Ore Flotation Research Articles

Improved visible-light-driven activity of micro graphite/BiOI nanocomposite for effective removal of xanthate from wastewater

The visible light responsive micro-powder graphite (Mic-g)/BiOI nanocomposite was prepared by hydrothermal method to effectively remove the xanthate residue in sulfide ore flotation wastewater. The effects of different weight ratios of graphite in composites on photocatalytic activity were investigated. Under visible light, the 5wt% Mic-g/BiOI composite exhibited the highest degradation efficiency (94.36%) and the largest rate constant (0.02273 min−1) which was about 4.3 times higher than that of pure BiOI. The enhanced photocatalytic activity was mainly due to the synergy of a good contact interface between BiOI and graphite with good conduction resulting in the carriers’ rapid transfer. In addition, the mechanism of enhanced photocatalytic activity during the reaction was also investigated. The free radical trapping experiment demonstrated that the main active species in the photocatalytic process are •OH. This work provides a simple and effective approach to synthesizing the visible-light-driven photocatalyst with high efficiency for xanthate wastewater treatment.

Study on inhibition effect and mechanism of sodium humate in hematite reverse flotation

The inhibitor can improve the hydrophilicity of minerals and prevent minerals from interacting with collectors. It plays an important role in the reverse cation flotation of iron ore, and it has become the focus of current research to find efficient, environmental friendly and cheap inhibitors. Sodium humate (NaHA) is a product extracted from weathered Lignite by means of biodegradation and organic decomposition. In this study, this new inhibitor NaHA was used to separate hematite and quartz. The results of micro-flotation showed that an appropriate concentration of NaHA could selectively inhibit hematite and realize the effective separation of quartz and hematite. Zeta potential and adsorption measurement results showed that after treatment by NaHA, the negative shift of zeta potential of hematite was more obvious, and could prevent the further adsorption of dodecylamine (DDA). The adsorption capacity of NaHA on hematite surface was much greater than that on quartz surface. FTIR results showed that there was chemisorption of NaHA on the surface of hematite but no on the quartz. XPS analysis again confirmed that NaHA may adsorb on the surface of hematite through coordination with surface iron.

Rationale for efficiency of flotation in the conditions of wetting film heating

When studying the aggregative stability of dispersed systems by sediment volumetry, nanobubbles are formed due to water structure imperfections in the contact area, and the coalescence of nanobubbles results in a hydrophobic attraction force. Changes in the aggregative stability of aqueous dispersions of particles can be explained as follows: water molecules with a high potential of interaction with medium molecules are difficult to flow into the interfacial gap between particle surfaces, and the outflow of water molecules with a high intensity of interaction with a solid surface is impaired. Excessive osmotic pressure between hydrophilic surfaces causes their hydrophilic repulsion, and excessive osmotic pressure of the surrounding water (reduced osmotic pressure between surfaces) causes hydrophobic attraction of the surfaces. To change the result of flotation, it is sufficient to bring the heat flow to a thin liquid layer of nanoscale thickness with the action of forces of structural origin localized inside, which determine the stability of wetting films. To increase the temperature in the interfacial gap between theparticle and the bubble due to the heat of water vapor condensation, it is proposed to use a mixture of air with hot water vapor as a gas during flotation. The developed flotation method was tested in the flotation of gold-bearing ores. The rational vapor consumption determined based on the factorial experiment results is 10.7·10–3kg/(s·m2) at a xanthate consumption of 1.74 g/t. The rougher flotation operation used a jet method of flotation circuit design, which provides for the combination of the initial feed and the rough concentrate. In comparison with ore flotation according to the factory scheme, the yield of concentrate sent for hydrometallurgical processing is 23.4 rel.% less while maintaining the gold recovery level achieved.

