KOH had excellent electrosorption and regeneration performance for Co2+ in aqueous solution, thus it has great application value in the treatment of cobalt-containing radioactive effluent.

Green Synthesis Ca-MgO Nanosorbent for the Uptake of Cobalt Ions from Aqueous Media

Ca-doped magnesium oxide nanosorbent has been prepared by sol-gel in the presence of gum arabic extract and assessed for the removal of cobalt ions (Co (II)) from aqueous media. X-ray diffraction analysis indicates the formation of MgO and CaO composites with a mean crystallite size of 6 nm having a large surface area of 50 m2/g. Scanning and transmission electron microscopy observations reveal spherical-shaped particles at the nanoscale around 20 nm. Besides, X-ray photoelectron spectroscopy and Fourier transform infrared analyses manifest the existence of functional groups, which will facilitate the adsorption of metal ions. The adsorption capability of the CaO-MgO nanosorbent achieved 469.5 mg/g for Co (II) ions under optimum operating conditions. Furthermore, the experimental data elucidate that the adsorption process is primarily diffusion-based and that both intraparticle and boundary layer diffusion appear to play a key role in the rate-controlling step. The findings of this study highlight the remediation of contaminated water by cobalt ions by CaO-MgO nanostructure and can be extended to other metal ions and organic pollutants.

Cobalt ion removal using magnetic biochar obtained from conocarpus erectus leaves

Cobalt ion removal using magnetic biochar obtained from conocarpus erectus leaves

Production of hydroxyapatite‐based adsorbent for the removal of cobalt ions from the aqueous solution

AbstractThe aim of the current study was to recover and separate cobalt ions from multielement solution, using hydroxyapatite (HAp) and magnetic nanocomposite of HAp/Fe3O4 as adsorbents. Cobalt ion adsorption process was conducted batchwise within the temperature 25˗55°C, exposure duration 5˗120 min by applying a dose of 0.25–5 g/L as the adsorbent at pH 2 to 9. Adsorbent characterization was performed using advanced spectroscopic techniques such as Fourier Transform Infrared Spectroscopy, Scanning electron microscopy, and Energy‐dispersive X‐ray spectroscopy. The maximum ionic adsorption efficiency using HAp was 90.48% against 94.72% in the case of the magnetic nanocomposite of HAp, under optimal conditions. Various isotherm models were used to evaluate the adsorption capacity and equilibrium coefficients for adsorption of the cobalt ions by the prepared adsorbents. The isotherm models data showed that the adsorption process is desirable by the adsorbents and by adding nanoparticles of Fe3O4 the adsorption capacity improves.

Removal of Cobalt Ion in Aqueous Solution Using Zeolitic Materials Synthesized from Jeju Volcanic Rocks

Removal of Cobalt Ion in Aqueous Solution Using Zeolitic Materials Synthesized from Jeju Volcanic Rocks

Fabrication and optimization of poly(ortho-aminophenol) doped glycerol for efficient removal of cobalt ion from wastewater

Remediation of water pollution has been a crucial step in the environmental engineering processes. In the past decades, the adsorption technique was commonly used for the removal of heavy metals in water. Owing to the unique properties of polymer-based composites, a new nanocomposite, poly-ortho aminophenol and glycerol (P(oAP)/G), has attracted great attention in this field. Different parameters were studied to optimize the preparation of P(oAP)/G such as temperature, reaction time, and the concentration of monomer and initiator. As well as the structure of P(oAP)/G and chemical characterization was examined using various modalities. The fabricated nanocomposite had an urchin-like the shape of 3–5 μm in diameter, 16–18 nm in thickness of dendritic fibers, and a high surface area of 77.13 m2/g as well.Interestingly, the P(oAP)/G efficiency for Co2+ ions removal reached 96%, with an adsorption capacity of 117.9 mg/g, suggesting a higher capacity for water treatment. Further, cobalt ion adsorption followed the pseudo-second kinetic model and Temkin isotherm model. One can summarize that the P(oAP)/G is a good candidate for adsorption of metal ions which can be further studied on a large experimental scale in water purification processes.

