Ion-adsorption Type Rare Earth Research Articles

Bioleaching ion-unexchangeable rare earth in ion-adsorption type rare earth waste tailing

Ion-adsorption type rare earth ores (IREO) in China serve as the primary source of medium and heavy rare earth globally. With the rapidly growing demand for rare earth elements (REEs) and the dwindling supply of premium IREO, enhancing the recovery of REEs, especially the ion-unexchangeable REEs with ultra-low content and ambiguous speciation from IREO or its tailing, has become a critical trend and challenge. This study identified the occurrences of ion-unexchangeable REEs, primarily detected in Fe-enriched minerals, xenotime, and monazite of IREO using TESCAN integrated mineral analyzer (TIMA) and laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) analysis. To extract these elusive REEs, a bioleaching technique utilizing Aspergillus niger (A. niger) metabolites was proposed, achieving a leaching yield of 31.4 wt%. Complementary sequential chemical extraction methods (SCEM), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations further elucidate the underlying mechanism, involving the carboxylic acid produced by the metabolic process of microbes that dissolves goethite by disrupting FeO bonds and liberating REEs, which complexed with carboxylate (RCOO), to promote further dissolution. This work offers insight into enhancing the recovery of ion-unexchangeable REEs from IREO or its tailing, paving the way for sustainable and efficient rare earth mining practices.

Impacts of Ion Adsorption Type Rare Earth Mining Techniques on Topsoil in Mining Area

Impacts of Ion Adsorption Type Rare Earth Mining Techniques on Topsoil in Mining Area

Desorption behavior and mechanism of yttrium ions from ion-adsorption type rare earths ore

Ion-adsorption type rare earths ore (IREO) is an important strategic resource that can be leached in-situ using electrolytes such as NH4+, Mg2+, and Al3+. However, the use of NH4+ was restricted due to ammonia-nitrogen pollution, regarding in-situ leaching agents still remain controversial. It is imperative to comprehensively and systematically investigate the desorption mechanism of rare earth elements (REEs) from a microscopic perspective, especially when using Mg2+ and Al3+ as leaching agents. In this manuscript, the desorption behavior and mechanism of Y3+ from ADY (IREO as adsorbents loaded with Y3+) were studied, along with a comparison of the Y3+ desorption capabilities of Mg2+ and Al3+ as leaching agents. The results showed that Y3+ could be effectively desorbed from IREO by both Mg2+ and Al3+, with Y3+ desorption yields of 93.1 % (pH 3.2, 0.06 mol/L) for Al3+ and 88.6 % (pH 6.0, 0.3 mol/L) for Mg2+, respectively. The superior Y3+ desorption capability of Al3+ arises from its higher valence, greater electronegativity, and smaller ionic radius compared to Mg2+. The higher valence imparts Al3+ greater charge density, while the greater electronegativity enables Al3+ to more readily substitute for Y3+. Additionally, the smaller ionic radius facilitates the entry of Al3+ into clay minerals interlayers. At high H+ concentrations, the Y3+ desorption capabilities of Mg2+ and Al3+ were both higher than at the original pH without acid addition, primarily due to the influence of H+, which could leach Y3+ from the un-exchangeable phase, but also significantly increased the leaching of impurities. The isotherms and kinetics demonstrated the desorption of Y3+ in the case of Mg2+ and Al3+ existing followed the Langmuir and pseudo-second-order models, indicating homogeneous, chemisorption-governed processes. Furthermore, ATR-FTIR, XPS, and DFT results revealed Y3+ desorption occurred by breaking SiOY bonds and ion exchange with Mg2+/Al3+ to form SiOMg/Al bonds.

Strengthening rare earth and inhibiting aluminum leaching in magnesium salt-acetic acid compound system from ion-adsorption type rare earth ore

