Recovery Of Ilmenite Research Articles

Judicious combinations of gravity, magnetic, electrostatic separators and microwave heat energy on recovery of ilmenite from Humma lean grade beach placer deposit

Microwave heating is an eco-friendly and novel technique for sintering and heating minerals and materials as it has several advantages in terms of phase transformation, energy efficiency, enhancing speed, process simplicity, improved properties. Such heating provides the composite materials to absorb electromagnetic energy volumetrically and transform into heat and produces larger densities as compared to conventional heating. This study focuses on two main objectives: the recovery of ilmenite through a strategic combination of mineral processing equipment, including a spiral concentrator, followed by magnetic and electrostatic separation, and the enhancement of ilmenite concentrate using microwave heat energy on a cleaner magnetic product, followed by electrostatic separation. Continuous magnetic separation results indicate that among the dry high-intensity belt magnetic separator, box mag wet high-intensity magnetic separator and dry rare earth drum magnetic separators, the rare earth magnetic separator yielded the highest quality product. The application of microwave heat energy before the rare earth drum magnetic separator at 1.4 T, followed by high-tension separation, produced the best grade of ilmenite. The magnetic product obtained after microwave treatment contained 98.6% ilmenite, which was further upgraded to a 99.6% ilmenite concentrate through high-tension separation. Therefore, it is recommended that an effective combination of gravity separation, microwave heat energy, rare earth drum dry magnetic separation and high-tension separation be employed to achieve the highest grade of ilmenite concentrate.

Surface modification of ilmenite with sodium persulfate and its effect on flotation performance

Ilmenite is a challenging mineral to float, making the improvement of its floatability a prominent research focus. This study proposes a novel surface modification method using sodium persulfate (Na2S2O8) activation in the sodium oleate system for ilmenite. The activation mechanism was investigated using micro-flotation, zeta potential analysis, adsorption measurement, contact angle measurement, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), flotation kinetics calculation, and thermodynamic analysis. Flotation tests demonstrated a significant increase in ilmenite recovery after Na2S2O8 activation under weakly acidic conditions, particularly at pH 4.0, where recovery increased from 12.41 % to 67.24 %. Zeta potential, contact angle, and adsorption tests revealed that Na2S2O8 activation positively shifted the surface potential of ilmenite, enhancing sodium oleate adsorption and increasing hydrophobicity. FT-IR, XPS, and thermodynamic analyses showed that Na2S2O8 facilitated the conversion of Fe2+ to Fe3+ on the ilmenite surface. Additionally, activation with sodium persulfate increased the Fe3+ content on the surface from 20.13 % to 43.50 %, leading to the formation of a more stable ferric iron oleate. AFM scans confirmed that Na2S2O8 activation significantly increased the area and thickness of sodium oleate adsorbed on the ilmenite surface compared to unactivated ilmenite.

Flotation separation of ilmenite and titanaugite modified by Fe2+-assisted peroxymonosulfate oxidation: Performance and activation mechanism

Efficient separation of ilmenite and titanaugite has always been recognized challenge in modern mineral processing. The use of a heterogeneous Fenton-like oxidation process composed of peroxymonosulfate (PMS) and Fe2+ is promising to address this issue. Flotation findings indicated that effective recovery of ilmenite could be achieved under weak acidic conditions, and a TiO2 recovery of 81.56 % and a grade of 32.16 % concentrate was collected. A series of characterization analyses confirmed that the PMS-Fe2+-mediated Fenton-like reaction in the ilmenite system generated more •OH and SO4•- radicals, which oxidized Fe2+ to Fe3+ on its surface, thus improving the active sites on ilmenite surface. Moreover, PMS-Fe2+ promoted the positive shift of surface charge on ilmenite, facilitating NaOL adsorption and making the surface more hydrophobic. NaOL primarily interacted with Fe active sites on the ilmenite surface and Mg2+ and Ca2+ active sites on the titanaugite surface in the formation as chemisorption. Thus, PMS-Fe2+ activated ilmenite mainly via augmenting the quantity and reactivity of Fe active sites on the surface. In summary, these findings provide the innovative pathways to implement the advanced oxidation processes in mineral flotation.

