Flotation Of Spodumene Research Articles

The synergetic collecting effect of N-oleoyl sarcosine (N-OSS) and dodecylamine (DDA) on the selective flotation of spodumene from albite

In this study, N-OSS combined with DDA was examined as an novel collector. The collecting performances and their synergetic interaction mechanisms were investigated comprehensively. The micro-flotation results illustrated it exhibited excellent selectivity on separation without pre-activation. Contact angle tests revealed N-OSS/DDA could selectively enhance the hydrophobicity of spodumene, whereas, it barely affected that of albite. FTIR, SEM-EDS and Zeta potential revealed N-OSS/DDA might co-adsorb on spodumene surface rather than that of albite. XPS analysis and DFT calculations inferred the O1 2p orbitals of COO within N-OSS could bond with Al 3s orbitals and the NH3+ groups of DDA adsorbed onto the surface of spodumene via hydrogen bonding and electrostatic attraction. Meanwhile, the hydrogen bonding between N-OSS and DDA promoted the co-adsorption on spodumene surface. While N-OSS/DDA weakly adsorbed on the surface of albite through physical adsorption. N-OSS/DDA exhibited outstanding floatability, which maybe a good substitute for conventional collectors in future.

A new combined collector of sodium oleate and 1,12-dodecanediamine for efficient flotation separation of spodumene from feldspar

A new combined collector of NaOL and 1,12-Dodecanediamine (DA122) was used for efficient flotation of spodumene from feldspar. The disparities in mineral flotation efficacy between the combined collectors of NaOL/1,12-Dodecanediamine and NaOL/Dodecylamine (DDA), as well as the underlying mechanisms, were comprehensively analyzed by the measurements of flotation experiments, surface tension, adsorption amount measurement, structure and frontier molecular orbital analysis and adsorption model calculation. The results of mixed minerals micro-flotation indicate that the Li2O recovery of 91.64 % was achieved using NaOL and DA122 combined collector, which represents an 11.54 % increase in Li2O recovery compared to using the NaOL and DDA combined collector. NaOL and DA122 combined collector exhibits a lower critical micelle concentration (CMC) and the greater adsorption amount on the surface of spodumene. NaOL and DA122 combined collector demonstrates higher reactivity and adsorption energy on the surface of spodumene, resulting in higher hydrophobicity of spodumene because DA122 possesses stronger ability to lose electrons than DDA, thus leading to higher recovery of spodumene.

The evaluation of N-OSS (N-oleoyl sarcosine) as an efficient collector in the flotation of spodumene from albite at low temperature: Experimental tests and atom-level calculation

In this study, N-OSS was explored as an efficient collector in the flotation of spodumene from albite. The flotation behaviors were examined by micro-flotation tests and the interaction mechanisms were comprehensively uncovered from atomical scale. It indicated N-OSS could effectively collect spodumene from albite at low temperature and N-OSS was more inclined to adsorb on spodumene surface than that on albite surface, thus significantly expanding the hydrophobicity difference. X-ray photoelectron spectroscopy (XPS) analysis suggested that N-OSS chemically interacted with both Ca and Al active sites on Ca-activated spodumene surface. Whereas, it weakly adsorbed on Ca-activated albite. Density functional theory (DFT) calculations reconfirmed that the adsorption of N-OSS on Ca-activated spodumene surface was more favorable than that on albite surface. The strong adsorption on spodumene was due to the hybridization reaction between the O 2p orbitals of C-O and C=O groups of N-OSS with Ca 4s orbitals as well as Al 3s orbitals on spodumene surface. Nevertheless, N-OSS weakly interacted with Ca atoms on Ca-activated albite due to steric hindrance. N-OSS exhibited selective collecting ability at low temperature in the flotation of spodumene from albite compared with conventional collector, which has promising prospects in the low-temperature flotation of spodumene from albite.