The leaching process of rare earth (RE) from ion-adsorption type rare earth ore (IATREO) using ammonium salt or magnesium salt as leaching agents presents challenges to inefficient leaching of RE elements and simultaneous leaching of ion-exchangeable phase aluminum (Al). This paper introduced acetic acid (HAc) into the leaching process of IATREO, to enhance the leaching of RE elements and inhibit the leaching of ion-exchangeable phase Al. The results show that RE elements and HAc mainly existed in the form of REAc2+, with a relative proportion of approximately 15 %. The presence of the HAc-Ac- conjugate acid-base pair provided a buffer capacity. In the MgSO4-HAc compound system, column leaching was controlled by internal diffusion, and the supplementation of HAc decreased the activation energy of the RE leaching reaction to 7.11 kJ/mol while increasing the leaching rate. Besides, the HAc-Ac- buffer system increased the pH of the leaching process and promoted the hydrolysis of ion-exchangeable phase Al, thereby inhibiting its leaching. Single-factor experiments indicated that under the optimal conditions, the leaching efficiency of RE elements reached 98.40 %, while the leaching efficiency of Al was 66.61 %. Compared with the ammonium and magnesium salts leaching systems, the leaching efficiency of RE elements increased by more than 6 %, while the leaching efficiency of Al was reduced by 23.33 %. This paper plays an important role in promoting the efficient and green extraction of IATREO.

Efficient enrichment and selective recovery of rare earths from sulfate leachate of ion-adsorption type rare earth ore by extraction with HPOAc

The efficient enrichment and separation of rare earth elements (REEs) from sulfate leachates of ion-adsorption type rare earth ore (IATREO) is still a challenge. This work presents a novel extractant 2-(bis((2-ethylhexyl)oxy)phosphoryl)-2-hydroxyacetic acid (HPOAc) for the selective extraction and efficient enrichment of REEs from sulfate leachates of IATREO. HPOAc exhibits higher extraction ability for all fifteen REEs(III) than naphthenic acid (NA) at pHini = 1.56. Furthermore, it has no drawbacks of di-(2-ethylhexyl) phosphoric acid (P204) and 2-ethylhexyl phosphoric acid mono-2-ethylhexylester (P507) such as weak extraction ability towards light REEs(III) and high stripping acidity for heavy REEs(III). It has better separation performance for metal ion impurities than P204 and P507, especially for the typical impurity Al(III). Furthermore, the HPOAc system has better phase separation behavior and extraction phenomena. A simulated operation with two-stage counter-current extraction and single-stage stripping of REEs was carried out using unsaponified HPOAc. The recovery of REEs reaches 98.7 %. The concentration of REEs increases from 0.44 to 130.35 g/L, indicating a nearly 300-fold increase. Furthermore, the content of REEs increases from 77.8 wt% to 97.6 wt%. So HPOAc has the potential to selectively recover REEs from sulfate leachates of IATREO.

Effective extraction of rare earth elements from ion-adsorption type rare earth ore by three bioleaching methods

Rare earth elements (REEs) are essential elements in many technology industries. The commonly used ammonium salt method has caused a bad impact on environment. Bioleaching is widely recognized as a low energy, relatively simple and environmentally friendly method. The purpose of this work is to extract REEs from ion-adsorption type rare earth ore by using three different bioleaching methods (one-step, two-step, and spent medium method, respectively) and the strain used was Aspergillus niger strain. Major organic acids produced during microbial growth were detected and the REEs leaching efficiency of three methods was compared. In addition, the interaction between the strain and their metabolites and rare earth ore was investigated by FT-IR, XRD, SEM-EDS, and TEM-EDS during the leaching process. In the end, it was found that the spent medium method had the best leaching effect, and various characterization methods showed that the three bioleaching methods had obvious changes before and after leaching, among which the spent medium method had the most significant effect. Additionally, through the analysis, it can be concluded that the complexation and acidolysis may occur in the bioleaching process.

Accumulation, translocation, and fractionation of rare earth elements (REEs) in fern species of hyperaccumulators and non-hyperaccumulators growing in urban areas

