Journal of Rare Earths最新文献

Surface-modified neodymium selenide nanoparticles for 5-fluorouracil delivery 用于5-氟尿嘧啶递送的表面改性硒化钕纳米颗粒

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-04-23 DOI: 10.1016/j.jre.2025.04.010

Ujma Ashapak Tamboli , Charan Singh Pawar , Varnitha Manikantan , Anthonysamy Kulandaisamy Preetha Immaculate , Sudhaker Raboni Grace , Mano Magdalin Rubella Kennedy , N. Rajendra Prasad , Israel V.M.V. Enoch

Neodymium selenide nanoparticles were synthesized and surface-modified using β-cyclodextrin-citrate to control agglomeration and achieve the desired particle size. The nanoparticles were characterized by various techniques, including X-ray diffraction, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). XRD results reveal high crystallinity, with characteristic peaks corresponding to Nd₂Se₃, while TEM analysis shows rod-shaped nanoparticles with an average size of ∼55 nm. The presence of neodymium and selenium in the +3 oxidation state was confirmed by XPS. Thermogravimetric analysis indicates that the β-cyclodextrin-citrate coating accounts for approximately 30% of the nanoparticle mass and remains stable up to 800 °C. The optical properties of the nanoparticles were studied using UV–Vis–NIR spectroscopy, revealing broad absorption in the UV and NIR regions. Magnetic characterization shows soft ferromagnetic behavior, with a saturation magnetization value of 0.20 emu/g. The nanoparticles were used for controlled release of 5-fluorouracil, exhibiting a pH-sensitive release profile. Studies on MCF-7 cells demonstrate that 5-fluorouracil-loaded nanoparticles enhance cytotoxicity, reactive oxygen species generation, and apoptosis compared to bare nanoparticles. The IC₅₀ value of (13.78 ± 1.24) μg/mL indicates a significantly high cytotoxic activity of the drug-loaded nanoparticles against breast cancer cell lines. These findings suggest that the nanoparticles are a promising drug delivery system for enhanced cancer treatment, combining the controlled drug release with targeted cellular effects.

合成了硒化钕纳米颗粒，并用β-环糊精-柠檬酸盐对其进行表面修饰，以控制团聚，达到理想的粒径。通过x射线衍射、透射电子显微镜（TEM）和x射线光电子能谱（XPS）等多种技术对纳米颗粒进行了表征。XRD结果显示其结晶度高，特征峰对应于Nd2Se3，而TEM分析显示其平均尺寸为~ 55 nm的棒状纳米颗粒。XPS证实了钕和硒在+3氧化态的存在。热重分析表明，β-环糊精-柠檬酸盐涂层约占纳米颗粒质量的30%，并且在800℃下保持稳定。利用紫外-可见-近红外光谱研究了纳米颗粒的光学性质，发现其在紫外和近红外区域具有广泛的吸收。磁性表征为软铁磁行为，饱和磁化值为0.20 emu/g。该纳米颗粒用于5-氟尿嘧啶的控释，表现出ph敏感的释放谱。对MCF-7细胞的研究表明，与裸纳米颗粒相比，负载5-氟尿嘧啶的纳米颗粒增强了细胞毒性、活性氧的产生和细胞凋亡。IC50值为（13.78±1.24）μg/mL，表明载药纳米颗粒对乳腺癌细胞株具有较高的细胞毒活性。这些发现表明，纳米颗粒结合了药物释放控制和靶向细胞效应，是一种很有前景的药物传递系统，可用于增强癌症治疗。

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引用次数: 0

Near-infrared emission of Eu2+ in M4Li(BN2)3 (M = Ca, Sr, Ba) M4Li(BN2)3 （M = Ca, Sr, Ba）中Eu2+的近红外发射

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-03-06 DOI: 10.1016/j.jre.2025.03.004

