Flotation Separation Of Quartz Research Articles

Application of novel ionic liquids in flotation separation of quartz and magnesite and its mechanism

Application of a novel ionic liquid as flotation reagent in the flotation separation of quartz and magnesite has been investigated. The flotation behavior and surface properties of quartz and magnesite flotation with dodecyl trimethyl ammonium-diethylphosphonic acid (N12111-DEPA) as flotation reagent were studied by microbubble flotation experiments, contact angle, fourier transforming infrared spectra (FT-IR), and X ray photoelectron spectroscopy (XPS) spectrometer analysis. The micro-flotation of single mineral results demonstrated that N12111-DEPA exhibited a good collection selectivity for quartz. Under the optimum flotation conditions of pulp pH 7.0 and 15 mg/L N12111-DEPA, the grade and recovery of MgO in concentrate were 41.21 % and 97.45 %, respectively. The analysis of contact angle shown that N12111-DEPA increased the surface hydrophobicity of quartz and decreases the surface hydrophobicity of magnesite, thus increasing the difference of floatability between the two minerals. The analysis of FT-IR and XPS confirmed that the cations of N12111-DEPA are mainly adsorbed on quartz surface through electrostatic affinity, while the anions of N12111-DEPA are mainly adsorbed on magnesite surface through chelation with exposed magnesium sites on mineral surface. This demonstrated that N12111-DEPA had a good application potential in reverse flotation separation of magnesite and quartz.

Flotation separation of hematite from quartz with dodecyl trimethyl ammonium chloride and sodium dodecyl sulfonate collector

Through a series of testing methods, including micro-flotation tests, contact angle test, ζ-potential analysis, FTIR, and XPS, the behavior and mechanism of flotation separation of hematite and quartz by mixed anionic-cationic collectors (Dodecyl Trimethyl Ammonium Chloride (DTAC) and Sodium Dodecyl Sulfonate (SDS), DS for short) were investigated. Additionally, the froth performance of the mixed collector was examined through froth stability experiments. The study revealed that the inclusion of DS collectors significantly enhanced the flotation separation efficiency of quartz-hematite, with the addition of SDS leading to a reduction in the foam viscosity of DTAC. Notably, at a pH of 7 and with a DTAC to SDS mass ratio of 2:1, the mixed collector demonstrated exceptional performance in the flotation separation of quartz and hematite, achieving a quartz recovery of 91.85 % and a hematite recovery of 11.45 %. This efficacy was corroborated by ζ-potential measurements, FT-IR analysis, and XPS analysis, which confirmed the physical adsorption of DS on the mineral surfaces. Importantly, the adsorption dynamics were found to be influenced by the different surface charge characteristics of quartz and hematite. Specifically, the higher negative charge on the surface of quartz resulted in unaffected DTAC adsorption in the presence of SDS, while on hematite surfaces, the DTAC interaction with SDS led to the partial desorption of DTAC. Consequently, the adsorption of DTAC on hematite surfaces was reduced, facilitating the selective separation of quartz and hematite.

Atomic insight into the activation mechanism of feldspar by sodium oleate in flotation separation of quartz and feldspar: XPS, AFM, and molecular dynamics

ABSTRACT As we all know, sodium oleate (NaOL) is usually used as a collector for oxidized minerals, but in this study, it is used as an activator for feldspar to separate from quartz. Therefore, the adsorption mechanism, topography, and configurations of NaOL on the quartz and feldspar surface were investigated using X-ray photoelectron spectroscopy, atomic force microscope, and molecular dynamics simulation at the atomic level. The results revealed that NaOL preferably interacted with the Al atoms on the feldspar surface mostly in the form of chemical adsorption and made the feldspar surface blurry and rough, so NaOL could activate feldspar and enhance its flotability. However, NaOL hardly reacts or is easily desorbed from the quartz surface. Thus, the adsorption differences of NaOL between the quartz and feldspar surfaces contributed to realize the effective separation of quartz and feldspar.