The issue of ion-adsorption type rare earth deposits (IADs) in urban areas of South China has garnered significant attention due to its environmental implications. Hyperaccumulator-based phytoremediation is a potentially effective solution for reducing the environmental impact of IADs in urban areas, particularly using ferns as they are known to be REE hyperaccumulators. However, the ability of different fern species to accumulate REEs in urban areas remains unknown. In this study, four fern species, including known hyperaccumulators (Dicranopteris linearis and Blechnum orientale) and other ferns (Pteris ensiformis and Cibotium barometz), were studied to investigate their REE accumulation abilities in the Guangzhou urban area. The aboveground parts of Dicranopteris linearis (848.7 μg g−1) and Blechum orientale (1046.8 μg g−1) have been found to accumulate high concentrations of REEs, demonstrating they probably can be applied for phytoremediation in the natural environments. Despite having lower REE concentrations than REE hyperaccumulators, Pteris ensiformis and Cibotium barometz still probably have the function as phytostabilizers in urban areas, as REEs can be enriched in their roots beyond the normal levels of plants. The enrichment of REEs in ferns is influenced by the availability of various nutrients (K, Ca, Fe, and P), which probably can be associated with different growth processes. The four fern species show LREE enrichment, moderate Eu anomalies and different Ce anomalies. It is difficult to absorb and transfer Ce to the aboveground parts of Blechnum orientale and Cibotium barometz. The study also identified selective enrichment of Ce in Pteris ensiformis, which has potential for comprehensive extraction of REEs when combined with other REE hyperaccumulators. REE fractionations are probably determined by the specific characteristics of different fern parts. Overall, these findings provide insights for addressing potential environmental problems related to IADs and offer guidelines for phytoremediation technology in addressing high REE levels in urban areas.

Utilization of Aspergillus niger strain to leach rare earth elements based on untargeted metabolomics analysis

With the continuous improvement in technology, the potential of rare earth elements (REEs) is constantly being tapped. Some of these REEs are valuable additives in the high-tech field. Bioleaching is an effective and clean method for extracting REEs from ion-adsorption type rare earth ore. In this study, the effect of non-contact bioleaching of REEs by Aspergillus niger strain was investigated, and the optimal culture conditions of strain and the optimal leaching conditions of rare earth ore were investigated. In addition, untargeted metabolomics was used to explore the differential metabolites produced by the strain before and after leaching and to verify the metabolites affected during leaching. The results showed that the REEs leaching efficiency was indeed improved by changing the temperature, pH, shaking speed and liquid–solid ratio. Metabolomic experiments showed that organic acids and their derivatives played important roles, and most of them were down-regulated after leaching.

Spatial Heterogeneity of Rare Earth Elements: Implications for the Topsoil of Regional Ion-Adsorption Type Rare Earth Deposit Areas in Southern China

The migration and spatial distribution characteristics of topsoil rare earth elements (REEs) are significant for the risk assessment of the external environment. However, the spatial distribution of REEs in the topsoil of ion-adsorption type rare earth element (REE) mining areas is poorly studied. We aimed to determine the differences and control factors of the spatial distribution of REEs in the topsoil of typical rare earth mines in South Jiangxi, South China. Sixty-five topsoil samples and eighteen profile samples were collected and analyzed for their rare earth content to elucidate spatial autocorrelation and heterogeneity using statistical analysis software (IBM SPSS Statistics 26.0.0.0, GS+9.0, and Arcgis10.2.0.3348). Moran index analysis showed that the positive correlation between sampling points was significant within the range of 0–500 m. The best fitting models of the semi-variance variogram were the exponential model, Gaussian model, and spherical model. The sequence of the spatial structure (C0 + C) was Ho > Tb > La > Pr > Nd > Sm > Gd > Tm > Lu > Dy > Er > Yb > Ce > Eu. The spatial fractal distribution pattern was Ho > Tb > Lu > Er > Dy > Yb > Tm > Gd > Ce > La > Eu > Sm > Pr > Nd. This indicated that the light rare earth elements (LREEs) and heavy rare earth elements (HREEs) in the topsoil were significantly different from the other sediments. This study provides new evidence for the environmental quality assessment of the in situ leaching of ionic rare earth ores into the topsoil layer.

Research on quantitative inversion of ion adsorption type rare earth ore based on convolutional neural network

Rare earth resource is a national strategic resource, which plays an essential role in the field of high technology research and development. In this paper, we aim to use remote sensing quantitative inversion prospecting technology, use surface-to-surface mode, and model inversion and evaluation through convolutional neural network model to achieve a new research method for large-scale, low-cost, rapid and efficient exploration of ion-adsorbed rare earth ore. The results show that the RE2O3 content of samples has significant negative correlation with the second, third and fourth band of GF-2 image, but has no significant correlation with the first band of GF-2 image; the convolution neural network model can be used to reconstruct the RE2O3 content. The content distribution map of RE2O3 obtained by inversion is similar to that of geochemical map, which indicates that the convolution neural network model can be used to invert the RE2O3 content in the sampling area. The quantitative inversion results show that the content distribution characteristics of ion adsorption rare earth ore in the study area are basically consistent with the actual situation; there are two main high anomaly areas in the study area. The high anomaly area I is a known mining area, and the high anomaly area II can be a prospective area of ion adsorption type rare earth deposit. It shows that the remote sensing quantitative inversion prospecting method of ion adsorption type rare earth deposit based on Convolutional Neural Networks (CNN) model is feasible.