Effects of Temperature on Spodumene Flotation and Gas–Liquid Interface of Sodium Oleate Solutions

This study investigates the negative impact of temperature on spodumene flotation from the perspective of the gas–liquid interface of sodium oleate (NaOL) solutions. Micro-flotation tests revealed a significant decrease in the flotation recovery of spodumene when NaOL was employed as a collector, dropping from 55.3% at 305.4 K to 5.1% at 277.3 K as the temperature decreased. A strong linear correlation between the surface tension of the NaOL solution and temperature was established. As the temperature decreased, the surface tension of 6 × 10−5 mol/L NaOL increased from 37.88 mN/m at 294.9 K to 40.71 mN/m at 281.9 K, while its critical micelle concentration decreased from 9.49 × 10−4 mol/L at 305.0 K to 6.85 × 10−4 mol/L at 288.0 K. Additionally, molecular dynamics (MD) simulations indicated that a decrease in temperature resulted in an enhancement of intermolecular action forces, a more compacted interfacial structure, and weakened molecular thermal motion at the gas–liquid interface of the NaOL solution. These variations were found to be the main reason for the rise in the surface tension of the NaOL solution as the temperature decreased, which in turn lowered its efficiency, resulting in a decrease in the flotation efficiency of spodumene.

The effect of conditioning pH behaviour on spodumene flotation with fatty acids

ABSTRACT Spodumene - the primary lithium mineral - is often concentrated by flotation with fatty acid collectors. However, producing high-grade concentrates at high recoveries is challenging and a risk for future operations. Poor spodumene selectivity is largely driven by the sensitive properties and poor solubility of fatty acids and requires high-density conditioning for desired flotation performance. This study related pH behaviour and operating parameters during fatty acid conditioning to flotation performance. The best pH characteristics for >85% lithium recovery at >5.25% Li2O were a minimum pH 6.5–6.8, final pH 6.7–7.1, and a pH change rate of 0.07 ΔpH/min. Regression analysis predicted optimizated conditions of initial pH 8.2, 30 W/L power density, 8 min conditioning and 550 g/t collector. Follow-up testing confirmed a higher W/L improved grade, and recovery was maintained when combined with decreased residence time and pH. Better defining these relationships can improve process control n developing industrial spodumene flotation circuits.

Effects of alkali pretreatment on the flotation of spodumene and feldspar

The surface chemistry and morphology of minerals produced by alkali pretreatment affects their flotation behaviors. This study systematically investigated the impact on the mineral surface dissolution using NaOH as a modifier, which could modify the surface properties of minerals and improve the floatability difference between spodumene and feldspar. Various characterizations including flotation experiments, flotation kinetics analysis, SEM analysis, microcalorimetry analysis, zeta potential measurements, XPS analysis and ICP-MS analysis were conducted. Single minerals and actual ore flotation experiment results were in good agreement, and the flotation grade and recovery of Li2O in spodumene concentrates increased by 1.11 % and 6.99 %, respectively, after NaOH pretreatment. The flotation kinetics results demonstrated the cumulative recoveries of spodumene exhibited the best agreement with the first-order kinetic model and the flotation kinetic constant was improved after alkali pretreatment. Microcalorimetric results indicated the absolute values of the reaction heat for spodumene were higher than that of feldspar reacted with collectors after the alkali pretreatment. XPS and ICP results demonstrated the amounts of Al active sites on the spodumene surface was significantly increased after alkali pretreatment compared to that on the feldspar surface, improving the selective adsorption of NaOL.

Molecular Design and Spodumene Flotation-A Review.

Spodumene flotation stands as the most commonly used method to concentrate lithium minerals. However, it faces significant challenges related to low collector recoveries and similarity in the surface characteristics of the minerals, which make the effective separation of this valuable mineral difficult. For this reason, numerous researchers have conducted studies to address and confront this problem. In this work, an exhaustive bibliographic search was carried out using keywords and search queries, and the results were structured in three sections according to temporal, methodological, and thematic criteria. The first section covers the period from 1950 to 2004, focusing on experimental tests. The second section covers from 2004 to the present and focuses on flotation tests and measurement analysis. Simultaneously, the third section spans from 2011 to the present and is based on molecular dynamics simulations. Topics covered include spodumene surface properties, the influence of metal ions, pre-treatment techniques, and the use of collectors. Ultimately, molecular dynamics simulations are positioned as a tool that accurately represents experimental phenomena. In this context, specialized software such as Materials Studio or Gromacs prove to be reliable instruments that allow a detailed study of mineral surfaces and other elements to be carried out, which justifies their consideration for future research in this scientific field.