Adsorption mechanisms of activated surface of quartz and feldspar with mixed NaOL/DDA

In this paper, the flotation separation of quartz and feldspar was studied with CaCl2 as activators and mixed sodium oleate/ dodecylamine (NaOL/DDA) collectors under alkaline condition, and the action mechanism of mixed NaOL/DDA collectors on the quartz and feldspar surfaces were systematically explored. The results of micro-flotation test showed that there were 90.98% quartz and 13.08% feldspar were floated with 0.5 mmol/L CaCl2 and 2.8 mmol/L mixed NaOL/DDA collectors with molar ratio of 8/1 at pH 10.0. And the artificial mixed minerals flotation manifested these two minerals were able to efficient separation with CaCl2 and mixed NaOL/DDA collectors at pH 10 ∼ 11. These outcomes indicated that DDA could increase recovery of quartz obviously and reduce about a half dosage of NaOL (from 0.5 mmol/L to 0.25 mmol/L) in flotation under alkaline condition; Meanwhile, mixed NaOL/DDA collectors were able to decreased the flotation separation pH from 12 to 10 on quartz and feldspar. Infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results revealed that when NaOL collector was added alone, it could adsorb on activated quartz surface but hardly detected on feldspar surface at pH 10. However, they all were found on both quartz and felspar surface when mixed NaOL/DDA collectors were introduced as collectors. Quartz microcrystal balance with dissipation (QCM-D) experiment confirmed that mixed NaOL/DDA collectors showed a higher adsorption mass and more stable adsorption layer on quartz compared with NaOL was introduced as collector alone. In addition, whether CaCl2, NaOL or mixed NaOL/DDA, the adsorption mass on quartz sensor were larger than that on feldspar senor, which might cause difference of hydrophobicity on the surface of quartz and feldspar in flotation. The above experiments showed that the mixed NaOL/DDA collectors can significantly improve hydrophobic difference between quartz and feldspar after activating with CaCl2 and expand the floated pH range of quartz compared with using NaOL as collector alone, which were efficient reagents to separate quartz and feldspar in flotation.

Selective flotation of quartz from feldspar using hydroxypropyl starch as depressant

Feldspar and quartz are similar in composition and structure, and hence, they exhibit low flotation separation efficiency in acid or alkaline conditions and while using the traditional reagents scheme. In this study, hydroxypropyl starch (HPS) was introduced as a novel depressant in the flotation separation of quartz from feldspar. Magnesium chloride (MgCl2) was used as an activator and sodium oleate (NaOL) as a collector. The micro-flotation tests showed that the pulp pH had a decisive influence on the flotation separation of quartz from feldspar. At pH 10.50, quartz and feldspar could be partially separated without depressants. However, some amount of feldspar (10%-20%) remained afloat, resulting in a low quartz grade in the concentrate. The flotation of feldspar was selectively depressed using HPS as depressant, leading to a much higher separation efficiency, and the selectivity index increased from 4.57 to 7.52. The high selective performance of HPS depressant was also confirmed via the bench-scale flotation tests, and the yield of the feldspar products increased from 22.70% to 30.20%, while the grade of K2O + Na2O increased from 13.73% to 14.35%. The inhibitory mechanisms of feldspar and quartz were analyzed through Raman and X-ray photoelectron spectroscopy. These results indicated that HPS leaned towards complex formations with Al-sites on the surface of feldspar, thereby reducing the adsorption of NaOL and inhibiting the flotation of feldspar. Therefore, HPS could be used as a feldspar depressant in flotation separation quartz from feldspar.

Novel polyhydroxy cationic collector N-(2,3-propanediol)-N-dodecylamine: Synthesis and flotation performance to hematite and quartz