Effect and mechanism of the xanthate/H2O2 addition order on flotation separation of chalcopyrite and sphalerite

Oxidation will affect the flotation of sulfide ore, but both sulfide ore and xanthate are easily oxidized, the role of oxidation in the flotation separation of sulfide ore is still unclear. In this study, different single mineral flotation tests were designed to explore the role of hydrogen peroxide (H2O2) in the flotation separation of chalcopyrite and sphalerite, and artificial mixed minerals tests was conducted to verify the selective depression effect of H2O2. Ultraviolet–visible (UV–vis) spectrometer, inductively coupled plasma-mass spectrometry (ICP-MS) measurement, microcalorimetry measurement, contact angle measurement, and Fourier transform infrared (FTIR) spectrometer were used to discuss the depressive mechanism of H2O2 on sphalerite. Flotation tests with different dosing methods show that mineral self-oxidation is the main reason for its depression. Both the chalcopyrite and sphalerite can be oxidized by H2O2, and the PBX adsorbed on its surfaces can also be desorbed by H2O2. However, sphalerite is easier to oxidize than chalcopyrite, and the PBX adsorbed on the surface of sphalerite is also easier to be desorbed. Therefore, sphalerite is selectively depressed by H2O2 in the flotation of chalcopyrite in the order of “mineral + PBX + H2O2″.

Effect of the foaming performance of ammonium dibutyl dithiophosphate on the flotation of slime-containing copper sulfide ore

Effect of the foaming performance of ammonium dibutyl dithiophosphate on the flotation of slime-containing copper sulfide ore

The effects of ultrasonic wave on heterogeneous coagulation and flotation separation of pentlandite-serpentine

It is well known that in the flotation of copper-nickel sulfide ore, pentlandite and serpentine are easy to form hetero-aggregation, which makes it difficult to separate them. Therefore, dispersion operation is indispensable, including chemical and physical dispersion. Chemical dispersion is usually achieved by adding dispersing reagents, which is widely used in mineral flotation, while the study of ultrasonic dispersion in copper-nickel sulfide ores in physical dispersion is less reported. Thus ultrasonic dispersion technology was introduced to weaken the hetero-aggregation and to improve the floatability of pentlandite. Through the implementation of a series of conditional tests of influence factors including ultrasonic site, ultrasonic probe type, ultrasonic time, and ultrasonic power, the optimum ultrasonic dispersion system was demined, and the results showed that the ultrasonic power was the key factor affecting the dispersion of pentlandite-serpentine. Then the dispersion mechanism of ultrasonic was revealed by means of supernatant turbidity measurements, particle-size distribution (PSD) analyses, scanning electron microscopy (SEM), and atomic force microscope (AFM) in succession. Coupled with supernatant turbidity measurements, PSD analyses and SEM images of flotation concentrates all confirmed that the ultra-fine serpentine particles coating on the coarse pentlandite particles were effectively dispersed. AFM analyses depicted the morphological changes of surface roughness treated by different ultrasonic power, and confirmed that the ultrasonic power of 200 W could increase the surface roughness and floatability of pentlandite but decrease that of serpentine. Thus, the difference in floatability between the two minerals were enlarged so as to achieve efficient separation of the two minerals. The results of this research are helpful to understand clearly the mechanism of ultrasonic dispersion of pentlandite-serpentine, which provides an alternative dispersion technology and exhibits great potential for further study and application.

Effect of Ca2+ dissolution and migration transformation from phosphorite on the surface properties of dolomite

The phosphate ore flotation slurry process requires the addition of H2SO4 as a pH adjuster; this can cause the Ca2+ on the mineral surface to dissolve and combine with SO42− to form CaSO4, thereby changing the surface properties of dolomite. In this study, the effects of Ca2+ dissolution and CaSO4 upon the surface properties of dolomite in a phosphate ore flotation slurry system were investigated. The results show that under the same conditions and different pH adjusters, the dissolution of Ca2+ in the phosphate ore slurry varies in the order H2SO4 > HNO3 > HCl, increasing and then decreasing with increasing slurry preparation time. Under the same conditions, the maximum Ca2+ concentrations in fluorapatite, dolomite, and calcite slurry were 0.036, 0.020, and 0.037 mol/L, respectively. Surface tension and contact angle experiments showed that Ca2+ increases the surface tension of the sodium oleate (C18H33NaO2) solution, which hinders foaming. CaSO4 decreases the contact angle of the dolomite surface. Solution chemistry calculations, zeta potential measurements, and X-ray photoelectron spectroscopy (XPS) analysis show that the dissolved Ca2+ partly produces adsorbed CaSO4 on the dolomite surface, and the Ca2+ reacts with oleate to form calcium oleate; both methods together inhibit the hydrophobicity of the dolomite surface.