Comparative chemical and non-contact bioleaching of ion-adsorption type rare earth ore using ammonium sulfate and metabolites of Aspergillus niger and Yarrowia lipolytica to rationalise the role of organic acids for sustainable processing

Ion-adsorption type rare earth ore mainly contains medium and heavy REEs, which are regarded as strategic mineral resources. At present, leaching REEs with chemical reagents has been restricted, while bioleaching is better for environmental protection. It is also found that if strains directly act on ore for in situ leaching, the harsh conditions will adversely affect the growth of strains. Non-contact bioleaching can effectively solve this problem, however, it is rarely reported and compared with chemical leaching. In this study, taking Aspergillus niger and Yarrowia lipolytica as research objects, the feasibility of using the metabolites produced by two strains to leach REEs is determined, and the mechanism is investigated and compared with that of ammonium sulfate. In addition, this study is the first to leach REEs by the Yarrowia lipolytica strain under neutral conditions, while the Aspergillus niger strain is more adaptable to acidic environment. The experimental results showed that Aspergillus niger (glucose as the carbon source) reached the highest leaching efficiency of 91%, Aspergillus niger (sucrose as the carbon source) reached 66%, and Yarrowia lipolytica reached only 34%. Furthermore, both strains could produce different concentrations of organic acids that are effective for REE leaching. The obtained results are relevant for the future development of ion-adsorption type rare earth ore.

Ion-adsorption type rare earth tailings for preparation of alkali-based geopolymer with capacity for heavy metals immobilization

Ion-adsorption type rare earth tailings (RET), a type of solid waste that contains clay minerals, were used as a starting material to prepare alkali-based geopolymer. The effects on the compressive strength of RET-based geopolymer, including the modulus and concentration of the alkaline activator, curing temperature, and liquid/solid ratio, were investigated. Pb2+ and Cd2+ were added during the preparation of the RET-based geopolymer for evaluating the immobilization capacity of heavy metals in the as-obtained geopolymer. The results showed that geopolymer with a compact and dense microstructure was obtained through the optimization of the above factors, with the highest compressive strength being 28.5 MPa. The leaching test indicated that the RET-based geopolymer possessed a desirable capacity for immobilizing heavy metals, where the immobilization efficiency of Pb2+ was above 99% and that of Cd2+ ranged from 92% to 96%. Heavy metals were immobilized in the RET-based geopolymer matrix through the formation of chemical bonds (T (Si, Al)–O–M (Pb, Cd)) or through an electrostatic attraction between the metal cations and negatively charged [AlO4]−.

Insight into leaching of rare earth and aluminum from ion adsorption type rare earth ore: Adsorption and desorption

Clay minerals are inferred to be the primary host materials for ion-exchangeable rare earth in ion adsorption type rare earth ore (IAREO). During the rare earth leaching process, the adsorption and desorption reactions of the cations controlling the leaching process continue to occur at the clay minerals-leaching agent solution interface. In order to understand the leaching mechanism and behavior of rare earth and co-leached aluminum, adsorption, competitive adsorption, and desorption experiments were carried out using kaolin as a typical clay mineral. The powerful electrostatic attraction and concentration driving forces facilitate the adsorption of cations. The adsorption ability and competitive adsorption ability of cations depend on their charge, hydration radius, and hydrolysis properties, and decrease in the order of La3+, Y3+, Al3+, Mg2+, and NH4+. The desorption of rare earth and aluminum is positively affected by the concentration-driving force exerted by high concentrations of Mg2+ and NH4+, with the order of the desorption ability being opposite to the adsorption ability. However, unspecified interactions between clay mineral particles enhanced by high-concentration desorbents, especially by Mg2+ than NH4+, will adversely affect desorption reactions, which result in lower desorption efficiencies of rare earth and aluminum obtained with magnesium sulfate compared to those obtained with ammonium sulfate at high concentrations. Solid-phase Al(OH)3 generated at a high peak aluminum concentration leads to a considerably delayed aluminum efflux, thereby partially separating the rare earth from aluminum during the actual column leaching process. To advance the mining technology of IAREO by selectively improving the rare earth leaching efficiency with minimal leaching agent consumption, higher charged cations with concentrations limited to suitable levels should be preferred as leaching agents.

