Ion Flotation Research Articles

Removal of Zn Ions from Synthetic Wastewater Using Graphene Oxide as a Nanocollector in Ion Flotation

Removal of Zn Ions from Synthetic Wastewater Using Graphene Oxide as a Nanocollector in Ion Flotation

The Review of Treatment of Copper Ion in Wastewater and Comparison Between Four Treatment

This paper presents a comprehensive review of various methods used to remove copper ions from wastewater, highlighting their efficiency and feasibility. The main focus is on adsorption, ion flotation, membrane-based techniques, and electrochemical cells, with a particular emphasis on innovative approaches like the use of graphene oxide electrodes. The comparison and analysis section assesses each method’s removal efficiency, operational challenges, and costs, providing a critical perspective on their practical application in industrial settings.

Selective removal of Gallium from mixed metal solutions with Arsenic by ion flotation using the biosurfactant rhamnolipid

Rhamnolipids have received great attention in various environmental applications in terms of metal complexation and recovery. However, the effect of metal ions on interfacial and foaming properties in relation to flotation are not much studied. To assist, this study investigated the effect of metal ions alone and in a mixed metal system containing Gallium (Ga) and Arsenic (As) on these properties of rhamnolipid, along with isothermal titration calorimetry to study rhamnolipid-metal interactions. Further, the potential of rhamnolipid to recover and separate Ga from As was assessed using bioionflotation. Ga alone and in mixed metal system had a remarkable effect on the interfacial and foaming properties of rhamnolipid as compared to As alone. The effect of operating parameters like pH, rhamnolipid concentration, and airflow rate had a significant influence on the separation performance. Nearly 74% Ga was removed at 0.85 mM rhamnolipid concentration, pH 6, and an airflow rate of 80 ml/min. The selectivity index of Ga over As was highest (17.2) at 0.85 mM rhamnolipid concentration, pH 6, and an airflow rate of 40 ml/min. Also, the selective separation of Ga was dependent on the recovery of water from the foam. Altogether, the results provide new insights on the interfacial and foaming properties of rhamnolipid and its efficiency as an ion collector for Ga and showed that the optimized process parameters could be expected to provide very efficient separation and recovery of target metal via ion flotation.

Flotation of Chromium Ions from Simulated Wastewater Using Air Microbubbles

A microbubble air flotation technique was used to remove chromium ions from simulated wastewater (e.g. water used for electroplating, textiles, paints and pigments, and tanning leather). Experimental parameters were investigated to analyze the flotation process and determine the removal efficiency. These parameters included the location of the sampling port from the bottom of the column, where the diffuser is located to the top of flotation column (30, 60, and 90 cm), the type of surfactant (anionic, SDS, or cationic, CTAB) and its concentration (5, 10, 15, and 20 mg/L), the pH of the initial solution (3, 5, 7, 9, and 11), the initial contaminant concentration (10, 20, 30, and 40 mg/L), the gas flow rate (0.1, 0.2, 0.3, and 0.5 L/min), and the contact time (5, 10, 15, 20, 25, 30, and 35 min). The experimental results revealed that the highest removal efficiency (95%) was achieved in 20 min with a pH of 7, a flow rate of air 0.5 L/min, an SDS surfactant concentration of 15 mg/L, and a pollutant concentration of 30 mg/L at a sampling port height of 30 cm. The use of microbubbles in comparison to normal bubbles, resulted in a 56% improvement of the removal efficiency. The flotation process follows a first-order kinetics.

A review of the application of nanoparticles as collectors in ion flotation

Ion flotation is one of the most promising and unique methods for reducing or removing toxic heavy metal ions, organic pollutants, or inorganic anions and cations from mining and metallurgical wastewaters. It is a cost-effective and convenient method. In ion flotation, surface-active ions are removed from aqueous solutions by adding surfactants. Therefore, the main purpose of this review article was to summarize the application of various surfactants (nanoparticle surfactants, chemical synthetic surfactants and biosurfactants) used in ion flotation. Then, the advantages, disadvantages, and prospects of surfactants were comprehensively discussed. Recent progress regarding nanoparticle surfactants in ion flotation and the mechanism of colligends binding with nanoparticles were evaluated.