Effect of n-octanol on impurity removal by reverse flotation of magnesite ore

Dodecylamine is one of the most commonly used amine collectors for the reverse flotation of magnesite ore. Through a combination of experimental research and computational simulation, the effect of n-octanol on the removal of impurities by the reverse flotation of magnesite ore was studied. The test results show that when the dosage of dodecylamine was 60 mg/L, the flotation rates of magnesite and dolomite were 59.53% and 58.02%, respectively, and the flotation rate of quartz was 97.60%. In the presence of n-octanol, the flotation rate of magnesite decreased to 56.41%, and the flotation rates of dolomite and quartz increased to 61.30% and 99.59%, respectively. The test results show that the addition of n-octanol can improve the selectivity of minerals under the same amount of collector. The adsorption of dodecylamine (dodecylamine and n-octanol) on the surface of magnesite, dolomite and quartz was simulated using quantum chemical calculations based on density functional theory (DFT) and implemented in the CASTEP module of Materials Studio. The results show that dodecylamine can adsorb to magnesite, dolomite and quartz, and the adsorption effect was strongest on quartz. After adding n-octanol, the population value of the bond between the agent and magnesite decreased from 0.19 to 0.17, indicating that the adsorption effect of the agent on magnesite was weakened. The population value of the bond between the drug and dolomite increased from 0.19 to 0.23, indicating that the adsorption effect of the drug on dolomite was enhanced. H28, H29, and H2 in the drug form bonds with O12, O20, and O20 on the surface of quartz (101), respectively, and the population values were 0.43, 0.25, and 0.09, respectively. The adsorption sites of the drug and the quartz were increased, and the adsorption effect of the quartz was markedly improved. The test and simulation results show that the dosage of the agent can be reduced in the presence of n-octanol. N-octanol is not only beneficial to the removal of silicon by amine reverse flotation but also has a certain beneficial effect on the removal of calcium by reverse flotation.

Bulk flotation followed by selective leaching with biogenic ferric iron is a promising solution for eco-friendly processing of complex sulfidic ores.

The development of cost-effective environmentally friendly technologies is of current importance for the intensification of metal recovery. Here, we propose a new direction in the use of a two-step process for the treatment of complex sulfidic ores. In the first step, ore flotation allows the obtainment of a bulk copper-zinc concentrate and low-toxicity waste. In the second step, zinc is selectively extracted by chemical leaching with a biogenic ferric iron solution, while copper is accumulated in the leach residue. Importantly, the efficiency of this step depends on the chemical and mineralogical composition of polymetallic concentrates. Four samples of the copper-zinc sulfide concentrate with various contents of copper and zinc have been leached in multiple cycles at 80°C, 10% of pulp density, and pH 1.3-1.5. The leaching of the concentrate that contained 14.7% of copper and 5.0% of zinc for three leaching cycles (total duration, 5.75h) allowed the obtainment of a leach residue containing 15.3 and 0.14% of copper and zinc, respectively. At the same time, the leaching of another concentrate that contained 19.2% of copper and 2.64% of zinc after one leaching cycle (total duration, 0.67h) led to copper and zinc contents of 19.1 and 0.72%, respectively, in the leach residue. Therefore, the treatment of only two concentrates allowed the obtainment of high-grade copper concentrates containing low amounts of zinc. Ferric iron, the oxidant of sulfide minerals, was fully regenerated in leachate within 30-35h at 40°C using an acidophilic microbial community dominated by Leptospirillum ferriphilum, Sulfobacillus spp., and Ferroplasma acidiphilum. The loss of copper and zinc in solid waste of the bioregeneration did not exceed 1.0% and 1.8%, respectively. The proposed flowsheet of bulk concentrate processing has several important advantages over conventional technologies, including short duration of leaching, formation of low-toxicity solid waste, and pyrometallurgical processing of only high-grade copper concentrates. This approach can be a promising solution for the efficient processing of polymetallic bulk concentrates.