Soil Environmental Quality Assessment around the Undeveloped Ion Adsorption Type Rare Earth Ore in Southern Jiangxi

Soil Environmental Quality Assessment around the Undeveloped Ion Adsorption Type Rare Earth Ore in Southern Jiangxi

Nitrogen removal performance and microbial community analysis of immobilized biological fillers in rare earth mine wastewater

The present study sought to treat the ion-adsorption type rare earth mine wastewater in a pilot plant system using the nitritation-denitrification process with immobilized biological fillers. Meanwhile, the microbial community structure in the immobilized fillers was analyzed. The ammonia nitrogen removal rate of the nitritation fillers reached 0.43 kg N m−3 d−1 on day 61 (28.1 °C) and the total nitrogen removal rate of the denitrification fillers reached 0.51 kg N m−3 d−1 on day 58 (27.8 °C) under the hydraulic retention time of 3.4 hr and a fillers volume ratio of 8% (v/v). The average NH4+-N and TN removal efficiencies of the nitritation-denitrification process were 96.9% and 96.8%, respectively, during the steady state operation period (day 26–72). The results also indicate that high DO (5.5–6.5 mg L−1) could induce rapid growth of nitrite-oxidizing bacteria (NOB) in the nitritation fillers, even though the initial NOB proportion is extremely low. The optimal operational performance of the denitrification fillers reactor was the COD/(NO2−-N + NO3−-N) ratio of 3.7–4.2. The high-throughput sequencing analysis showed that the functional bacteria in the immobilized fillers could maintain a competitive advantage. The abundance of Nitrosomonas in the nitritation fillers increased from 6.58% to 21.24%, while Thauera and Ottowia were the dominant denitrifying bacteria genera in the denitrification fillers.

Coordination–reduction leaching process of ion-adsorption type rare earth ore with ascorbic acid

The magnesium sulfate (MgSO4)–ascorbic acid (Vc) compound leaching technique can extract rare earth elements (REEs) existing in ion-exchangeable phase and colloidal phase from ion-adsorption type rare earth ore through the synergy effect of coordination and reduction, but its reaction process and mechanism remain unclear. In this paper, the coordination–reduction leaching mechanism was analyzed from the perspectives of leaching thermodynamics and kinetics, which provide theoretical guidance for the compound leaching process. In the case of neodymium, about 45% of dissolved neodymium will exist as the complex species of NdVc3(aq) in Nd–Vc–sulfate system. Based on this, it is deduced that the Gibbs free energy of the leaching reaction of ion-exchangeable phase REEs will change to a more negative value through the coordination of REEs cations and Vc anions in the MgSO4 leaching process. In addition, the Eh–pH diagrams of Ce–SO42––H2O and Fe–SO42––H2O together with the dissolution experiments confirm that the added Vc initiates the leaching process of colloidal phase REEs through reduction–dissolution reaction. Through the study of leaching kinetics, the leaching of REEs is controlled by diffusion and chemical reaction in the compound leaching system since colloidal phase REEs are leached. Therefore, the addition of Vc can shift the leaching equilibrium to a more favorable state and accelerate leaching process. The rare earth leaching efficiency of ion–exchangeable phase and colloidal phase can be effectively improved by increasing the reaction temperature, the concentrations of leaching agent and Vc, and the leaching agent acidity.

Adsorption mechanism of yttrium ions onto ion-adsorption type rare earths ore

Ion-adsorption type rare earths ore, as the primary source for middle-heavy rare earth elements, was extracted by various electrolytes via the adsorption–desorption effect. In this work, adsorption behavior and mechanism for yttrium ions onto ion-adsorption type rare earths ore as adsorbents were investigated systematically and comprehensively. The isotherms and kinetics suggested the adsorption of yttrium ions was consistent to Langmuir and pseudo-second-order model, revealing that the adsorption process was homogeneous and primarily governed by chemical adsorption. Maximum adsorption capacity could attain as 4.45 mg·g−1 in pH of 3 with 10 g·L−1 yttrium ions. Moreover, thermodynamics analysis indicated the adsorption process was spontaneous, and random. ATR-FTIR, XPS and DFT results indicated that Y(III) adsorbed onto ion-adsorption type rare earths ore surface possibly via Si-O-Y bond.