Dilare Halmurat , Xinyu Zhang , Litipu Aihaiti , Rong-Jun Xie

Eu²⁺-doped phosphors show broadband absorption, tunable emission and high quantum efficiency due to the parity-allowed 5d→4f transitions, allowing them to be used in solid-state lighting. To expand their applications in other fields such as detection and sensing technologies, the Eu²⁺ emission needs to be tuned into the near-infrared region, but it is a big challenge to obtain Eu²⁺ near-infrared region emitters due to the absence of host compounds with extremely large crystal-field splitting. In this work, we chose M₄Li(BN₂)₃ (M = Ca, Sr, Ba) as a host and realize the near-infrared region emission of Eu²⁺ in it. Among these phosphors, Ba₄Li(BN₂)₃:Eu²⁺ exhibits the longest emission of 880 nm and the largest full-width at half maximum of 276 nm under 450 nm excitation, while Ca₄Li(BN₂)₃:Eu²⁺ and Sr₄Li(BN₂)₃:Eu²⁺ emit at 740 and 680 nm, respectively. We observe an interesting phenomenon that the energy shift of emission is linearly related to the radius difference between the alkaline earth cation and the activator Eu²⁺ in this system.

Eu2+掺杂的荧光粉具有宽带吸收、可调谐发射和高量子效率，这是由于其允许奇偶性的5d→4f跃迁，使其能够用于固态照明。为了扩大其在检测和传感技术等其他领域的应用，需要将Eu2+发射调谐到近红外区域，但由于缺乏具有极大晶体场分裂的宿主化合物，因此获得Eu2+近红外区域发射体是一个很大的挑战。本文选择M4Li(BN2)3 （M = Ca, Sr, Ba）为主体，在其中实现了Eu2+的近红外发射。其中，Ba4Li(BN2)3:Eu2+在450 nm激发下的最长发射波长为880 nm，最大全宽为276 nm，而Ca4Li(BN2)3:Eu2+和Sr4Li(BN2)3:Eu2+的发射波长分别为740 nm和680 nm。我们观察到一个有趣的现象，在这个体系中，发射的能量位移与碱土阳离子和活化剂Eu2+之间的半径差成线性关系。

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引用次数: 0

Synthesis and application of a quaternary ammonium ionic liquid collector for flotation separation of fluorite and bastnaesite 萤石与氟碳石浮选分离用季铵离子液体捕收剂的合成与应用

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-03-17 DOI: 10.1016/j.jre.2025.03.013

Yanxu Wang , Siyuan Yang , Qianqian Wang , Bo Chen , Shenxu Bao , Wenbo Li , Cheng Liu

The efficient flotation separation of rare earth elements (REEs) from gangue minerals is crucial in mineral processing. This study synthesized a quaternary ammonium salt ionic liquid collector, tetrabutylammonium salicylhydroxamate (T-S), and investigated its performance in separating bastnaesite and fluorite. T-S was synthesized from salicylhydroxamic acid (SHA) and tetrabutylammonium chloride (TBAC), and its molecular structure was characterized using Fourier transform infrared (FTIR) spectroscopy. Microflotation tests indicate that T-S outperforms SHA and TBAC in both collecting ability and selectivity for bastnaesite. Adsorption, zeta potential, and infrared spectroscopy measurements reveal that T-S exhibits stronger adsorption on bastnaesite compared to SHA and TBAC. X-ray photoelectron spectroscopy (XPS) and molecular dynamics simulations (MDS) results confirm that chemical adsorption occurs between Ce on the bastnaesite surface and the –C(=O)NHOH groups of T-S. Moreover, the interaction between T-S and the bastnaesite surface is stronger than that with the fluorite surface. This work provides valuable insights for designing ionic liquid collectors for the flotation separation of bastnaesite and fluorite.

脉石矿物中稀土元素的高效浮选分离是选矿的关键。合成了季铵盐离子液体捕收剂水杨基羟酸四丁基铵（T-S），并考察了其分离氟碳铈矿和萤石的性能。以水杨基羟肟酸（SHA）和四丁基氯化铵（TBAC）为原料合成了T-S，并用傅里叶变换红外光谱（FTIR）对其分子结构进行了表征。微浮选试验表明，T-S对氟碳醚的富集能力和选择性均优于SHA和TBAC。吸附、zeta电位和红外光谱测量表明，与SHA和TBAC相比，T-S在氟碳醚上的吸附更强。x射线光电子能谱（XPS）和分子动力学模拟（MDS）结果证实了氟碳铈表面的Ce与T-S的-C (=O)NHOH基团之间发生了化学吸附。此外，T-S与氟碳石表面的相互作用强于与萤石表面的相互作用。本研究为氟碳石和萤石浮选分离离子液体捕收剂的设计提供了有价值的见解。

