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Theoretical probe into universal tetrad effect for complexation discrepancy between lanthanide elements and organophosphoric extractant diethyl phosphoric acid

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Journal of Rare Earths 2024年第6期42卷 1142-1148,I0006页

作者： Haifeng Zheng Yanling Li Xuyi Zhang Jinglu Han Songsong Li Guolong Wu Qingshi Liu Xiaojuan Liu Wuping Liao State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei230026China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang330031China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341000China

The deep understanding of 4f-correlated electron motion behavior is experimentally limited due to similar physicochemical properties of rare earth elements(REEs).While the solvent extraction behavior originating from the continuous occupation of 4f electrons along the lanthanide family provides a particular platform to probe the 4f electrons motion behavior and its correlations to their versatile ***,the complexation between REEs and the prototypical extractant of diethyl phosphoric acid(DEP)was substantially studied based on quantum mechanical *** results firstly show that the average bond lengths between Ln and six coordinated oxygen atoms are consistent with lanthanide contraction phenomenon,and gadolinium break effect is also obviously ***,the"tetrad effect"is figured out based on the subtle discrepancy of 4f electrons occupation,namely La-Nd,Sm-Eu,Gd-Dy and ***,the main composition is 4f5d6p for La-Nd,while the discrepancy is due to the increasing electrons in the 5d shell,while it is 4f5d for *** Gd-Dy,their 4f orbitals accept little electrons and the donating electrons flow into 6s5d subshells due to the half-filled stability and the enhancement of shielding *** electrons donate into 5d6p subshells due to multiply electrons occupation of 4f orbitals for *** detailed analyses obviously clarify the"tetrad effect"along the lanthanide family due to the different variation of 4f orbital *** is expected that these microscopic understandings provide important guidance for the separation of REEs and the design of new extractants.

关键词： Theoretical calculation Rare earths 4f electron tetrad effect Gadolinium break

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REE tetrad effect as a Powerful Indicator of Formation Conditions of Karst Bauxites: A Case Study of the Shahindezh Deposit, NW Iran

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 912-927页

作者： Ali ABEDINI Mansour REZAEI AZIZI Ali Asghar CALAGARI Department of Geology Faculty of SciencesUrmia University*** UrmiaIran Department of Earth Sciences Faculty of Natural SciencesUniversity of Tabriz*** TabrizIran

Study of the concentration of major,trace,and rare earth elements(REE)in the Shahindezh karst bauxite deposit,northwestern Iran clarifies the relationship of the tetrad effect with geochemical parameters in the bauxite *** existence of irregular curves in the chondrite-normalized REE patterns as well as non-CHARAC behavior of geochemically isovalent pairs(Y/Ho)are related to the tetrad *** meaningful positive correlation between the sizes of the calculated T3 tetrad effect and some geochemical factors such as Y/Ho,ΣREE,La/Y,(La/Yb)N,and(LREE/HREE)N as well as some major oxides-based parameters like Al2O3+LOI/SiO2+Fe2O3,Al2O3/Fe2O3,Al2O3+LOI,IOL,and SiO2+Fe2O3indicate that the studied bauxite horizon was likely deposited by different(acidic and/or alkalic)solutions at different *** lower part of the studied horizon with a thickness of^4.7 m displays alkali characteristics whereas the upper parts of the horizon with a thickness of^5.3 m are characterized by more acidic *** results are fully supported by the co-occurrence of convex-concave tetrad effect curves in the chondrite-normalized REE ***,the tetrad effect phenomenon used in this study has proved to be a good and reliable geochemical proxy to assess the conditions of the depositional environment in the Shahindezh bauxite ores.

关键词： Geochemistry REE tetrad effect Karst bauxite Shahindezh Iran

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The Lanthanide tetrad effect in Argillic Alteration: An Example from the Jizvan District, Northern Iran

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1468-1485页

作者： Ali ABEDINI Mansour REZAEI AZIZI Ali Asghar CALAGARI Department of Geology Faculty of Sciences Urmia University Department of Earth Sciences Faculty of Natural Sciences University of Tabriz

Intrusion of quartz-monzodioritic igneous bodies of Oligocene age into Eocene lithic crystal tufts and trachy-basalts resulted in the occurrence of a widespread argillic alteration zone in the Jizvan district （northern Iran）. Mineralogically, the argillie alteration zone includes minerals such as kaolinite, quartz, smectite, pyrophyllite, muscovite-illite, alunite, rutile, calcite, feldspar, chlorite, hematite and goethite. Therefore, the non-CHARAC behaviour for trace elements in the argillic samples is reflected in the non-chondritic Y/Ho and Zr/Hf ratios and the irregular REE patterns, which appear related to the tetrad effect phenomenon. The chondrite-normalized REE distribution patterns indicate both concave （W-shaped） and convex （M-shaped） tetrad effects in the argillic samples. Based on the field evidence and the results from geochemical studies, it can be concluded that the samples from the argillic alteration zone having high fourth tetrad effect values （〉0.30） were developed in the fault and breccia zones. The results indicate that factors such as preferential scavenging by Mn-oxides, crystallization of clay minerals, fluid-rock interaction, overprint of hypogene mineral assemblage by supergene ones, and the structural control, have all played an important role in the occurrence of tetrad effects in samples of the argillic zone in the Jizvan district.