An innovative process for recovery of ilmenite using mineral phase transformation followed by magnetic separation

Recovery of fine ilmenite is challenging, resulting in significant waste of titanium resources. In this paper, the mineral phase transformation technology was proposed to strengthen the surface magnetism of fine ilmenite. The results demonstrated that in the oxidation stage, the suitable oxidation temperature was 700 °C and the oxidation time was 30 min. In the reduction stage, the ideal reduction temperature was 575 °C, the CO concentration was 20 %, and the reduction time was 3 min. Under the optimized roasting conditions, the roasted sample was separated by staged low-intensity magnetic separation, and titanium concentrate with a TiO2 grade of 46.24 % and recovery of 67.62 % was obtained. The XRD, SEM and VSM analysis implied that the oxidation products of ilmenite were hematite and rutile, where hematite was enriched on the surface of the particles and formed a layer of 2–5 μm. After reduction roasting, the hematite layer was directionally transformed into magnetite, which significantly enhanced the magnetism of the particles and created conditions for the recovery of titanium by low-intensity magnetic separation.

Flotation behavior of ilmenite using 1,10-phenanthroline as novel collector

1,10-phenanthroline (Phen) was introduced as the novel collector for the selective separation of ilmenite from titanaugite. Micro-flotation showed that Phen was a more effective collector for ilmenite flotation from pH 2 to 12 compared with benzohydroxamic acid (BHA), and the maximum increase in ilmenite recovery (~20%) was observed at pH 6. Titanaugite kept at very low level of floatability (recovery < 5%) during micro-flotation test. FTIR and XPS analyses indicated that Phen and BHA adsorbed onto ilmenite surface via chemisorption and the interaction between Phen and ilmenite was intenser than that of BHA. XPS results also showed that Phen reacted with both iron (ferrous and ferric) and titanium on the ilmenite surface. A five membered ring structure appeared to form during the adsorption of Phen onto the ilmenite surface.

The Application of Dextran Sodium Sulfate to the Efficient Separation of Ilmenite and Forsterite, as a Flotation Depressant

A depressant is essential to the effective flotation-based separation of ilmenite and forsterite, based on their comparable physicochemical characteristics. In this work, dextran sodium sulfate (DSS) was initially introduced as a depressant, to aid in the separation of ilmenite and forsterite. Comparing the DSS to conventional natural starch, the results indicate that the forsterite exerts a greater depression over the ilmenite. The difference in recovery of ilmenite and forsterite was 75.44% at 10 mg/L of DSS dosage. The DSS was chemisorbed strongly onto the forsterite surface via Mg active sites, whereas its interaction with the ilmenite surface via physisorption was weak, based on the XPS and molecular-dynamics-simulation analyses. The results of the AFM and QCM-D investigations showed that the DSS adsorption layer on the forsterite surface was larger than those on the ilmenite surface. Consequently, DSS may function as a depressant, to effectively separate forsterite from ilmenite ore.

A novel method for efficient recovery of ilmenite by high gradient magnetic separation coupling with magnetic fluid

Ilmenite is the main raw material for titanium extraction. The vanadium titanium magnetite deposit in Panzhihua has abundant ilmenite resources. A flowsheet combining high gradient magnetic separation (HGMS) and flotation was applied to recover the ilmenite, which had defects of high production cost due to high flotation regent consumption, low ilmenite utilization rate of 20% as ultrafine minerals were directly discharged into tailings, as well as bring a series of environmental problems. In this study, a novel method termed high gradient magnetic separation coupling with magnetic fluid (HGMSCMF) was developed to recovery ilmenite in Panzhihua. Paramagnetic MnCl2 solutions were introduced to eliminate competing capture between ilmenite and titanaugite particles and improve selectivity. Under equivalent TiO2 recovery, TiO2 grade of magnetic products increased significantly with MnCl2 concentration. Pulsating flow could further strengthen the improvement effect of selectivity by magnetic fluids. For the first time, qualified ilmenite concentrate (TiO2 grade > 46%) with TiO2 recovery equal to that in industrial production was obtained only through HGMSCMF (without using flotation) with one roughing and three cleaning processes under the optimal conditions of MnCl2 concentration 40%, applied induction 0.6 T and pulsating frequency 400 r/min. HGMSCMF presents great potential in solving tough problems being faced in processing weakly magnetic minerals. Follow-up studies will focus on recycling and reuse of magnetic fluids for realizing industrial application of HGMSCMF in recovering ilmenite or other refractory weakly magnetic minerals.