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引用次数: 0

Enhanced phosphate removal in water by magnesium-modified biochar/yttrium alginate hybrid biogel polymer 镁改性生物炭/海藻酸钇杂化生物凝胶聚合物增强水中磷酸盐的去除

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-04-28 DOI: 10.1016/j.jre.2025.04.018

Qian'ge Zhao , Beigang Li , Xueying Zhou

A novel macroparticle magnesium-modified biochar/yttrium alginate (Mg-BC/SA-Y) hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer, and its properties were characterized. The obtained Mg-BC/SA-Y biogel beads have a particle size of approximately 1.5 mm, featuring abundant network pores and an uneven, distinctive surface. The performance and mechanisms of Mg-BC/SA-Y for phosphate adsorption were thoroughly investigated. The findings indicate that Mg-BC/SA-Y removes up to 95.7% of phosphate at pH 4.0 and 298 K, and also achieves a phosphate removal efficiency of over 80% within a pH range of 3.0–11.0. The adsorption capacity of Mg-BC/SA-Y for phosphate is nearly four times that of BC. The spontaneous adsorption processes and endothermic adsorption behavior can be elucidated by the pseudo-second-order rate and Langmuir equations, respectively. Phosphate adsorption is almost unaffected by water ionic strength and common coexisting ions, except for the influence of high-concentration F^– ions. The recyclable biogel beads can be reused after adsorbing phosphate, and represent excellent stability and practicability in real water. The mechanisms of ligand exchange, inner-sphere complexation and electrostatic attraction are involved in phosphate removal. Mg-BC/SA-Y biogel polymer is a desirable and sustainable biosorbent for treating water with excessive phosphate levels and reducing pollution and carbon emissions.

通过镁改性BC和海藻酸钇聚合物的快速溶液反应，制备了一种新型的宏观镁改性生物炭/海藻酸钇（Mg-BC/SA-Y）杂化生物凝胶复合材料，并对其性能进行了表征。所得Mg-BC/SA-Y生物凝胶珠的粒径约为1.5 mm，具有丰富的网状孔和凹凸不平的独特表面。研究了Mg-BC/SA-Y吸附磷酸盐的性能和机理。结果表明，Mg-BC/SA-Y在pH 4.0和298 K条件下，对磷酸盐的去除率高达95.7%，在pH 3.0 ~ 11.0范围内，对磷酸盐的去除率也达到80%以上。Mg-BC/SA-Y对磷酸盐的吸附量是BC的近4倍。自发吸附过程和吸热吸附行为可以分别用拟二阶速率方程和Langmuir方程来解释。除高浓度F离子影响外，磷酸盐吸附几乎不受水离子强度和常见共存离子的影响。可回收生物凝胶珠吸附磷酸盐后可重复使用，在实际水中表现出优异的稳定性和实用性。配体交换、球内络合和静电吸引等机制参与了磷酸盐的去除。Mg-BC/SA-Y生物凝胶聚合物是一种理想的可持续生物吸附剂，用于处理含有过量磷酸盐的水，减少污染和碳排放。

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引用次数: 0

Achieving high entropy in rare earth oxides: A detailed experimental procedure 在稀土氧化物中实现高熵：一个详细的实验程序

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-01-16 DOI: 10.1016/j.jre.2025.01.011

Ye Cheng , Ehsan Ghasali , Saleem Raza , Asif Hayat , Ming Liu , Junsheng Ye , Pengfei Zhang , Andrii Babenko , Jie Li , Yasin Orooji