Optimization of spodumene flotation with a fatty acid collector

An increasing demand for lithium-ion batteries is driving the development of new lithium mineral projects. Spodumene, a major lithium-bearing mineral found in pegmatite deposits, is often recovered by froth flotation. The primary collectors in spodumene flotation are fatty acids which are known for their poor selectivity. Fatty acid collectors tend to recover common gangue minerals in spodumene deposits due to their similar surface properties, making it difficult to produce high-grade concentrates with high lithium recovery. The ionic collector behavior is sensitive to pulp conditions like pH and concentration, but there is a weak understanding of this behavior during conditioning. There is a consensus that the conditioning stage is vital to flotation performance and should be conducted at high pulp-density (∼60% solids) to ensure proper collector adsorption. If not executed properly, rougher flotation suffers, making it challenging to achieve high final concentrate grades and recovery. This study uses a central composite experimental design and linear regression analysis to investigate and model the effects of four parameters of high-density conditioning with fatty acids on the responses of rougher concentrate grade and recovery: initial pulp pH, collector dosage, conditioning time, and power density. The models developed for both responses were determined to be statistically significant in the tested region. Initial pulp pH, collector dosage, and power density were significant terms in both models, while conditioning time was insignificant. Increased power density, ∼31 W/L, was necessary to achieve high rougher concentrate grades but increasing beyond 37 W/L was harmful to recovery. In general, higher collector dosages (>500 g/t) resulted in high recoveries, but initial pH must be adjusted accordingly to maintain concentrate grade. The most robust conditions to achieve > 90% recovery at a concentrate grade > 5.5% Li2O with this material were determined to be 31 W/L energy input and 625 g/t collector at an initial pH of 8.25. The flotation performance in this study is strongly connected to the behavior of fatty acid collectors reported in the literature and the findings provide good insight for operators and researchers aiming to improve spodumene flotation performance with fatty acids.

Mechanistic Study and Application of Anionic/Cationic Combination Collector ST-8 for the Flotation of Spodumene

The mechanism of anionic/cationic combination collector ST-8 for the efficient separation of spodumene and feldspar was investigated by flotation tests, surface tension measurements, zeta potential measurements and infrared spectroscopy analysis. The flotation results indicated that when the optimum molar ratio of sodium oleate and dodecylamine was 6:1–10:1 and pH = 8.5, the recovery of spodumene reached a maximum of 80% and that of feldspar reached about 24.5%. Zeta potential measurements showed that the negative shift of the kinetic potential on the surface of spodumene was much stronger than that on the surface of feldspar, indicating that the adsorption capacity of the combined collector on spodumene surface and feldspar surface was greatly different. From the surface tension as well as the synergistic parameters, there was a strong mutual attraction between dodecylamine and sodium oleate, and there was a significant synergistic effect between them. Infrared spectroscopy indicated that the combined collector chemisorbed on the mineral surface, and the intensity of the absorption peak after the action of spodumene was much stronger than that after the action of feldspar. The solution chemistry of the combined collector revealed that at pH 8.5, the positively charged ions RNH3+ and (RNH3+)22+ in dodecylamine and the negatively charged RCOO− and (RCOO−)22− ions in oleic acid form highly reactive complexes to interact with the mineral surface by electrostatic gravitation, thus achieving efficient separation of spodumene and feldspar. Finally, from the closed-circuit test results, a flotation index of 6.34% Li2O grade and 88.51% Li2O recovery was obtained.

The selective adsorption and flotation separation of spodumene from feldspar using a novel iron-group multiple ligand collector

Spodumene and feldspar have little difference in flotability due to their similar crystal chemistry properties. Fe-octyl hydroxamic acid (OHA) (iron complexes of octyl hydroxamic acid) demonstrates excellent selectivity but restricted collecting performance in spodumene flotation. In this work, we added sodium dodecyl sulfate (SDS) into Fe-OHA to obtain a novel multiple ligand collector, which was named Fe-OHA-SDS to enhance the collection ability of Fe-OHA. The efficient separation of spodumene from feldspar (the recovery difference was about 84 %) was achieved by Fe-OHA-SDS without adding depressants and foaming agents at pH 6.2. The separation mechanisms were explored by Zeta potential, contact angle, in-situ microcalorimetric, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) measurements. The findings revealed that Fe-OHA-SDS was more easily bonded to the spodumene surface than the feldspar surface. Meanwhile, the adsorption of Fe-OHA-SDS significantly expanded the hydrophobicity differences on these two mineral surfaces. The Fe-OHA-SDS was adsorbed on the spodumene surface through the Fe-O bond, which differed from the interaction mechanism of traditional mixed collectors on mineral surfaces. Therefore, Fe-OHA-SDS was an efficient collector with potential application value in spodumene flotation.