To enhance the performance of traditional cationic collector, a novel polyhydroxy amine collector N-(2,3-Propanediol)-N-dodecylamine (PDDA) was designed by introducing one propylene glycol group into dodecylamine (DDA). It was prepared by a nucleophilic substitution reaction, which showed better solubility and hydrophobicity than DDA and was firstly employed as the collector for the separation of hematite and quartz. Flotation tests showed that PDDA had an excellent flotation performance and significantly better selectivity than DDA. In addition, the flotation performance and adsorption mechanism of PDDA on hematite and quartz surfaces were studied using Fourier transform infrared spectroscopy (FT-IR), zeta potential and X-ray photoelectron spectroscopy (XPS) tests. These results demonstrated that the interaction between PDDA and the minerals’ surfaces was mainly electrostatic adsorption and hydrogen bond, while PDDA tended to adsorb on the surfaces of quartz more than that of hematite. Performance optimization of amine collectors by introducing hydroxyl was also verified, which was of great meaning to the design, development, and application of the polyhydroxy cationic collector. In conclusion, PDDA could be used as a potential collector in the flotation separation of quartz and hematite.

Flotation separation of quartz and dolomite from collophane using sodium N-dodecyl-β-amino propionate and its adsorption mechanism

Flotation is the most widely used method to effectively separate dolomite and quartz from collophane. Conventional amine collectors can’t effectively remove silicate minerals due to their poor selectivity, thick foam and weak collective performance. In this work, a novel amphoteric collector sodium N-dodecyl-β-amino propionate(C12Giy) was synthesized by methyl acrylate method. The strength of C12Giy's collective performance for three minerals was investigated by the micro-flotation test. In addition, the adsorption mechanism of C12Giy on the surface of three minerals was studied by zeta potential test, infrared spectroscopy and XPS test. The micro-flotation results show that C12Giy has a strong collection performance for dolomite and quartz, but weaker for collophane. It was also noted that when the pH is 3 and the concentration of C12Giy is 30 mg/L, collophane and quartz can be effectively separated. Similarly, when the pH is 5 and the C12Giy concentration is 30 mg/L, the effective separation of collophane and dolomite can be achieved. Zeta potential test and infrared spectrum analysis showed that C12Giy was adsorbed on surface of collophane and quartz by electrostatic attraction at pH= 3, while it is chemical adsorption on the surface of dolomite at pH= 5. The XPS analysis further indicated that the exposed magnesium ions on the surface of dolomite are crucial for the selective adsorption of C12Giy on dolomite. On the one hand, Magnesium ions, as an important component on the surface of dolomite rather than collophane, enhance the chemical adsorption of C12Giy on dolomite. On the other hand, it increases the total interaction energy of dolomite with quartz particles by adding C12Giy, which in turn increases their electrostatic attraction with the bubbles. Therefore, C12Giy can be utilized as a potential collector to separate dolomite and quartz from collophane.

Flotation separation of quartz from phosphorite using an imidazole ionic liquid collector and its adsorption mechanism

Flotation separation of quartz from phosphorite using an imidazole ionic liquid collector and its adsorption mechanism

Potential application of an eco-friendly amine oxide collector in flotation separation of quartz from hematite

The development of eco-friendly collectors is an essential issue of much concern in mineral flotation processes. In this work, an eco-friendly amine oxide, N,N-Dimethyl aminopropyl dodecylamide oxide (LAO), was introduced as the collector in flotation separation of hematite and quartz. Compared with conventional amine collector dodecylamine (DDA), LAO with low toxicity has better flotation performance and superior selectivity in the natural slurry. With 10 mg/L LAO, the recovery of quartz and hematite is respectively 94.72% and 10.50%, while using the same dosage of DDA, the quartz recovery is only around 40% and the hematite recovery is 23%. The median effective inhibition concentration (EC50) of LAO for Daphnia magna is 328.44 mg/L, indicating LAO is a nontoxic compound to aquatic organisms. Therefore, LAO is a promising eco-friendly collector to apply in the separation of quartz from hematite.