This study explored the impact of sintering time and temperature on the synthesis and formation of high-entropy rare earth oxides (HEOs). By systematically varying the sintering conditions, a series of Lu₂Yb₂Tm₂Er₂O₁₂ samples was synthesized and their structural and chemical properties were analyzed using scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) elemental mapping, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS). According to XRD patterns, a single-phase cubic C-type structure is easier to form at higher sintering temperatures (1400–1500 °C), with sharper peaks signifying better crystallinity. With longer sintering times improving grain development and homogeneity, SEM research reveals a change in morphology from spherical grains at lower temperatures (1100–1200 °C) to blocky grains at higher temperatures (1300–1500 °C). HRTEM pictures verified the nanoparticles' strong crystallinity, and at higher temperatures, the lattice fringes widen and become more distinct, indicating better atomic ordering and diffusion. Stable and uniform high-entropy oxide production is indicated by the XPS spectra, which shows uniform elemental distribution and consistent chemical states of the constituent elements with very slight variations in the oxygen peaks. The findings highlight how important the sintering temperature is for reaching the intended high-entropy phase, with higher temperatures promoting improved atomic diffusion and compositional homogeneity. The results open the door for the use of high-entropy rare earth oxides in sophisticated functional materials by offering insightful information on how to best synthesize them.

本研究探讨了烧结时间和温度对高熵稀土氧化物（HEOs）合成和形成的影响。通过系统地改变烧结条件，合成了一系列Lu2Yb2Tm2Er2O12样品，并利用扫描电子显微镜（SEM）、能量色散x射线能谱（EDS）元素图、x射线衍射（XRD）、高分辨率透射电子显微镜（HRTEM）和x射线光电子能谱（XPS）对其结构和化学性质进行了分析。XRD分析表明，在较高的烧结温度（1400 ~ 1500℃）下更容易形成单相立方C型结构，其峰更尖锐，表明结晶度更好。随着烧结时间的延长，晶粒的发育和均匀性得到改善，SEM研究表明，在较低温度下（1100-1200℃），晶粒的形貌从球形到块状，在较高温度下（1300-1500℃）。HRTEM图像证实了纳米颗粒的强结晶性，并且在较高的温度下，晶格条纹变宽并变得更加明显，表明原子有序和扩散更好。XPS光谱表明，高熵氧化物的生成稳定均匀，元素分布均匀，组成元素的化学状态一致，氧峰变化很小。研究结果强调了烧结温度对于达到预期的高熵相的重要性，较高的温度促进了原子扩散和成分均匀性的改善。该研究结果为高熵稀土氧化物在复杂功能材料中的应用打开了大门，为如何最好地合成它们提供了有见地的信息。

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引用次数: 0

Design of hydrogen-liquefied magnetic refrigeration materials by elemental regulation in RE3–xHoxB0.5C3.5 (RE=Dy, Tb) compounds re3 - xhoxb0.5 . 5c3.5 （RE=Dy, Tb）化合物元素调控设计氢液化磁致冷材料

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-02-26 DOI: 10.1016/j.jre.2025.02.021

Haobo Sun , Lu Tian , Jianjian Gong , Zhenxing Li , Zhaojun Mo , Guodong Liu , Jun Shen

The search for high-abundance compounds containing rare earth elements to develop high-performance magnetic refrigeration materials for hydrogen liquefaction has become a particularly attractive research direction. We successfully manipulated the magnetic interactions in tetragonal rare earth carbides (RE₃C₄) by doping them with boron (B) element, transforming their state from antiferromagnetic to ferromagnetic. Theoretical calculations and experimental results indicate that the transition in magnetic interactions may be due to the synergistic effects of electronic structure and lattice distortions. Building on this, further doping with holmium (Ho) element was used to adjust the magnetic transition temperature of the system. The results show that the magnetic transition temperature of this series of compounds can be effectively altered within the range of 26–42.8 K. By optimizing the composition of rare earth elements, a series of novel candidate materials exhibiting significant magnetocaloric effects within the temperature range required for hydrogen liquefaction is successfully developed.

寻找含稀土元素的高丰度化合物开发用于氢液化的高性能磁制冷材料已成为一个特别有吸引力的研究方向。我们成功地通过在稀土碳化物（RE3C4）中掺杂硼(B)元素，使其从反铁磁态转变为铁磁态，从而控制了稀土碳化物（RE3C4）的磁相互作用。理论计算和实验结果表明，磁相互作用的转变可能是由于电子结构和晶格畸变的协同效应。在此基础上，进一步掺杂钬（Ho）元素来调节体系的磁转变温度。结果表明，该系列化合物的磁转变温度在26 ~ 42.8 K范围内可以有效改变。通过优化稀土元素的组成，成功开发了一系列在氢液化所需温度范围内表现出显著磁热效应的新型候选材料。