Scientific heritage of professor G. V. Illyuvieva

Our mining industry has been built by women as well as men. A mining processing engineer, a graduate of the Leningrad Mining Institute, a specialist in the field of ore flotation, sorption, and extraction, head of the Department of General and Physical Chemistry of the Mining Institute for 16 years (1966–1981), and a participant in the Great Patriotic War, Galina Viktorinovna Illuvieva will be remembered by generations to come as an outstanding researcher, a talented leader, and a mentor. The article systematizes documentary material on the life of Galina Illuvieva and analyzes her contribution in the scientific and pedagogical fields. Her research resulted in improved technology for the complex processing of ores at a number of deposits of ferrous, non-ferrous, and rare metals, and coal. Under the leadership of Galina Illuvieva, the Department of General and Physical Chemistry reached a new milestone in significantly increasing its material and technical resources and the amount of work commissioned by the industry and ensuring the successful defense of candidate dissertations on urgent scientific and technical topics. As a teacher, Galina Illuvieva enjoyed high prestige and respect among students. During the war, she worked selflessly as a scrub nurse in the besieged Leningrad at the Military Medical Academy and at the evacuation hospital. Galina Illuvieva was awarded two medals for her courage during the Great Patriotic War and held the Order of Lenin and multiple medals for outstanding scientific, pedagogical, and social work.

Flotation of Copper Ores with High Cu/Zn Ratio: Effects of Pyrite on Cu/Zn Separation and an Efficient Method to Enhance Sphalerite Depression

Porphyry copper deposits are important sources of copper and typically processed by flotation to produce copper concentrates. As mining areas become deeper, the amounts of impurities, such as sphalerite, can be increased in copper ores, so the appropriate depression of sphalerite floatability should be achieved to obtain saleable copper concentrates. In this study, the flotation behaviors of chalcopyrite and sphalerite in model samples mimicking copper ores with high Cu/Zn ratios (i.e., the ratio of chalcopyrite/sphalerite = 13:1) were investigated with zinc sulfate as a depressant for sphalerite. In addition, the effect of pyrite—a major gangue mineral in copper ores—on the depression of sphalerite floatability with zinc sulfate was examined. When sphalerite and chalcopyrite coexisted, the floatability of the former was effectively depressed by zinc sulfate (Zn recovery: <12%), whereas the presence of pyrite promoted the release of Cu2+ due to the galvanic interaction with chalcopyrite, which resulted in the elimination of the effectiveness of zinc sulfate in depressing sphalerite floatability (Zn recovery: >90%). Despite the presence of much higher amounts of chalcopyrite and pyrite than sphalerite, the application of nitrogen (N2) gas limiting the galvanic interaction between pyrite and chalcopyrite by reducing the dissolved oxygen (DO) concentration in the system effectively depressed the floatability of sphalerite (Zn recovery: <30%).

New insights on depressive mechanism of citric acid in the selective flotation of dolomite from apatite