Effect of the adding order of sulfuric acid on the flotation behaviors of ilmenite and titanaugite and its functional mechanism

The influence of changing the adding order of sulfuric acid (H2SO4) and sodium oleate (NaOL) collector on the flotation of ilmenite and titanaugite was investigated through a series of experiments. Flotation experiments showed that adding NaOL preferentially could improve the ilmenite recovery and reduce the titanaugite recovery, decreasing the H2SO4 dosage in half. Microflotation and ICP analyses indicated that the total ions in pulp caused by the dissolution of H2SO4 prevented the adsorption of NaOL on ilmenite surfaces, but had little effect on titanaugite. However, when adding NaOL firstly, the pre-adsorption of NaOL on ilmenite surfaces weakened the dissolution of H2SO4, while the weak pre-adsorption of NaOL on titanaugite surfaces was destroyed by the dissolution of H2SO4. Thus, altering the adding order of H2SO4 and NaOL could reinforce the adsorption difference of NaOL on ilmenite and titanaugite surfaces, which was evidenced by the contact angle, zeta potential, and AFM analyses.

Induced roll magnetic separator applied for high grade ilmenite separation from mining tailing

This article aimed to separate ilmenite (FeTiO3) mineral from tin tailing applying a single splitter IRMS (Induced Roll Magnetic Separator). Ilmenite mineral is the substantial main source for TiO2. This work used air table middling for feeding. The mineral components of middling feeding from air table using grain counting analysis were found as follows: cassiterite (48.61%), ilmenite (21.36%), monazite (18.56%), pyrite (4.60%), zircon (5.85%), quartz (0.71%), anatase (0.27%), and tourmaline (0.02%), It was found that electrical current and opening of single splitter affected the degree of separation addressing to ilmenite recovery and ilmenite grade. The finding showed that current of 15 Ampere and single splitter with opening 4.25 cm yielded ilmenite recovery more than 74%. The high grade ilmenite (90.46 %) and recovery of 29.38% was obtained using 5 Ampere with single splitter opening of 1.0 cm. Up to date, the study on ilmenite separation from tailing only focused on the effect of current, however, the effect of single splitter magnetic separator to enhance ilmenite recovery from other paramagnetic minerals such as monazite, siderite, xenotime and tourmaline has not yet been reported.

Experimental investigation of an optimised tribocharger design for space resource utilisation

Triboelectric charging and free-fall separation are attractive technologies for lunar mineral beneficiation. Here, an optimised tribocharger design was built and evaluated under terrestrial conditions. The charging behaviour of pure silica and ilmenite were tested using the optimised design, as were mixtures of silica and ilmenite, and samples of lunar regolith simulant JSC-1. Pure silica and ilmenite acquired negative and positive charge, respectively, through contact with the tribocharger. The tribocharger affected significantly the movement of the pure minerals in the electrostatic field. Results from the binary mixtures indicate that ilmenite recovery is independent of initial ilmenite concentration, and can be predicted from the mass distribution of pure ilmenite samples. For JSC-1, the tribocharger was found to increase the density of the material in certain collectors, indicating an upgrading of denser constituents. The optimised tribocharger design has a significant effect on the charging and separation performance.