Geochemistry and mineralogy of a spodumene-pegmatite lithium ore at various mineral beneficiation stages

Spodumene is currently the main source of lithium (Li), and Li release in mine waters stands out as a common feature of the otherwise scarcely studied spodumene mine tailings. In order to study how mineral beneficiation affects the geochemical behavior of a pegmatitic spodumene ore and the quality of its drainage, materials from the Whabouchi mine project (Québec, Canada) were submitted to advanced mineralogical characterization and kinetic testing in columns and weathering cells. Materials were sampled at various pilot processing steps, from raw ore to concentrator feed and tailings from dense medium separation and spodumene flotation. Processing did not modify markedly the chemical composition of the minerals and the mineralogical assemblage, except the spodumene content. Besides the major quartz, feldspars, spodumene, and muscovite, many accessory minerals were identified including Nb-Ta oxides and U-bearing minerals. Kinetic testing results indicate that all the studied materials produce neutral to slightly alkaline leachates (pH 7–8). Generally, elemental concentrations decrease rapidly over the first few flushes, are higher in columns than in weathering cells, and are higher for finer-grained processed materials. Elemental mobility is not necessarily proportional to bulk-rock abundance and liquid-to-solid ratio, overall following the order Ca (10 s of mg/L) > Na, K (10 s of mg/L to sub-mg/L) > Li, U (mg to sub-mg/L) > Mn, Fe, Al (sub-mg/L). Uranium mobility seems linked to scattered Ca-uranyl-(Si or P)-bearing voids and fracture-filling soluble minerals rather than primary uraninite, and Ca-uranyl-carbonate complexation is suggested as a promoting factor. Thermodynamic equilibrium calculations only identify clay minerals and metal (hydr)oxides as possible secondary minerals; formation of Al and Fe colloids is experimentally evidenced. Specific surface area and rinsing volume-normalized release rates, however, highlight effects of both processing and the testing protocol on the reactivity of the studied materials. The most processed material studied, flotation tailings, consistently produced the lowest normalized release rates for all the elements surveyed, while the most aggressive testing protocol (weathering cells, with frequent flushes at a high liquid-to-solid ratio) always yielded the highest normalized release rates. This laboratory-scale study outlines how mineralogy (both major and trace), processing, and testing protocol, affect the geochemical behavior of pegmatitic spodumene ore and tailings.

Effects of dissolution by alkali treatment on anisotropic surface properties and flotation behavior of spodumene

The effect of dissolution pretreatment of spodumene using NaOH and Na2CO3 was investigated by micro-flotation test, contact angle measurement, XPS, ICP and AFM imaging. The results showed that NaOH treatment activated the spodumene flotation whilst Na2CO3 showed little depression effect. NaOH had more significant activating effect on the spodumene (001) surface than (110) surface. The surface dissolution was confirmed by AFM, showing that weak surface dissolution was observed in ultrapure water and Na2CO3 solution, while there was strong surface dissolution in NaOH solution. Some precipitates coated the surface at the very start in NaOH and Na2CO3 solution, and the precipitates redissolved rapidly in NaOH solution while redissolved very slowly in Na2CO3 solution. The ICP results verified the release of Si, Al and Li from spodumene surface. NaOH treatment gave larger relative contents of Al on spodumene surface than Na2CO3, and the relative contents of Al on the (001) surface increased to a greater extent than on the (110) surface, as revealed by XPS analysis. From the point of crystal structure, the dissolution made more dangling Al exposed on the (001) surface, making it more favor of NaOL adsorption.

Ultrasound application in alkaline pretreatment process of spodumene to improve particle floatability

Selective surface dissolution was found to be important in spodumene flotation. In this study, we proposed to introduce ultrasound into the pretreatment process to accelerate particle vibration and cavitation, as well as the migration of mineral surface components to solution. Micro-flotation results showed that the flotation recovery of spodumene can be 86.08% by ultrasound pretreatment, but only 39.30% by traditional mechanical agitation pretreatment. Compared with traditional mechanical agitation, ultrasonic pretreatment can shorten the pretreatment process, reduce the dosage of agents, reduce the mechanical agitation speed, and improve the efficiency of the pretreating process. Inductively coupled plasma analysis showed that, in the ultrasonic system, the amount of Li, Al, and Si species in the solution was twice as much as those in the traditional preprocessing system. Moreover, the scanning electron microscope results demonstrated a larger surface dissolution area in the ultrasonic system. X-Ray photoelectron spectroscopy results showed that the atomic concentration of Si species on the spodumene surface decreased, whereas the relative atomic concentrations of Li and Al species increased, indicating that the ultrasound effect strengthened the selective dissolution of elements on the mineral surface. The high-resolution spectra of O 1s showed that more collectors are adsorbed on the mineral surface treated by ultrasonic pretreatment.