Safe isolation and storage of simulated radioactive waste contains cesium and cobalt ions by magnetic natural-based nanocomposites

Radioactive waste is hazardous to most forms of life. For this purpose, magnetic gum acacia/polyacrylamide/graphene (GA/PAAm/GR)-MNC and magnetic gum acacia/polyacrylamide/silica (GA/PAAm/ SiO2)-MNC nanocomposites of different formulation were prepared by gamma irradiation. The nanocomposites were used as adsorbents for cesium and cobalt ions removal from their wastes as a simulation of radioactive wastes. It was found that the maximum adsorption of Cs+ occurs at pH-7 and for Co2+ it can be obtained at pH-5. The highest removal toward Cs+ by (GA/PAAm/GR)-MNC and (GA/PAAm/SiO2)-MNC was done at 0.3 and 0.5 wt% for GR and SiO2, respectively, while the nanocomposites contain 0.1 wt% GR and 0.3 wt% SiO2 have the highest removal of Co2+. The uptake capacity of Co2+ increases with increasing the initial Co2+ concentration, while it has a maximum value for Cs+ at 75 mg/L. The removal ability of the nanocomposites toward Co2+ is higher than Cs+. It depends on the nature of interaction with the functional groups. The presence of K+ adversely affects the adsorption of Cs+. Co2+ removal highly decreases in the presence of Mg2+. The equilibrium contact time for adsorption of Cs+ and Co2+ is 220 and 120 min, respectively. The removal percentage increases with temperature indicated that the adsorption reaction is endothermic except for Cs+ by (GA/PAAm/GR)-MNC. Cs+ and Co2+ are hardly eluted from the nanocomposites as immersed in different media; water, 0.1M NaOH, and 0.1M HCl.

Utilization of Nanocrystalline Cellulose for Adsorption of Divalent Cobalt Ions in the Aqueous Phase

Nanocrystalline cellulose (NC) is a cellulose derivative product that has attracted a lot of attention because of its versatile applications, one of which is in adsorption. In this study, NC was prepared through H2SO4-hydrolysis of filter paper. Several physical characterizations were employed to confirm the formation of the NC nanoparticles, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, and Fourier transform infrared spectroscopy (FTIR). The nano-rod-shaped NC particles, with an average particle length of 255 nm, were observed from the electron micrographs. The resemblance characteristic of NC with cellulose was demonstrated from the occurrence of XRD peaks at (110) and (200) lattice plane. The FTIR bands’ spectra of the NC are similar to that of the reported literature. The NC was utilized as the adsorbent for the removal of cobalt ions in the synthetic solution. The effect of pH on the removal of cobalt ions by NC was evaluated by employing potentiometric titration. It was revealed that the complexation between the two compounds occurs greater at a pH of 6.6. The adsorption isotherm of cobalt ions was investigated at three different temperatures of 30, 45, and 60°C. The adsorption isotherm was found to be well fitted with the Langmuir model, with the maximum adsorption capacity of 47.53 mg g-1 at 30°C. The adsorption capacity was found to decline as the temperature increased, where the maximum adsorption capacity was 44.62 ± 2.32 and 40.56 ± 2.03 mg g-1 at 45 and 60°C, respectively. The adsorption of cobalt ions on NC shows the exothermic adsorption behavior.