Improvement of ilmenite flotation via the benzohydroxamic acid synergistic mechanical activation

In this paper, the effect of the benzohydroxamic acid (BHA) synergistic mechanical activation on ilmenite flotation was systematically investigated. Flotation results revealed that the flotation recovery of ilmenite significantly increased with the addition of BHA before grinding as compared to the conventional process flow. Similar trend was observed in the flotation test of artificial mixed mineral. The addition of BHA to the mill has little effect on the size distribution of ilmenite, but it can increase the content of crystal surface (104) with the lowest surface energy of ilmenite. The results of Fourier-transform infrared spectroscopy (FT-IR) analysis showed that the addition of BHA before grinding resulted in improving the intensity and kinds of characteristic absorption peaks of BHA on the ilmenite surface. The addition of BHA to the mill effectively facilitated the interaction between ilmenite and BHA. Besides, the result of flotation kinetics demonstrated that the flotation kinetics of ilmenite could be well evaluated with the first-order kinetic model. And the flotation kinetic constant was improved by adding BHA before grinding, which was conducive and beneficial for enhancing the ilmenite flotation.

Activation of ilmenite flotation by sodium chlorite in the sodium oleate system

Development of environmentally friendly, energy-efficient, methods to improve flotation recovery of ilmenite is significant. Herein, a new method of ilmenite surface modification was developed based on sodium chlorite activation using sodium oleate as a collector. The mechanism of sodium chlorite activation was investigated via microflotation, zeta potential, Fourier transform infrared (FT-IR), contact angle, X-ray photo-electron spectroscopy (XPS), and atomic force microscopy (AFM) analyses. Flotation tests showed that the recovery of ilmenite after sodium chlorite activation was substantially increased in the sodium oleate system, with the highest recovery of 83.18 % at pH 8. Under the simultaneous influence of sodium chlorite and sodium oleate, the zeta potential of ilmenite tended to be more negative than that of sodium oleate-treated ilmenite, and the adsorption of sodium oleate on the surface was increased. FT-IR and XPS results showed that sodium chlorite induced a chemical reaction on the surface of ilmenite, converting more Fe2+ to Fe3+ and strengthening the adsorption of sodium oleate. Both contact angle and AFM results confirmed that the activation of ilmenite by sodium chlorite significantly increased the number of active sites on the surface. Compared to the ilmenite without activation, the hydrophobic layer was thicker, thereby improving the floatability.

α-Amino Phosphonic Acid as the Oxidized Ore Collector: Flexible Intra-Molecular Proton Transfer Providing an Improved Flotation Efficiency

The efficient separation of ilmenite is a difficult problem in minerals flotation. For this issue, α-aminooctyl phosphinic acid (APA) was developed as a selective collector to separate ilmenite. The flotation test result showed that APA was more efficient for improving ilmenite recovery compared with octylphosphonic acid (OPA). Adsorption, ZETA and FTIR measurements proved that the chemical interaction between collector APA and the surface of ilmenite was stronger than OPA, while the result is completely opposite in the case of titanaugite. Moreover, XPS test and DFT calculations indicated that the collector APA was coordinated with the surface of ilmenite through P-O-Fe and P-O-Ti bonding. The amine group in the α-site of the phosphonyl group facilitated APA to be a stable zwitterion in the solution, which greatly enhanced the nucleophilicity of the phosphonic acid group. On the other hand, more appropriate coordination energy was another reason for the superior collecting selectivity of APA than OPA.