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引用次数: 0

Tailoring interaction between rhodium and CeO2 by crystal facets selection to enhance ethanol synthesis via CO2 hydrogenation 通过晶体面选择剪裁铑和CeO2之间的相互作用，以增强通过CO2加氢合成乙醇

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-03-19 DOI: 10.1016/j.jre.2025.03.017

Fei Hong, Dongsen Mao, Tao Meng, Guisheng Wu, Haifang Mao, Jun Yu

The hydrogenation of carbon dioxide to produce high-value fuels such as ethanol is currently a research hotspot, but addressing the low selectivity for ethanol remains a challenge. Herein, morphology-controlled CeO₂ with different exposed crystal facets, including nanorods (220), nanocubes (200) and nanoplatelets (111), were prepared and impregnated with rhodium (Rh) to obtain Rh/CeO₂ catalysts, and then the catalytic performance of CO₂ hydrogenation was investigated. Rh/CeO₂-r (nanorods) exhibits high efficacy for CO₂ hydrogenation to ethanol, giving a high ethanol selectivity of 20.9% with a moderate CO₂ conversion of 11.2%, and the one-pass ethanol productivity reaches 69.2 mmol/(g_Rh·h). Characterization results reveal that tuning the exposed crystal facets of the CeO₂ can tailor the interaction between Rh and CeO₂, and adjust the chemical state of the Rh species. Due to the abundant oxygen vacancies occupied on the exposed (220) facets of CeO₂ nanorods, multi-level interactions arise between Rh and CeO₂-r, and produce more content of Rh⁺ species. This interface facilitates the transformation of carbonate species into HCOO∗ and CO∗ simultaneously, finally boosting the ethanol formation by the C−C coupling reaction.

二氧化碳加氢生产乙醇等高价值燃料是目前的研究热点，但解决乙醇的低选择性仍然是一个挑战。在此基础上，制备了纳米棒（220）、纳米立方（200）和纳米片状（111）等不同暴露晶面的形貌可控的CeO2，并浸渍铑（Rh）制备了Rh/CeO2催化剂，考察了其对CO2加氢的催化性能。Rh/CeO2-r（纳米棒）对CO2加氢制乙醇具有较高的效率，乙醇选择性为20.9%，CO2转化率为11.2%，一次乙醇产率达到69.2 mmol/（gRh·h）。表征结果表明，调整CeO2的暴露晶面可以调整Rh和CeO2之间的相互作用，并调整Rh的化学状态。由于在CeO2纳米棒的暴露面（220）上占据了丰富的氧空位，Rh和CeO2-r之间产生了多层次的相互作用，并产生了更多的Rh+物质。该界面有利于碳酸盐同时转化为HCOO *和CO *，最终通过C - C偶联反应促进乙醇的生成。

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引用次数: 0

Recovery of rare earth elements and critical metals from thermally activated coal refuse using ferric sulfate bio acid 硫酸铁生物酸法从热活化煤矸石中回收稀土元素和关键金属

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-04-09 DOI: 10.1016/j.jre.2025.04.001

Wei Liu , Rick Honaker , Xinbo Yang

Extracting rare earth elements (REEs) from coal refuse is challenging due to their low concentrations and poor leachability. Bioleaching has emerged as a sustainable technology to recover REEs from low-grade materials. In this study, a ferric sulfate bio acid (BA) with an acidity of ∼0.2 mol/L H⁺, generated through regulated pyrite bio-oxidation, was used to leach REEs and critical metals (CMs) from coal refuse (ground to <1 mm) after 20-min roasting at 600 °C. The influences of solid/liquid (S/L) ratio (100–300 g/L) and leaching temperature (25–95 °C) on the leaching performance were examined. The leaching mechanisms were investigated by conducting stepwise precipitation tests and spectroscopic characterization. Results show that raising the leaching temperature to ≥65 °C accelerated the REE leaching kinetics but causes the loss of light REEs (LREEs) after reaching peak values at 30–60 min. Stage precipitation tests reveal that the loss is due to the incorporation of REEs, especially for LREEs, by gypsum and schwertmannite. The peak total REE (TREE) recovery of the BA leaching reaches 24.9% after 30 min of leaching at 75 °C with a S/L ratio of 200 g/L. Implementing the three-stage counter-current leaching increases the overall TREE recovery to 31.8% by recovering the REEs incorporated in the Fe and Ca precipitates. Meanwhile, promising recovery values of Li (55.5%), Mn (74.6%), Ni (41.6%), and Co (35.3%) are also achieved. This method provides a sustainable approach to extract REEs and critical metals from coal waste materials with a high treatment capacity.