Gallium bioionflotation using rhamnolipid: Influence of frother addition and foam properties

The current study investigated the application of rhamnolipid biosurfactant as an ion collector in bioionflotation. In a top-down approach, the influence of rhamnolipid on gallium (Ga) ion flotation and recovery were investigated followed by detailed studies on the influencing parameters and foam characterization. Rhamnolipid exhibits extensive foaming properties and foam produced by rhamnolipid alone has higher stability making it difficult to collect the flotation concentrates. An addition of 1,2-decanediol introduces instability to this foam and also aids in concentrate collection. Observations during the flotation studies resulted in a series of investigations on rhamnolipid properties such as aggregate size, surface tension, and foam characterization. These results indicated that the addition of Ga and/or 1,2-decanediol affected the molecular aggregation of rhamnolipid. Moreover, the surface activity, foamability, foam drainage, and foam coarsening/coalescence of the rhamnolipid changed in the presence of Ga and/or 1,2-decanediol. In a batch bioionflotation process, rhamnolipid was able to remove nearly 80% Ga at pH 7 in presence of 1,2-decanediol. However, upgrading was higher at pH 6 without 1,2-decanediol, which is important when considering the flotation recovery in presence of other metals. Such biosurfactants have a high potential for wide applications in ion flotation and further optimization of flotation parameters is essential.

Toxic heavy metal ions removal from wastewater by ion flotation using a nano collector

Industrial wastewater treatment containing heavy metal ions has been a challenge in the ion flotation process development in recent years due to the high collector consumption required to achieve maximum ion removal. To address this issue, a nano collector consisting of functionalized graphene oxide (FGO) was synthesized and applied to increase the removal of heavy metal ions (lead, copper, nickel, cadmium, and zinc) from wastewater. This study evaluated the effect of various critical operating conditions including pH, collector/frother type and concentration, gas type, gas flowrate, and energy input on ion flotation performance to improve the efficiency of the process in this investigation. It was found that using FGO not only increased the ion removal percentage but also decreased collector consumption and water recovery, all of which improved the ion flotation process performance. Under the optimum chemical and hydrodynamic conditions using FGO with much lower concentration than stoichiometry concentration resulted in the maximum removal of lead, copper, nickel, cadmium, and zinc ions with percentages of 97.07, 99.02, 98.38, 95.20, and 98.94, respectively. In optimum condition, water recovery was 8 %. The use of FGO in the ion flotation process for wastewater treatment offered significant benefits, including high adsorption efficiency, low collector consumption, recyclability, and the absence of critical micelle concentration (CMC) and frothing properties.

Rare Earth Elements Recovery from Primary and Secondary Resources Using Flotation: A Systematic Review

Rare earth minerals (REMs) contain rare earth elements (REEs) that are important in modern technologies due to their unique magnetic, phosphorescent, and catalytic properties. However, REMs are not only non-renewable resources but also non-uniformly distributed on the Earth’s crust, so the processing of REE-bearing secondary resources via recycling is one potential route to ensure the long-term sustainability of REE supply. Flotation—a method that separates materials based on differences in their surface wettability—is a process applied for both mineral processing and recycling of REEs, especially when the particles are fine and/or a high-purity product is required. In this review, studies about rare earth flotation from 2012 to 2021 were systematically reviewed using the PRISMA guideline. It was found that most REM flotation research works focused on finding better collectors and depressants while, for recycling, studies on advanced flotation techniques like froth flotation, ion flotation, solvent sublation, electroflotation, and adsorbing colloid flotation with an emphasis on the recovery of dissolved REEs from aqueous solutions dominated.

Superchaotropic ion flotation: A new concept for the extraction and separation of nanometer-sized ions by non-ionic surfactant-based foams

Ion flotation is a separation technology for recovering ions from dilute aqueous solutions. All ion flotation processes known so far make use of ionic foaming agents (surfactants) to selectively extract ions of opposite charge by electrostatic interactions. Recently, it was shown that nanometric-sized ions (nano-ions) with low charge density, such as certain polyoxometalates (POMs), strongly adsorb to neutral hydrated surfaces. In this study, we provide proof-of-concept for a method that we call “superchaotropic ion flotation,” which uses non-ionic surfactant foams to selectively recover and separate superchaotropic POMs from other ions, including non-superchaotropic ions. Specifically, we investigated the extraction of isopolyoxomolybdates, formed by pH and concentration variation of molybdate aqueous solutions, using foams produced with a commercial polyethoxylated surfactant (BrijO10). The speciation of polyoxomolybdates was investigated by Raman spectroscopy and small angle X-ray scattering (SAXS). SAXS has also confirmed the superchaotropic behaviour of the polyoxomolybdates species via the characterization of their strong adsorption on surfactant micelles. The flotation recovering is high and maximal at pH 1, a pH for which Mo36O1128−, an anion with a low charge density, is the predominant molybdate species. It was found that the surfactant has a strong influence on the molybdate speciation. It was also demonstrated that molybdate may be separated from tungstate at pH 2 by superchaotropic ion flotation. In conclusion, we propose a novel ion separation method via non-ionic surfactant aqueous foams and we show that the superchaotropic effect makes it possible to foresee various applications in separation science.