Flotation separation of quartz from gypsum using benzyl quaternary ammonium salt as collector

Phosphogypsum is a kind of industrial by-product, which could be used as building materials instead of natural gypsum after removing impurities. Flotation is an effective method to remove the silicon-containing impurity quartz in the phosphogypsum. In this work, a surfactant tetradecyl dimethyl benzyl ammonium chloride (TDBAC) was first used as the collector of quartz to be separated from gypsum. The flotation behaviors of quartz and gypsum were investigated by micro-flotation experiments. The flotation mechanisms were analyzed through Zeta potential testing, Fourier Transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Micro-flotation results show that TDBAC exhibited outstanding collecting capacity and selectivity for quartz over the wide pH range of 2.5–9.5. FTIR results declared that TDBAC could be successfully adsorbed on the surface quartz. The analysis results of zeta potential and XPS indicate that the interaction mechanisms of TDBAC with quartz were involved electrostatic attraction and hydrogen-bond interaction, whereas the adsorption onto gypsum surface was only by the weak electrostatic attraction and hydrogen-bond interaction. The results of this work showed that TDBAC is expected to be an effective collector of quartz for removing silicon impurity from the industrial phosphogypsum.

Synergistic Effect of DBP with CTAB on Flotation Separation of Quartz from Collophane

Collophane is difficult to upgrade by reverse flotation of quartz with amine collector alone due to its low grade, complex structure, fine dissemination grain size, etc. This investigation was conducted to explore the synergistic effect of dibutyl phthalate (DBP) as a surfactant with cetyltrimethyl ammonium bromide (CTAB) as the collector on the separation of quartz from collophane by means of micro-flotation tests, surface tension and aggregate size measurements, and froth water mass fraction/recovery characterization. It was found that DBP reduced the surface tension of the reagent solution and enhanced the collision probability between bubbles and quartz particles by increasing the size of aggregates through increased hydrophobic interaction between the quartz particles and DBP droplets. The addition of DBP reduced the entrainment of fine collophane particles as a result of improved defoaming and increased the flotation recovery of quartz without resulting in any flotation of collophane at dosages lower than 200 mg/L. Flotation test results with the binary artificial mineral mixture showed that DBP improved the P2O5 recovery, SiO2 rejection, and P2O5 grade by up to 7%, 12%, and 1%, respectively.

Flotation separation of quartz from apatite and surface forces in bubble–particle interactions: Role of pH and cationic amine collector contents

Dodecylamine hydrochloride (DAHC) surfactant was used as a collector for effective apatite recovery through flotation separation in siliceous phosphate ore, wherein quartz is the main gangue mineral. The roles of pH and collector concentration were investigated, and the adsorption of the collector on the minerals and related properties were systematically studied by measuring zeta potential, contact angle, surface tension, and adsorption density. When the collector concentration was 5×10−5M, 23.7% P2O5 grade was achieved for a conditioning time of 10min. However, the separation performance of the flotation was lower at pH 7 regardless of the collector concentration. Thus, more collector molecules are adsorbed on the quartz surface than the apatite surface at pH 3 and 5×10−5M of collector, resulting in separation of quartz and apatite. The extended Derjaguin–Landau–Verwey–Overbeek (DLVO) theory, which considers the hydrophobic interaction energy, revealed that the improved flotation performance is attributed to a hydrophobic attractive force that is a consequence of the collector adsorption. Therefore, the results of flotation of artificially mixed minerals further revealed that optimization of the amine collector concentration and pH value can selectively separate quartz from apatite.

Dissolution of starch and its role in the flotation separation of quartz from hematite

Corn starches are cheap and eco-friendly flotation depressants for iron oxides, but their solubilities in water at ambient temperature are low. Starches are often treated by alkali or thermal gelatinization to enhance their dissolution before being used in iron ore flotation. Despite its importance, little is known about the fundamentals of starch dissolution and its role in iron ore flotation. In this paper, four corn starches (waxy, normal, G50 and G80) differing in the mass ratio of amylopectin to amylose were used to investigate the starch solubility as a function of solution preparation temperature and pH. It was found that the starch solubility increased with increasing the solution preparation temperature, pH, or the mass ratio of amylopectin to amylose. Three stages of starch dissolution (swelling – rupturing – releasing starch molecules/ghost) were observed, and the tendency for the rupturing followed the order of waxy starch>normal starch>G50>G80, indicating that a starch with higher amylopectin content could be more readily dissolved. Micro-flotation tests were carried out for pure hematite and quartz and their mixture with these four starches dissolved at different temperatures and pHs. The results suggest that there is a strong correlation between starch solubility and the depressing ability. Among these starches tested, waxy starch and normal starch, which have relatively high amylopectin contents, are preferred for being used in the flotation separation of quartz from hematite as depressant after proper solution preparation.