The effective separation of apatite and dolomite is always the focus of phosphate ore flotation research. The effect of citric acid (CA) on the flotation reaction of apatite and dolomite was studied. The flotation behavior of these two minerals was evaluated through micro-flotation experiment. The results of micro-flotation experiment indicate that CA has selective depression for apatite, but has no obvious depression for dolomite The depression mechanism of CA on apatite and dolomite was analyzed by infrared spectroscopy (FTIR), Zeta potential measurement and XPS analysis. CA adsorbed on apatite and dolomite to varying degrees via FTIR test and Zeta potential measurement. The results from XPS test showed that CA formed chemisorption on apatite surface to form organic complex, but not on dolomite surface. In addition, the results of adsorption amounts and mineral dissolution experiments further support the selective depression mechanism of apatite. Through adsorption amounts test and surface dissolution test, it is found that the surface of dolomite dissolves strongly, and a large amount of calcium ions are generated in the solution. Calcium ions can chelate with citric acid and consume citric acid. At the same time, the calcium density on the surface of dolomite is higher than that of apatite, and a large amount of dissolution occurs on the surface of dolomite. However, the density of remaining active sites on the surface of dolomite is still high, and sodium oleate can still be adsorbed on the surface of dolomite. The degree of surface dissolution of apatite is less. CA occupies the active sites on the surface of apatite, making it difficult for sodium oleate to adsorb on the surface of apatite, resulting in poor apatite floatability.

Using reagents in the form of inverse microemulsion for lead and zinc sulfide flotation

The paper presents the results of studies on the use of collecting agents in the form of an inverse microemulsion (IМE) of the «water in oil» type (i.e. suspended water droplets are in the oil phase) for the flotation extraction of lead and zinc minerals. Lead and zinc concentrates, lead-zinc ore were used as initial samples for flotation. The content of galena in the lead concentrate was 74.7 %, and the content of sphalerite in zinc was 78.7 %. Basic collecting agents in the IМE composition were potassium butyl xanthate (PBX) and kerosene. A nonionic surfactant (NSA) was used for IМE stabilization. Casein was used as additives to main reagents to remove the negative effect of osmotic pressure during the IМE preparation. Casein was transformed into the active soluble form using sodium sulfide. The particle size in the inverse microemulsion was 12.38 nm. In flotation tests, the following options for feeding reagents to the flotation pulp were studied: IМE, IМE + frother, potassium butyl xanthate + frother. The T-92 reagent was used as a frother. PBX consumption as part of IME and in the traditional feeding was 26 g/ton. The results of laboratory tests showed that the method of feeding flotation reagents in the form of IМE leads to both an increase in the flotation rate of lead and zinc sulfides and an increase in their recovery into a foam product. In addition to the increased flotation speed, tests with the use of IМE in the bulk lead-zinc ore flotation cycle showed an increase in extraction into the ultimate concentrate by 10.8 % for lead, by 38.5 % for zinc, in comparison with the traditional feeding of reagents (collector + frother). An increased selectivity of the IМE effect in relation to zinc sulfides, in comparison with lead sulfides, was noted. The flotation rate coefficient of sphalerite is 7.8 times greater than that of galena. An increase in extraction into the ultimate zinc concentrate is also higher and amounted to 16.78 %, while for the lead concentrate it is 1.9 % under the same conditions.

Effects of dissolved fluoride in phosphate ore flotation systems on the surfaces properties of dolomite

Fluoride is an important component phosphate ore, and the leaching and migration behavior of fluoride during the phosphate ore flotation and slurry transfer processes affects the surface properties of its vein minerals in phosphate ore. This study investigates the effects of this behavior on the surface properties of dolomite. The results showed that the fluoride concentration in the slurry gradually decreased with increases in the slurry-making time and temperature. Adsorption experiments and contact angle tests showed that F- could adsorb on the dolomite surface, which reduced the hydrophobicity of this surface when sodium oleate (NaOL) was the collector. Zeta potential tests, solution chemistry calculations and X-ray photoelectron spectrometry (XPS) analysis showed that F- reacted with Ca2+ and Mg2+ on the dolomite surface to form CaF2 and MgF2, both of which inhibited NaOL from interacting with dolomite, thus decreasing the hydrophobicity of the dolomite surface.