从煤矸石中提取稀土元素具有浓度低、可浸性差的特点。生物浸出已成为一种从低品位材料中回收稀土元素的可持续技术。在这项研究中，通过调节黄铁矿生物氧化产生的硫酸铁生物酸（BA）酸度为~ 0.2 mol/L H+，在600℃下焙烧20分钟后，从煤矸石（磨至1 mm）中浸出稀土和关键金属（CMs）。考察了料液比（S/L）（100 ~ 300 g/L）和浸出温度（25 ~ 95℃）对浸出性能的影响。通过逐步沉淀试验和光谱表征研究了浸出机理。结果表明：将浸出温度提高至≥65℃，加速了稀土元素的浸出动力学，但在30 ~ 60 min达到峰值后导致轻稀土元素的损失；阶段沉淀试验表明，这些损失是由于稀土元素，特别是低稀土元素被石膏和许氏锰石掺入所致。在75℃、S/L比为200 g/L的条件下，BA浸出30 min后，总REE （TREE）回收率达到24.9%。采用三段式逆流浸出，通过回收Fe和Ca沉淀中的稀土元素，使总TREE回收率提高到31.8%。同时，Li（55.5%）、Mn（74.6%）、Ni（41.6%）和Co（35.3%）的回收率也达到了较好的水平。该方法为从煤炭废料中提取稀土和关键金属提供了一种可持续的方法，具有较高的处理能力。

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引用次数: 0

Revealing low-temperature reaction mechanism of cobalt-doped CeO2 catalyst for catalytic removal of methyl mercaptan 揭示了钴掺杂CeO2催化剂催化脱除甲基硫醇的低温反应机理

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-02-15 DOI: 10.1016/j.jre.2025.02.004

Zijun Huang , Xiaohua Cao , Huaiyu Xu , Miao Lin , Dedong He , Dingkai Chen , Jichang Lu , Yongming Luo

Methyl mercaptan (CH₃SH) is notorious for global air pollution owing to its odorous characteristics and adverse health effects. Although CeO₂ is currently regarded as a promising catalyst for CH₃SH decomposition, the high conversion temperature followed by high energy consumption is still a bottleneck. Herein, the cobalt-doped CeO₂ catalyst was synthesized by a facile one-pot preparation strategy and successfully reduces the decomposition temperature from 450 to 250 °C. Further studies demonstrate that the excellent low-temperature catalytic activity of Co_0.6Ce_0.4O_2–σ is attributed to its abundant oxygen vacancies and reactive oxygen species. Oxygen vacancies promote the adsorption and dissociation of CH₃SH, while reactive oxygen species facilitate the decomposition of CH₃SH. Moreover, Co acts as a sacrificial agent for the adsorption of sulfur species in CH₃SH, while Ce is responsible for the adsorption and activation of CH₃SH as the active metal phase. Furthermore, the migration and transformation mechanism of CH₃SH on the surface of Co_0.6Ce_0.4O_2–σ was determined via in situ diffuse reflectance infrared Fourier transform spectra (in situ-DRIFTS). This work provides a new strategy to synthesize high-performance catalysts for decomposing sulfur-containing volatile organic compounds (VOCs) at low temperatures, which is beneficial to decreasing the energy consumption.