Flotation separation of quartz from collophane using an amine collector and its adsorption mechanisms

Quartz is the dominant gangue mineral in siliceous phosphate ore. To obtain efficient concentration of phosphate minerals, the flotation separation of quartz and collophane using AY as a collector was studied in this paper. The adsorption mechanism of the collector on the surface of quartz and collophane were investigated by measuring zeta potential, contact angle, adsorption density, surface tension and analyzing FTIR spectra. It reveals that AY displays a stronger collecting ability for quartz relative to collophane at pulp pH7, resulting in a separation window for the two minerals. When the dosage of collector was 50mg/L, phosphate minerals could be concentrated from 23.96% to 30.18% P2O5 with a great recovery of 98.24%. Mechanism studies show that the interaction of the amine collector with quartz and with collophane is mainly through electrostatic attraction, whereas the cationic collector prefers adsorbing on the negatively charged quartz. This is also supported by measurement of minerals contact angle and collector's adsorption density. AY as a collector has a selective absorption on quartz rather than collophane.

Effect of butanol on flotation separation of quartz from hematite with N-dodecyl ethylenediamine

In order to investigate the effect of butanol on quartz flotation when N-dodecyl ethylenediamine (ND) was used as collector, single mineral flotation and artificial mixed mineral (hematite and quartz were mixed at a mass ratio of 3:2) separation were conducted in the laboratory. Experimental results indicated that addition of butanol could improve the collecting performance of ND on quartz and enhance the floatability of quartz. Best flotation recovery of quartz was obtained when butanol was mixed with ND at a mass ratio of 1:1. Moreover, the molecular structure of alcohols had a significant effect on mineral recovery. Best separation efficiency could be obtained when tert-butanol was added as it had the largest cross-sectional area. Zeta potential measurements indicated that alcohols could strengthen electrostatic adsorption between quartz and collector. Molecular dynamic simulations revealed that co-adsorption of alcohols along with ND had taken place on the quartz surface, and ND/tert-butyl combinations were more easily absorbed on the quartz surface.

Aliquat-336 as a novel collector for quartz flotation

The study illustrates the first ever use of Aliquat-336 (C25H54ClN), an ionic liquid, in the flotation separation of quartz from hematite. Laboratory flotation studies of hematite, quartz and their synthetic mixture have shown selective collecting action of Aliquat-336 toward quartz. At an Aliquat-336 dosage of 280g/t, 97% quartz is floated at slightly alkaline pH (∼8), whereas hematite recovery is only 8%. Flotation of the synthetic mixture of hematite: quartz (1:1), with Aliquat-336 as the quartz collector and starch as the hematite depressant, has resulted in an iron concentrate of 63–65% Fe with 85–88% recovery. The reverse flotation behavior of the low grade banded hematite quartzite (BHQ) using Aliquat-336 as the collector has been investigated. It is observed that, iron values up to ∼65% Fe with 60% recovery can be achieved from the ore containing ∼38% Fe. Surface potential measurement and FTIR spectra lead to the indication of electrostatic adsorption between Aliquat-336 and quartz.

The flotation of quartz from iron minerals with a combined quaternary ammonium salt

A combined quaternary ammonium salt was used as a collector for the flotation of quartz. It shows better selectivity and collectability than dodecyl amine chloride and cetyl trimethylammonium bromide for the flotation of quartz from magnetite and specularite, but the quebracho should be used in the flotation separation of quartz from specularite. By the measurement of zeta potentials, contact angles, and adsorption of the combined quaternary ammonium salt, the results show that the combined quaternary ammonium salt is preferred to adsorb on the surface of quartz, changes its zeta potentials and contact angles, and increases its hydrophobicity. The results of FTIR show that the combined quaternary ammonium salt adsorbs on the quartz surface in physical adsorption with no new products.