Mineralization of ion-adsorption type rare earth deposits in Western Yunnan, China

With the widespread application of heavy rare earth elements (HREEs) in high-tech fields, ion-adsorption type rare earth element (iREE) deposits have attracted much attention as the main output deposit type of HREE metals. In recent years in western Yunnan, southwest China, iREE deposits have made some large discoveries and received a high degree of attention. In this article, we summarize the metallogenic background, distribution, and metallogenic characteristics of iREE deposits in the Tengchong and the Lincang Granite Belt in western Yunnan, and analyzes the roles of ore-forming parent rock, regional metamorphism and alteration, epigenesis, and granite regolith composition in the metallogenesis of the iREE deposit in western Yunnan. It is believed that the high REE content granite parent rocks, metamorphic or magmatic-hydrothermal alteration, hot and humid climate, gentle topography, large and thick granite regolith are all favorable factors for iREE deposit formation. The long-term and multi-stage magmatic evolution formed high REE content granite parent rocks. Strong magmatic-hydrothermal activity and strong metamorphism associated with regional slip movement have contributed to the enrichment of REE elements and the formation of easily dissociated REE-bearing minerals, laying the material foundation for iREE deposits. The humid, hot and rainy climate and the vegetation-rich surface environment are conducive to weathering, which contributes to the formation of granite regolith and clay minerals, and the dissociation of REE-bearing minerals. Favorable topographical areas help to retain large-scale and thicker granite regolith, in which the clay minerals continue to adsorb the REE ions which have been infiltrated and migrated by the aqueous solution downward, leading to the gradual enrichment of REE elements and the formation of iREE deposits.

New insight into biotite weathering in the subtropic Tongcheng granite regolith, Hubei Province, South China

Alteration of biotite during igneous rock weathering plays an important role in global geochemical cycle and formation of ion-adsorption type rare earth element ores. In order to better understanding the transformation and geochemical processes of biotite weathering, investigation of alteration of biotite was undertaken in the granite regolith in subtropical Tongcheng, Hubei Province, South China. Our results show that weathering of biotite synchronously produced randomly interstratified biotite/vermiculite (B/V) and halloysite, and the B/V clay partially decomposed into discrete vermiculite in the topsoil due to increasing weathering. Vermiculitization of biotite involved leaching of K+ and accumulation of hydrated Mg2+ and Fe3+ in the interlayer space of biotite precursor and thus occurred in a solid-solid state transformation. The vermiculite components in B/V phase are hydroxyl-interlayered species, and the neoformed halloysite could not be expanded by formamide treatment, indicative of dehydrated halloysite. Halloysite occurs in tubular morphology at the edge of biotite or in well-oriented lath-like clusters on the basal surface of biotite crystals. The former crystallized from solutions, whereas the latter formed from local leaching of SiO sheets of biotite and subsequently in situ recrystallization. The parallel lath-like halloysite clusters occur in certain extending directions with angles of ~30° and ~ 60° respectively, resulting from the size misfit between the tetrahedron and octahedron of the crystal structure of biotite precursor. Thus, the formation of halloysite can be considered as a dissolution–precipitation process.

Removal of aluminum from chloride leach solutions of rare earths using 3-((bis(2-ethylhexyloxy))phosphoryl)-3-phenylpropanoic acid (PPPA)

The extraction and separation of Al3+ from a chloride solution of rare earths was studied using 3-((bis(2-ethylhexyloxy))phosphoryl)-3-phenylpropanoic acid (PPPA) as the extractant. The effects of factors such as initial pH value (pHini), temperature and saponification degree were investigated. The extraction is a cation exchange process deduced by the slope analysis method. Increasing the temperature facilitates the separation of aluminum from rare earths. Stripping of the loaded Al3+ can be achieved by mineral acid solutions of concentrations of 1.0 mol/L or higher. A cascade extraction process was used to remove Al3+ from a chloride liquor of the concentrate of ion-adsorption type rare earth ore. The Al3+ concentration in the aqueous solution decreased from 304.5 mg/L to 4.35 mg/L, and the recovery of rare earths was 95.6% after 5 stages of extraction and 2 stages of scrubbing.