Silver(I) Recovery by Ion Flotation Process from Aqueous Solutions in Cells with Spargers

Extractive metallurgy has recently turned its attention to waste treatment for the recovery of precious metals through innovative metallurgical processes, such as ion flotation. This work studied the influence of several chemical and physical factors, such as the concentration of xanthate [x], frother agent [e], dithiophosphate [xl], pH, superficial gas velocity Jg, percentage of gas holdup Eg, bubble diameter (Db) calculated with the drift flux model, and the type of sparger, in the efficiency of silver(I) recovery by the ion flotation technique in sub-aerated cells. The results obtained indicate a 90.7% v/v recovery of silver(I) under conditions of 3.77 × 10−4 M [x], 1.25 × 10−4 M [e], Jg 0.5 cm/s, Jl 0.19 cm/s, Eg of 4.1% v/v, and Optimal Db of 0.11 cm, with a rigid bubble generator, achieving an apparent flotation kinetics of 4.16 1/min. The use of combinations [x]–[xl] achieve a silver(I) recovery of 86.9% with a Jg of 1.0 cm/s. The best recovery efficiencies achieved 93% w/w silver(I) are with pH 8.0, [e] of 1.25 × 10−4, Jl of 0.19 (cm/s) and a rigid sparger compared to a flexible one.

The ion flotation of copper, nickel, and cobalt using the biosurfactant surfactin

Heavy metal contaminated waters are a significant environmental hazard, which require novel treatment methodologies. Further, the metals which might be recovered from these streams have significant intrinsic value, if they can be collected and concentrated. This work demonstrates, for the first time, the use of surfactin, an environmentally benign biosurfactant, for the flotation of metal ions (Cu2+, Ni2+, and Co2+). Surfactin, at a molar ratio of 1:3, has been shown to float 75.2%, 94.7%, and 98.2% of initial 100 mu M solutions of copper nickel and cobalt, respectively. Increasing the gas flow rate modifies the float by increasing the carryover of water into the overflow. A pH of 5 was found to be ineffective (due to surfactin precipitation), while a pH of 10 was less effective than pH 7, likely due to the ionic speciation of the metals in solution tending to hydroxyl precipitates at a high pH. This work demonstrates an opportunity for the recovery of metals (at low concentrations) using biosurfactant-based froth flotation.

Removal of hazardous ions from aqueous solutions: Current methods, with a focus on green ion flotation.

Hazardous ions, like those of heavy metals, cause significant health and environmental problems when they are discharged into water resources naturally or through various industrial processes. Removing these ions from water is of significant importance in the provision of high-quality water for drinking and agricultural usage. This work discusses current techniques that are frequently used for the removal of heavy-metal ions from aqueous solutions by absorption, particularly the use of biodegradable surfactants in ion flotation. Certain new surfactants promise high efficiency in their use in the ion-flotation process and in their application in industrial-water treatment to remove heavy metals. As an example, this work demonstrates the high efficiency of surfactants based on an amino-acid (L-cysteine) in removing a range of heavy-metal ions in a simple, single-stage ion-flotation process. High foaming ability, the ability to operate in various temperatures and pHs, decomposing into natural products and high binding affinity for heavy-metal ions make the cysteine-based surfactants a highly suitable compound to replace current commercial surfactants in ion- and froth-flotation processes. Removal of particular ions can also be achieved in ion flotation; a suitable choice of parameters, such as pH and surfactant concentration, favours the surfactant binding to those ions. Further intensive work is required to develop an optimal process to recover valuable elements from waste solutions.