甲基硫醇（CH3SH）因其气味特性和对健康的不利影响而成为全球空气污染的罪魁祸首。虽然CeO2目前被认为是一种很有前途的CH3SH分解催化剂，但高转化温度和高能耗仍然是瓶颈。本文采用简单的一锅制备策略合成了掺杂钴的CeO2催化剂，并成功地将分解温度从450℃降低到250℃。进一步的研究表明，Co0.6Ce0.4O2 -σ具有优异的低温催化活性是由于其丰富的氧空位和活性氧。氧空位促进CH3SH的吸附和解离，活性氧促进CH3SH的分解。Co作为CH3SH中硫类吸附的牺牲剂，Ce作为活性金属相负责CH3SH的吸附和活化。利用原位漫反射红外傅立叶变换光谱（in situ- drifts）测定了CH3SH在Co0.6Ce0.4O2 -σ表面的迁移转化机理。本研究为合成低温高效分解含硫挥发性有机化合物（VOCs）催化剂提供了新思路，有利于降低能耗。

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引用次数: 0

Enhanced flotation separation of bastnaesite and monazite by suspension roasting: A study of flotation performance and mechanisms 悬浮焙烧强化氟碳铈矿与独居石的浮选分离：浮选性能及机理研究

IF 7.2 1区化学 Q1 CHEMISTRY, APPLIED

Journal of Rare Earths

Pub Date : 2026-03-01 Epub Date: 2025-04-28 DOI: 10.1016/j.jre.2025.04.016

Linghui Zhang , Wenbo Li , Shaokai Cheng , Xiaolong Zhang , Junyan Sun , Rui Qu , Maoyuan Wang

Bayan Obo rare earth mine is the largest light rare earth resource worldwide, primarily extracts rare earth elements (REEs) from mixed RE concentrates with bastnaesite and monazite. Nevertheless, the adoption of the concentrated sulfuric acid roasting metallurgical process has resulted in damage to the environment. Therefore, this paper adopted the method of selective mineral phase transformation (MPT) followed by enhanced micro-flotation. By determining the optimal MPT conditions, the flotation recovery of bastnaesite-roasted products by the collector (phthalic acid, PA) is improved, and the enhanced separation of bastnaesite with monazite is realized. The results show that with the increase of roasting temperature and time, the bastnaesite decomposition product is CeOF and monazite does not change significantly. Subsequent micro-flotation exhibits a gradual decline in the PA consumption of bastnaesite-roasted products, while the flotation recovery of monazite-roasted products remains poor. The artificial mixed ore experiments result in a CeOF foam product with a content of 94.14% and a recovery of 85.80%, and a monazite tank product with a content of 73.53% and a recovery of 87.87%. Compared with the pre-roasting ore, the surface and interior of bastnaesite-roasted products develop numerous cracks and porosities, and no obvious structural damage is observed in monazite-roasted particles. As the roasting temperature increases, the mineral particles undergo recrystallization or closure, reducing the specific surface area of bastnaesite-roasted products and enhancing hydrophobicity, leading to diminished PA consumption. Fourier transform infrared and other flotation-relation tests show that PA is chemisorbed on the surface of CeOF. The MPT conditions are optimized in this study, which provides a reference for further advancing the efficient separation of bastnaesite and monazite.

白云鄂博稀土矿是世界上最大的轻稀土资源，主要从含氟碳铈矿和独居石的混合稀土精矿中提取稀土元素。然而，采用浓硫酸焙烧冶金工艺对环境造成了破坏。因此，本文采用了选择性矿物相变(MPT) -强化微浮选的方法。通过确定最佳MPT条件，提高了捕收剂（邻苯二甲酸，PA）对氟碳铈矿焙烧产物的浮选回收率，实现了氟碳铈矿与独居石的强化分离。结果表明：随着焙烧温度和时间的增加，氟碳铈矿的分解产物为CeOF，独居石的分解产物变化不明显；后续微浮选氟碳石焙烧产物PA用量逐渐下降，而单氮石焙烧产物浮选回收率仍然较差。人工混合矿试验得到的CeOF泡沫产品含量为94.14%，回收率为85.80%，独居石罐产品含量为73.53%，回收率为87.87%。与预焙烧矿相比，氟碳铈矿焙烧产物的表面和内部出现了大量的裂纹和孔隙，而独居石焙烧颗粒未见明显的结构破坏。随着焙烧温度的升高，矿物颗粒发生再结晶或闭合，降低了氟碳铈矿焙烧产物的比表面积，增强了疏水性，从而减少了PA的消耗。傅里叶变换红外和其他浮选关系测试表明，PA在CeOF表面发生了化学吸附。本研究对MPT工艺条件进行了优化，为进一步推进氟碳铈矿与独居石的高效分离提供了参考。

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