Flotation behavior and mechanism of ilmenite using ferrate as activator

• A novel activation reagent for ilmenite flotation was proposed. • Na 2 FeO 4 was used as a surfactant to change the valence state of Fe on the ilmenite surface. • Na 2 FeO 4 increased the active sites on the surface for collector interaction/adsoption. • Fe 3+ content significantly increased, and sodium oleate readily interacted with Fe 3+ . The activation property of ferrate on the flotation of ilmenite using sodium oleate as collector was studied in this work. Flotation tests reveal that the sodium ferrate strongly activated ilmenite at a pH range from 5 to 10. The addition of sodium ferrate increases ilmenite's surface active sites and enhances the interaction with sodium oleate. The recovery of ilmenite can be increased from 62% to more than 90% at pH 6. After ferrate treatment, the surface Zeta potential of ilmenite becomes more positive, and the isoelectric point (IEP) increases from pH 5.5 to pH 7.2. In the sodium oleate system, the Zeta potential becomes more negative after sodium ferrate treatment from pH 5 to 9. Reaction thermodynamic analysis shows that oleate ion is easier to adsorb with Fe(III) species on the surface of ilmenite at pH 6. The results of Fourier-transform infrared spectroscopy (FT-IR) analysis show that more active sites of metal ions are formed on the surface of ilmenite after sodium ferrate treatment. X-ray photoelectron spectroscopy (XPS) test shows that after ferrate treatment in the collector system, the Fe2p3 content on the surface of ilmenite increases from 2.15% to 3.37%, and the Fe(III) content increases from 19.81% to 33.34%, which makes it easier for sodium oleate to adsorb with ilmenite chemically. The addition of sodium ferrate makes ilmenite's surface have more Fe(III) active sites, which helps improve the flotation recovery of ilmenite.

New insight into adsorption of novel ternary mixed collector in ilmenite–titanaugite flotation system

In this study, a self-assembled ternary mixed collector, Pb–BHA–NaOL (PBN), was used for the flotation of ilmenite from titanaugite. The internal assembly mechanism and interfacial adsorption behavior of the collector were comprehensively explored. The highest flotation separation performance (ilmenite recovery, 95.2% vs. titanaugite recovery, 12.6%) in the system was achieved at pH6. New evidence for various assembly behaviors in the collectors, including electrostatic attraction, chemical bonding, and hydrogen bonding, were found using zeta potential and in situ attenuated total reflectance Fourier transform infrared spectroscopy (in situ FTIR) combined with 2D correlation spectroscopic analysis. The difference between the adsorption configurations of PBN on the surfaces of the two minerals were visualized by time-of-flight secondary ion-mass spectrometry. X-ray photoelectron spectroscopy analyses confirmed that the high amount of Ca and Mg ions on the surface of titanaugite did not permit the collector species to form a strong bond with it, which was the main reason for the inadequate floatability of the mineral. Based on this analysis and discussion, different adsorption processes of Pb–BHA–NaOL on the surfaces of ilmenite and titanaugite are described in detail.

Application of Waste Engine Oil for Improving Ilmenite Flotation Combined with Sodium Oleate Collector

Collectors commonly have synergetic effects in ores flotation. In this work, a waste engine oil (WEO) was introduced as a collector to an ilmenite flotation system with sodium oleate (NaOL). The results show that the floatability of ilmenite was significantly improved by using WEO and NaOL as a combined collector. The recovery of ilmenite was enhanced from 71.26% (only NaOL) to 93.89% (WEO/NaOL combined collector) at the pH of 6.72. The optimum molar ratio of NaOL to WEO was about 2.08 to 1. The WEO and NaOL also have synergetic effects for the collection of ilmenite, because to obtain the ilmenite recovery of 53.96%, the dosage of 45 mg/L NaOL is equal to 38.56 mg/L WEO/NaOL combined collector (30 mg/L NaOL + 8.56 mg/L WEO). In other words, 15 mg/L of NaOL can be replaced by 8.56 mg/L of WEO. It is an effective way to reduce the dosage of the collector and reuse WEO. Therefore, it is a highly valuable and environmentally friendly approach for WEO reuse. WEO mainly consists of oxygen functional groups, aromatics, and long-chain hydrocarbons, especially for the RCONH2 and RCOOH, thereby forming a strong interaction on the ilmenite surface. The adsorption mechanism of waste engine oil and sodium oleate on the ilmenite surface is mainly contributed by chemical adsorption. Therefore, WEO exhibits superior synergistic power with NaOL as a combined collector. Herein, this work provided an effective collector for ilmenite flotation and a feasible approach for reducing NaOL dosage and recycling WEO.