Ion flotation and its applications on concentration, recovery, and removal of metal ions from solutions

Ion flotation and its applications on concentration, recovery, and removal of metal ions from solutions

Development of technology for extracting metals from process solutions by ion flotation

The article shows the possibility of complex extraction of metals from metalcontaining solutions-wastes of non-ferrous metal production, which is one of the difficult-to-solve problems associated with the content of several components in technogenic solutions with similar properties. The aim of the study is to develop an improved technology for extracting metals from metal-containing recycled solutions of metallurgical plants, providing additional production of non-ferrous metals, which contributes to the normalization of the ecological situation in the region. Technogenic formations in the form of metal-containing recyclable solutions of the rare metals production workshop and the vitriol workshop of Almalyk MMC JSC were used as objects of research. The essence of the study is that in the process of ion flotation of technological solutions of copper production of JSC “Almalyk MMC” reagent DEDTK-Na was used, where the maximum extraction of metal ions into the foam product of ion flotation of acidic effluents of the vitriol shop of the copper smelter and washing solutions of sulfur the acid shop of the zinc plant is observed at pH 5. This produces a collective concentrate containing, %: 2.56 Ni; 9.9 Cu; 0.28 Zn; 5.4 Fe. The degree of extraction of metals into the foam product is, %: 98 Ni; 99.7 Cu; 98 Zn; 96 Fe. Research has been carried out to study the duration of flotation with a duration of 4–5 minutes, where the degree of extraction of ions of heavy non-ferrous metals reaches 99%. As a result of the research, a technological and circuit diagram of the apparatus was developed for the processing of utilized metal-containing acid solutions of JSC Almalyk MMC using ion flotation, which makes it possible to ensure the yield of metals up to 99%.

The selective separation of neodymium from aluminum using ion flotation

In this study, fluorine ion was applied as a chelating agent to separate selectively neodymium ion from aluminum ion by ion flotation. The interactions of neodymium and aluminum ions with fluorine ions at different fluorine concentrations and pHs were investigated to determine species ions formed in solution. The results showed that the presence of fluorine ions increased the selective separation of neodymium ion, enhancing the selectivity coefficient during the process. A decrease in the selectivity coefficient was obtained with increasing the concentration of fluorine ion. As the fluorine ion concentration increased from 3.5 to 10 mM, there was an increase in the selectivity coefficient from 2.91 to 30.2 and then decreased using more fluorine. Selective ion flotation results indicated that neodymium ion recovery was higher than that of aluminum ions, indicating the ion recovery order based on the enhancing order of crystal ionic radius. Also, the scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDAX) and Fourier-transform infrared spectroscopy (FTIR) analyses results confirmed higher interaction of fluorine ions with neodymium ions compared to that of the aluminum ions in the solution.

Studies for Ultimate Uranium Separation from Its Low-Content Carbonate Leachate Solutions by Ion Flotation

Studies for Ultimate Uranium Separation from Its Low-Content Carbonate Leachate Solutions by Ion Flotation

Physical-chemical properties of FM-1 reagent as a potential collector for ion flotation of lanthanoids

The physical-chemical properties of the industrial reagent “FM-1” have been investigated. These properties are necessary for evaluating its use as a collector in the processes of concentration of rare earth metal ions by ion flotation. “FM-1”, which is based on sodium salts of aminomethylenephosphonic acids, is used as a flocculant for oil production and purification of process waters from suspended particles and petroleum products. Protolytic equilibriums in aqueous solutions of the reagents were studied. The values of dissociation constants equaling pKa1 = 2.31±0.26 and pKa2 = 8.82±0.34 were determined spectrophotometrically. Surface tension of the reagent solutions at the solution-air interface was studied. The “FM-1” reagent was classified as a strong surface-active substance with the following parameters: Minimal surface tension σmin = 29 mN∙m-1, surface activity G = 0.031 N∙m2∙mol-1, critical concentration of micelle formation 1∙10–3 mol∙L-1. The regularities of the reagent’s interaction with lanthanum (III) ions were studied. A high degree of lanthanum ions’ precipitation (over 99.7 %) was observed over a rather wide interval of pH values (4.00–12.00); at this point, at pH ≥ 7.5, lanthanum hydroxide can co-precipitate. The formation of compounds in a solution with molar ratios [La]:[FM-1] = 1:1 and 1:2 was established by conductometric titration method. The findings of chemical analysis, FTIR spectroscopy and elemental analysis of the isolated precipitates suggested their structural formula. A possibility for the “FM-1” reagent to be used as a collector for the ion flotation of lanthanum (III)ions was shown