Froth stabilities and iron ore flotation of collectors 3-dodecyloxypropanamine and 3-tetradecyloxypropylamine: An experimental and molecular dynamics study

In the mineral processing industry, froth properties are essential. To separate iron minerals and gangue minerals in a flotation mill, froths that are both too stable and fragile are useless for obtaining qualified concentrate in the mining industry. We tried to develop two collectors to adjust the froth stability during flotation. In this study, we first researched the froth stabilities of collectors 3-dodecyloxypropanamine (DOPA) and 3-tetradecyloxypropylamine (TOPA). Contact angle measurements and surface tension measurements were used to research the hydrophobicity of DOPA and TOPA and to predict its flotation performance. Froth stability measurements and molecular dynamics (MD) were conducted to investigate the froth properties of DOPA, TOPA, and dodecyl amine (DDA), and to reveal the froth mechanism of flotation. The film interface models were built using software Materials Studio 2017 software, and MD was used to simulate the flotation system. The interaction formation energy (IFE) was calculated to compare the froth film strength of the three collectors. Surface tension measurements indicated that DOPA and TOPA were more robust collectors in decreasing water surface tension than DDA. The froth stability measurements showed that the DDA froth was the most stable of the froths with the three collectors, consistent with the MD simulations of the foam models. Furthermore, the adsorption configuration of the interface of DOPA or TOPA and solution was drawn, and the numbers and the average length of different kinds of hydrogen bonds of the three configurations were counted and calculated. We can infer that the hydrogen bonds between the O atom of water and the —NH2 of DOPA or TOPA are not the main force of their IFE, and the main force is van der Waals force. Finally, the micro-flotation of the artificial mixed mineral was conducted to verify the previous prediction of DOPA and TOPA. This paper provided a new case to adjust the flotation performance by developing a collector and predicting its froth stability.

Selective flotation of chalcopyrite from galena using a novel collector benzoic diethylcarbamothioic thioanhydride: An experimental and theoretical investigation

The flotation separation of chalcopyrite and galena has always been the focus of production. Benzoic diethylcarbamothioic thioanhydride (BDT) is a novel chelating collector that has shown a certain application strength in the field of sulfide ore flotation. In this research, micro-flotation tests, zeta potential tests, Fourier transform infrared spectroscopy measurements, X-ray photoelectron spectroscopy measurements, and density functional theory (DFT) calculations were used to investigate the selective recovery and selective adsorption of BDT on chalcopyrite and galena. The flotation results showed that BDT had good flotation selectivity for chalcopyrite and galena, which achieved up to 96.67 % and 50.26 %, respectively, at pH 6 using a collector dosage of 100 g/t. The analysis of the adsorption mechanism showed that CS and CO in BDT are mainly involved in the adsorption process. On the surface of chalcopyrite, CS and CO can form a six-membered chelating ring with Fe or Cu sites. BDT can also be adsorbed on the surface of galena in the same way, but the adsorption strength is weaker than that on the surface of chalcopyrite.

Effect of sodium metabisulfite and slaked lime on the floatability and surface properties of chalcopyrite

In the flotation of complex copper ores containing chalcopyrite in seawater, sodium metabisulfite (SMBS) has been widely used as a pyrite depressant. Here, calcium ions in seawater or in process water because of pH control using lime (CaO) or slaked lime (Ca(OH) 2 ) can affect the floatability of chalcopyrite. However, the effect of SMBS on the floatability of chalcopyrite in the presence of calcium ions is unknown. Therefore, the current study investigated the flotation behavior and surface properties of chalcopyrite after treatment with SMBS in the absence and presence of Ca(OH) 2 . The flotation experiments demonstrated that both SMBS treatment and the addition of Ca(OH) 2 exhibited a depressing effect on the natural floatability of chalcopyrite. This depressing effect of SMBS and Ca(OH) 2 on the floatability of chalcopyrite was significantly decreased in the presence of potassium amyl xanthate (PAX). However, the combination of SMBS treatment and Ca(OH) 2 formed calcium sulfite (CaSO 3 ) on the surface of chalcopyrite, which significantly reduced the recovery of chalcopyrite from 97% to 66% when in the presence of PAX and at a pH of 9. • The effect of Na 2 S 2 O 5 (SMBS) and Ca(OH) 2 on the floatability of chalcopyrite was studied. • Both SMBS and Ca(OH) 2 exhibited a depressing effect on the recovery of chalcopyrite. • SMBS produced sulfate and hydrophilic species on the surface of chalcopyrite. • SMBS and Ca(OH) 2 form CaSO 3 precipitate that reduced the recovery of chalcopyrite. • SMBS reduced the adsorbed PAX on the surface of chalcopyrite.