Enhanced adsorption of salicylhydroxamic acid on ilmenite surfaces modified by Fenton and its effect on floatability

This work reports a new method of using Fenton to oxidize and modify the ilmenite surface using salicylhydroxamic acid (SHA) as the collector. The activation mechanism of this process was studied by analyzing changes that occurred on the ilmenite surface. Micro-flotation showed that the maximum recovery of ilmenite after treatment with Fenton increased by 37% and attributed to the increase in the adsorbed SHA amount on the ilmenite surface. Zeta potential and XPS measurement data showed that Fenton promoted the conversion of Fe2+→Fe3+ on the ilmenite surface that enhanced SHA adsorption. After adding Fenton, the Fe-SHA complex (formed in the pulp) interacted with the O sites of ilmenite surfaces, and improved the ilmenite floatability. The infrared spectra of the ilmenite+Fenton+SHA system showed several intense bands that indicated enhanced SHA chemisorption on the ilmenite surface. Thus, ilmenite treatment with the Fenton promoted its surface reactivity caused SHA to bind with the ilmenite surface and enhanced the ilmenite floatability.

Study on the flotation behavior and interaction mechanism of ilmenite with mixed BHA/NaOL collector

The mixed BHA/NaOL collector was studied to improve the floatability of ilmenite in the presence of lead ions. The mechanism was discussed through surface tension measurements, zeta potential measurements, adsorption amount measurements, and XPS analysis. Microflotation results show that the mixed BHA/NaOL collector exhibited a better performance on the floatability of ilmenite than single BHA and NaOL collector. The recovery of ilmenite was 92.9% when the molar ratio of BHA/NaOL was set to 7:3. The adsorption amount of mixed collectors on the ilmenite surface was greater than that of equivalent single BHA and NaOL. The results of surface tension suggest that there was synergism between BHA and NaOL in aqueous solution. Zeta potential results indicate that mixed BHA/NaOL adsorbed onto ilmenite surface and had a more negative shift than single BHA. XPS results further confirm that BHA and NaOL adsorbed onto the ilmenite surface through chemisorption and hydrogen bonds.

Optimized magnetic separation for efficient recovery of V and Ti enriched concentrates from vanadium-titanium magnetite ore: Effect of grinding and magnetic intensity

We present an optimized magnetic separation process to improve the recovery of high-content vanadium and titanium concentrates from vanadium‑titanium magnetite (VTM) ore. The ore chunks were crushed using jaw crushers and then grinded in a laboratory rod mill for different grinding times and studied. Vanadium recovery was dependent on maximizing magnetite and ilmenite recovery. Ilmenite, which is the main source for titanium, existed in the stripes within magnetite; it got pulverized first during milling and remained as relatively coarse particles of magnetite. A grinding time of 15 min was determined as optimum for the grinding conditions of this study, based on the degree of liberation, the grade, and recovery of vanadium. The effect of varying magnetic intensities on the separation behavior of the pre-concentrates was analyzed through magnetic separation of the ground VTM samples. The grade and recovery attained for the vanadium concentrates were 1.12% and 63%, respectively. In addition to vanadium, titanium concentrates were also obtained by medium-intensity magnetic separation and the grade and recovery were 38% and 75%, respectively.

Surface modification of ilmenite and flotation improvement using Fenton as an oxidant

In this work, we propose a new method to activate ilmenite using Fenton as an oxidant and a surface modifier. The activation mechanism of Fenton on ilmenite was investigated through micro-flotation experiments, zeta-potential measurement, adsorption tests, Fourier transform infrared (FT-IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Both the micro-flotation and adsorption experiments showed that flotation recovery of ilmenite was significantly improved after activation by Fenton. Compared with ilmenite without Fenton activation, zeta-potential measurement and XPS analysis demonstrated that the number of active sites on the surface of ilmenite increased. A new characteristic adsorption peak appeared in the FT-IR spectrum, and chemical adsorption of oleic ions on the surface of ilmenite was improved after treatment with Fenton. Therefore, Fenton activation promotes the conversion of Fe2+ to Fe3+ on the mineral surface and enhances adsorption of the collector to ilmenite, thereby increasing ilmenite recovery.