Synthesis, characterization and application of mesoporous silica in removal of cobalt ions from contaminated water

Mesoporous silica was synthesized by a chemical precipitation process and its efficiency was investigated for removal of cobalt ions (Co2+) from the contaminated water in a laboratory scale. The characteristic of the synthesized mesoporous were analyzed by SEM image. Optimal conditions were determined for important parameters such as solution pH, the absorbent dose, the initial Co2+ concentration and contact time by a one-variable method through the batch experiments. The SEM results confirmed the synthesized silica had high porosity with a honeycomb-like structure. The results showed that increase the adsorbent dose and contact time to the optimum increased the efficiency of Co2+ adsorption. However, with increasing the concentration of Co2+, the removal efficiency was decreased. The removal of Co2+ was 85% at the optimal contact time of 8 h. The maximum adsorption efficiency was 89% at pH = 7, initial Co2+ concentration of 5 ppm, and the adsorbent dose of 0.3 g/50 ml. The study of adsorption isotherm and kinetic models indicated that the adsorption process followed the Freundlich isotherm (R2 = 0.9359) and the second-order kinetic model (R2 = 0.9995). The synthesized mesoporous silica presented a chemical adsorption mechanism for Co2+ removal from aqueous media and it can be used in wastewater treatment containing bivalent heavy metals such as Co2+.

Kinetic, equilibrium, and thermodynamic studies for adsorptive removal of cobalt ions by rice husk from aqueous solution

Kinetic, equilibrium, and thermodynamic studies for adsorptive removal of cobalt ions by rice husk from aqueous solution

Immobilization of cobalt ions using hierarchically porous 4A zeolite-based carbon composites: Ion-exchange and solidification

The efficacy of the synthesized 4A zeolite and the 4A zeolite-based carbon composites were examined for the removal of cobalt ions from an aqueous solution by ion-exchange. Two types of agricultural waste were chosen as precursors to prepare the porous supports for composites synthesized at hydrothermal conditions. The maximum exchange capacity of zeolite portions present in 4A zeolite/Almond shells carbon (AAS) and 4A zeolite/Walnut shells carbon (AWS) reached to 235.175 and 202.887 mg ion/g zeolite; but it reached to 99.525 mg ion/g zeolite for 4A zeolite (A) at same conditions. Removal of cobalt ions by ion-exchange process enhanced when the temperature and pH of the cobalt solution increased. The equilibrium data are precisely fitted by the Freundlich model with a correlation factor (R2) of 0.9807, 0.9859 and 0.9857 for A, AAS and AWS. The cobalt uptake by zeolite-based carbon composites process is controlled by ion-exchange. The Weber and Morris intra-particle diffusion kinetics and Boyd model equations confirmed enhancement of cobalt removal using the composites. The seepage of cobalt ions from the solidified ion-exchangers encapsulating ions reduced to 0.01 ppm in H2O and to 0.05-0.25 ppm in 0.5 N NaCl solution.

Electro-enhanced removal of cobalt ions from aqueous solution by capacitive deionization

Electro-enhanced removal of cobalt (Co) ions from aqueous solution by capacitive deionization (CDI) was investigated in this study. The effect of applied voltage and initial Co ions concentration, as well as coexisted ions on removal efficiency of Co ions was determined. Co ions adsorption performance was also evaluated by kinetic models, isotherm models and three mass transfer models. The results indicated that the removal efficiency of Co ions had positive correlation with applied voltage (R2 = 0.9991), which increased from 15.11% to 36.54% when the applied voltage increased from 0 V to 1.2 V. However, the removal efficiency of Co ions decreased gradually from 36.54% to 9.51% with the increasing initial Co ions concentration from 5 to 30 mg L−1. The coexisted ions (Sr and Cs) also largely inhibited the removal efficiency of Co ions and make it reduce to 8.37%. After fitting the adsorption data, pseudo-second order (PSO) model was better than pseudo-first order (PFO) for each applied voltage and initial concentration. A monolayer adsorption is the main adsorption mechanism of Co ions adsorption on the activated carbon cloth (ACC) because of the higher regression coefficient (0.964) by Langmuir isotherm. Based on kinetics together with the equilibrium isotherm, three mass transfer models were established and adsorption of the ions onto the active sites (AAS) model is the rate-limiting step due to the best fitting for the kinetic adsorption data of Co ions on ACC electrode. In addition, the Co ions were uniformly distributed on ACC electrode after adsorption.