Enhanced flotation separation of spodumene and albite via selective adsorption of N-hydroxy-9-octadecenamide on the mineral surfaces

Spodumene (LiAl(SiO3)2) is an important Li-bearing mineral from which Li is extracted economically. Flotation is an important method for separating spodumene from its associated gangue minerals such as albite. Oleic acid is a traditional collector utilized in the flotation separation of spodumene/albite; however, it has limited selectivity. To address this, N-hydroxy-9-octadecenamide (N-OH-9-ODA) is developed by transforming the carboxyl group, the polar group of oleic acid, into the N-hydroxy amide group. A comparative investigation of N-OH-9-ODA and oleic acid in the flotation separation of spodumene/albite is conducted through flotation experiments. The findings of the flotation experiments indicate that N-OH-9-ODA exhibits better selectivity and stronger collecting ability than oleic acid. N-OH-9-ODA has a stronger affinity for spodumene than albite, which is reflected by a more significant shift in the zeta potential of spodumene particles compared to albite particles caused by the additions of N-OH-9-ODA. The flotation experiments also show that the prior addition of Ca2+ ions can enhance the ability of N-OH-9-ODA to collect spodumene particles. The activation of Ca2+ ions for the N-OH-9-ODA flotation of spodumene is due to the stronger reactivity of Ca2+ ions adsorbed on spodumene surface for the N-OH-9-ODA adsorption compared to Al3+ ions of pure spodumene surface, which is demonstrated by a higher adsorption energy of N-OH-9-ODA on the Ca2+-activated spodumene surface than that on pure spodumene surface.

A Review of Fatty Acid Collectors: Implications for Spodumene Flotation

Increasing demand for lithium-ion batteries has led to the development of several new lithium mineral projects around the globe. Some major mineral processing challenges these projects face are similarities in gangue and value mineral behaviour and poor selectivity in froth flotation. Unsaturated anionic fatty acids are the primary spodumene flotation collectors, known to be strong collectors with poor solubility and selectivity. Fundamental flotation research consensus is that spodumene flotation is driven by a fatty acid–anion complex adsorbed at cationic aluminum sites. However, many small-scale studies result in poor recoveries, prompting several researchers to investigate cationic activators or mixed anionic/cationic collectors to improve flotation performance. Testwork with real spodumene ore is rare in recent literature, but older publications from several deposits prove that fatty acids can successfully concentrate spodumene. The process generally includes alkaline scrubbing, high-density fatty acid conditioning, and flotation at pH 7.5–8.5 with 500–750 g/t fatty acid collector. The collector speciation behaviour is notably sensitive to pulp conditions around this pH; possibly resulting in unstable flotation circuits and inconsistent results. This paper reviews fatty acid collector properties and the available industrial and fundamental spodumene flotation research. We aim to provide new insight for understanding particle-collector interactions in spodumene flotation and help bridge the gap between fundamental and industrial processes which will be needed to de-risk projects in the growing lithium mineral industry.

Effects of Spodumene Flotation Tailings on Mechanical Properties of Acid-Based Geopolymer Mortar

This study focuses on using spodumene flotation tailings (SFT) to prepare phosphoric acid-activated metakaolin geopolymer, in which the replacement of metakaolin (MK) by a high percentage (up to 75 wt.%) of tailings was achieved. The compressive strength of geopolymer mortar was significantly improved with SFT as aggregates. In addition, the mechanical properties could also be enhanced by an increased concentration of phosphoric acid (H3PO4) solution or a decreased aggregate particle size. The optimized geopolymer mortar composite was SFT:MK = 3:1, which was activated by H3PO4 solution with a concentration of 51 vol%, followed by curing at 55 °C for 24 h. On the other hand, properties of the geopolymer mortar could also be affected by the morphology of the aggregates. For example, SFT as aggregates could produce more interconnected pores compared to standard sand. The major chemical structural units of geopolymer mortar were -P-O-Al- and AlPO4, which could be spontaneously generated according to the thermodynamic calculation results. Finally, many aluminum ions and a small amount of silicon ions could be leached from the tailings under acidic conditions.