Mini review on the synthetic methodology of citric acid functionalized magnetic graphene oxide characterization and its implementation in waste water treatment

Abstract: Water is an essential element for day-to-day activities like agriculture, industry and domestic uses, etc for human beings. Now-a-day, water pollution by heavy metal ion is one of the most crucial environmental issues. Various methods like ion exchange, chemical precipitation, coagulation, flocculation, membrane filtration, adsorption, and flotation have been adopted to get rid of heavy metal ions from the waste water. Among all these methods, the adsorption process has been widely used for the elimination of heavy metals due to its environment friendly, cost-effective nature and easier availability. The commercial adsorbents, bioadsorbents, and nanosorbents possess high removal capacity, thus used for the eradication of heavy metals from waste water. In recent years, nanosorbents are used in environmental remediation as it occupies large surface area and high substance specificity. The present review aims to assemble the role of citric acid functionalized magnetic graphene oxide in waste water treatment. The presence of functional groups like citric acid, Fe2O3 on graphene oxide holds ample of sites which lead increase its surface area and enhance its adsorptivity. The magnetic nature of graphene oxide provides good dispersity in water and makes it easily separable.

Selective recovery of Pb(II) from a waste electrolyte via ion flotation with iminodiacetic acid-functionalized graphene oxide as a nanocollector

In this work, iminodiacetic acid-functionalized graphene oxide (IDA@GO) is prepared and used as a nanocollector for enhancing and selectively recovering Pb(II) from a strongly acidic waste electrolyte via ion flotation. IDA@GO is characterized by Fourier transform infrared spectroscopy, zeta potential measurements and atomic force microscopy. The effects of pH, reaction time, cetyl trimethyl ammonium bromide (CTAB) dosage and aeration rate on the Pb(II) concentration and turbidity of the residual solution are examined systematically. The experimental results show that the adsorption capacity of Pb(II) on IDA@GO can reach 91.21 mg/g at pH 2. After froth flotation, the turbidity of the treated solution decreased to 0.55 NTU under the optimal CTAB dosage and aeration rate. In addition, as compared with GO, the relative selectivity coefficients of IDA@GO are up to 1.304, 1.471, 1.807 and 1.509 for Co(II), Ni(II), Zn(II) and Cd(II), respectively, thereby exhibiting better selectivity performance. Moreover, IDA@GO can be reused as a nanocollector in ion flotation and exhibits ideal regeneration performance. In addition, the recovery mechanism is found to proceed through Pb(II) adsorbing on IDA@GO by electrostatic attraction, ion exchange and surface complexation, with the addition of CTAB improving the hydrophobicity of Pb(II)-loaded IDA@GO flocs, thus achieving the recovery of Pb(II) via froth flotation.

Ion flotation of heavy metal ions by using biodegradable biosurfactant as collector: Application and removal mechanism

• By using the biosurfactant LS, ion flotation can be used to remove heavy metal ions . • The ability of LS to remove heavy metal ions is better than that of SDS . • The high flotation removal performance of LS is due to its structural advantages. • The carboxyl group and amide of LS react with metal ions. • LS reacts with Pb(II) and generates a four-membered ring complex. Ion flotation was used to remove copper(II), lead(II) and chromium(III) from simulated wastewater using a new biodegradable biosurfactants, namely, sodium N-lauroylsarcosinate (LS), and the synthetic surfactant sodium dodecyl sulfate (SDS) as collectors. The use of LS resulted in better removal of metal ions than that achieved with SDS. It was found that the removal efficiency of single metal ions can reach more than 95%. The results showed that the complex formed by surfactant and metal ion was flocculent and loose in structure, which may be the main reason for the slow ion flotation speed. XPS and IR analysis showed that there was a complex reaction between the sulfonic group of SDS and the carboxyl group of LS with metal ions. These findings indicate that the new biosurfactant LS has a better treatment effect on wastewater containing heavy metal ions and compared with industrial surfactants (such as SDS), LS is degradable and environmentally friendly, potentially leading to better industrial application. DFT theory further confirmed the experimental results. The calculated results show that LS has higher complexation ability for Pb(II) than dose SDS. LS reacts with Pb to form a four-membered ring complex containing two O atoms, which has higher stability than the complex containing SDS.