Impact of flotation operational parameters on the optimization of fine and coarse Itabirite iron ore beneficiation

This paper investigates the impact of operational parameters on the reverse flotation of Timbopeba itabirite iron ore in a pneumatic (MBE Pneuflot) flotation cell. To this end, the effects of physical and chemical parameters (i.e., collector and depressant dosage, superficial gas velocity (Jg), solids concentration, and feed rate) on the reverse flotation of iron ore are investigated in detail. Results show that increasing collector dosage increases quartz recovery, particularly for the coarser quartz where recovery increases by nearly 30%. Increasing depressant dosage results in a decrease in both quartz recovery and hematite loss, for the coarser hematite particles. In addition, increasing the feed rate does not affect quartz recovery or hematite loss, suggesting that the pneumatic flotation cell is not constrained by residence time. Furthermore, increasing the superficial gas velocity results in an increases in quartz recovery to an optimum at a Jg of around 0.6 cm/s after which it decreases significantly, particularly for the coarser particles where recovery decreases by 50%. Decreasing the solids concentration does not affect quartz recovery but results in a significant reduction in hematite loss. Here, fine and coarse hematite loss decrease from around 25% to 12% and 10% to 2%, respectively. Solids concentration and Jg are operating parameters that have the largest effect on the flotation performance of the pneumatic flotation cell. Overall, the obtained results suggest that this flotation cell should be operated at relatively low superficial gas velocities and solids concentrations. However, these findings are for a pilot scale and would need to be examined at larger scale (e.g., an industrial scale) where different operating conditions may be optimal.

Mechanism of Interaction between Morpholine Dithiocarbamate and Cyanoethyl Diethyldithiocarbamate Reagents and Low-Dimensional Gold on the Surface of Sulfide Minerals in Flotation of Difficult Gold-Bearing Ore

Mechanism of Interaction between Morpholine Dithiocarbamate and Cyanoethyl Diethyldithiocarbamate Reagents and Low-Dimensional Gold on the Surface of Sulfide Minerals in Flotation of Difficult Gold-Bearing Ore

Study on the flotation separation mechanism of diaspore from kaolinite using mixed NaOL/BHA collector

In this paper, oleate sodium (NaOL) and benzohydroxamic acid (BHA) was introduced as a mixed collector for diaspore ores. The flotation behavior and the adsorption mechanism of mixed NaOL/BHA collector to diaspore and kaolinite was investigated by flotation tests, FTIR spectra analysis, zeta potential analysis, surface tension analysis and foam performance tests. The flotation results demonstrated that compared to NaOL, mixed NaOL/BHA collector exhibited superior collecting property and selectivity to diaspore against kaolinite. In detailed, the recovery of kaolinite reduced by 20.01% and the aluminum–silicon ratio (A/S) increased by 9.42 in micro-flotation tests; the total recovery rate was increased from 86.42% to 90.85%, and the A/S was increased from 10.68 to 15.27 in bench-scale flotation of a bauxite ore. The FTIR spectra and zeta potential analysis shows that BHA can promote the adsorption of NaOL on diaspore, and inhibit the adsorption of NaOL on kaolinite. The mixed NaOL/BHA collector not only has a significant effect on mineral selective adsorption, but also affects the surface activity of gas–liquid interface and flotation foam characteristics, thus affecting the flotation separation of these two minerals. The addition of BHA ensures that NaOL has good foaming properties and at the same time makes the foam less sticky, which can reduce the gangue minerals entrained in the foam product and is beneficial to the subsequent treatment of foam products such as filtration and dehydration.