Flotation performance of calcined spodumene

Spodumene flotation in the presence of oleate is widely used in the lithium mining industry. However, there is no study investigating flotation behaviour of calcined spodumene. Thus, the main focus of this technical note is to address this matter. The results showed that the increase in the calcination temperature led to fractured spodumene surfaces as found using MLA (mineral liberation analyser), probably resulting in higher oleate adsorption on spodumene surfaces. Another reason for higher oleate adsorption on calcined samples could be due to the changes in surface properties of calcined spodumene (i.e. α to β transformation of spodumene). Therefore, the higher the calcination temperature, the higher the flotation recovery of calcined spodumene. This work shows that calcination before flotation can be highly beneficial pre-treatment for improving the lithium recoveries and grades.

Is spodumene flotation tailings suitable for the preparation of ceramics?

In this paper, an investigation was conducted on the effects arising from albite, K-feldspar, quartz (three particle sizes) and muscovite (two particle sizes) of spodumene flotation tailings on ceramics, as well as the corresponding crystal changes. As indicated by the results, albite and K-feldspar positively impacted the strength of ceramic materials. The flexural strength of ceramics was increased with the decrease in the particle size of quartz. The flexural strength and linear shrinkage of ceramic materials was increased with decreased particle size of muscovite. The melting of albite and the formation of eutectic phase from albite and quart filled the pores between mineral particles, which were found as the major sintering mechanism of ceramics. Furthermore, during the sintering process, the crystal phase transformation of α-quartz to β-quartz and the de-hydroxylation of muscovite and kaolinite was occurred. Lastly, tailings have the potential to be used as raw materials for ceramic materials. Quartz could be used as ridge materials and green materials for permeable ceramics, albite could be used as flux for low temperature sintered ceramics, and muscovite could be used to prepare mullite refractories.

The activation mechanism of metal ions on spodumene flotation from the perspective of in situ ATR-FTIR and ToF-SIMS

• Fe 3+ , Mg 2+ , and Ca 2+ exhibited strong activation ability for the spodumene flotation . • The activation ability of Ca 2+ and Mg 2+ to spodumene is stronger than that of Fe 3+ . • The metal ions provided more active sites for the adsorption of NaOL. • The colloidal complexes of metal ions and NaOL strengthened the spodumene flotation. The existence of metal ions is inevitable in the spodumene ore beneficiation and the study of their interaction mechanism with spodumene is of great significance for the spodumene flotation. In this work, the effect of Fe 3+ , Mg 2+ , and Ca 2+ on the flotation behavior of spodumene with NaOL was investigated through micro-flotation experiments. The flotation results showed that Fe 3+ , Mg 2+ , and Ca 2+ exhibited strong activation ability at pH 6.5, 10.9, and 12.1, respectively, and the activation ability of Mg 2+ and Ca 2+ toward spodumene was superior compared to that of Fe 3+ . The activation mechanism of metal ions was explored by the Visual MINTEQ model, in-situ attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results of species distribution calculated by the Visual MINTEQ model and in situ ATR-FTIR demonstrated that NaOL adsorbed more strongly onto spodumene in the presence of Mg 2+ and Ca 2+ compared with that of Fe 3+ , resulting in better activation of Mg 2+ and Ca 2+ . In addition, XPS and ToF-SIMS analyses revealed that the activation of spodumene by metal ions works in two ways. It not only provides more active sites for the adsorption of NaOL, but also interacts with NaOL to form the colloidal complexes and then adsorbed on the spodumene surface.

Effects of spodumene flotation tailings as aggregates on mechanical properties of cement mortar

This work explored the use of spodumene flotation tailings (SFT) as an aggregate used in cement mortar to mitigate their environmental impact. The principal phase compositions of SFT were quartz (Qtz), feldspar (Fsp) and muscovite (Ms). So, the effects of variations in the particle size of Qtz, and mineral additives, Ms and Fsp, on the compressive strength and hydration products were examined. Ms additives imparted the lowest compressive strength. Finer Qtz aggregates (4000–106 µm) reduced the nano-pore volume, and Ms increased the nano-pore width of cement mortar. In addition, fewer hydration products, and poor crystallinity of both ettringite (Aft) and portlandite resulted in a decrease in the compressive strength of the cement mortar, eventually. Therefore, increasing the particle size or optimisation of the mineral composition of SFT could provide a facile route to improving the mechanical properties of cement mortars.