关键词： REE geochemistry tetrad effect argillic alteration Jizvan Iran

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Petrology, REE Geochemistry and tetrad effect of Some Muscovite Granites at Wadi El Gemal Area, South Eastern Desert, Egypt

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Journal of Geoscience and Environment Protection 2022年第2期10卷 75-93页

作者： Ahmed S. Shalan Nuclear Materials Authority El-Maadi Cairo Egypt

The muscovite granites at the study area are being emplaced into biotite granites and ophiolitic mélange settings. They occur in four exposures namely;Umm Seleimat, Sikait, Umm El Kheran and Umm Addebaa exposure. The presence of garnet and muscovite flakes may reflect the peraluminous nature of the studied muscovite granites. Petrographically, the studied granites are mostly subsolvus and consist of plagioclase, K-feldspars, quartz, muscovite and biotite. Garnet, zircon, allanite and opaques are accessories. The textural features of these granites are expressed by bent plagioclase lamellae, distorted microcline twinning, deformed mica flakes and development of myrmekite and recrystallization of feldspars into fine-grained aggregates. Umm Seleimat and Sikait exposures are more differentiated due to the presence of high content of K-feldspar and LREEs. The REE budget decreased from Umm Seleimat-Sikait exposures to Umm El Kheran-Umm Addebaa exposures as (514.5 - 495.6) to (195.9 - 197.7), respectively. Umm Seleimat-Sikait exposures have lower HREE/LREE (0.12 - 0.67), relative to Umm El Kheran-Umm Addebaa exposures (0.99 - 2.06). The studied granites revealed that the chondrite normalized REE patterns are the normal M-type of tetrad effect, where TE1,3 tetrad effect is higher than 1 in all samples which implies that there was an interaction between melt and water-haloid-rich fluid when these granites are crystallized from magma. Spectrometric values of Umm Seleimat and Umm Addebaa indicate that U content is more than Th content. Applying the U mobilization equation proved that the studied granites have been originated from a late magmatic phase of magma very rich in radioelements, also the majority of measurements lie above the zero line indicating that the studied granites affected with hydrothermal solutions rich in uranium than thorium which indicates uranium addition.

关键词： Wadi El Gemal Umm El Kheran REE Geochemistry tetrad effect Egypt

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Fractionation of Rare Earth Elements in Plants Ⅰ. Fractionation Patterns and Their Forming Mechanisms in Different Organs of Triticum Aestivum

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Journal of Rare Earths 2005年第2期23卷 224-229页

作者：梁涛丁士明张朝生张自立阎军才李海涛 Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Geography and Environmental Change Institute National University of Ireland Galway Ireland Department of Soil and Agrichemistry Anhui Agricultural University Hefei 230036China

Fractionations of rare earth elements (REEs) and the forming mechanisms in plants were studied using Triticum aestivum as plant material with application of exogenous REEs and hydroponic culture. REEs were significantly fractionated in different parts of Triticum aestivum. M-type tetrad effect could be observed in both root and shoot of Triticum aestivum, which might result from the different abilities of REEs to form phosphate precipitation. Middle REEs (MREEs), light REEs (LREEs) and heavy REEs (HREEs) were enriched in root, stem and leaf of Triticum aestivum, respectively. REE speciation calculations using VMINTEQ program show REEs in simulated xylem solution mainly exist as REE-EDTA^(- )and RE^(3+), but only HREEs are enriched in REE-EDTA^(-), while LREEs are enriched in the other REE species. It is suggested that the fractionation between LREEs and HREEs might be caused by the uptake of REE-EDTA^(-) in Triticum aestivum leaves, but might result from the uptake of the other REE species in their stems.

关键词： fractionation lanthanides tetrad effect Triticum aestivum rare earths

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Mineralogy and Geochemistry of Uraniferous Sandstones in Fault Zone,Wadi El Sahu Area,Southwestern Sinai,Egypt:Implications for Provenance,Weathering and Tectonic Setting

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 830-845页

作者： Osama R.SALLAM Hamed IMIRA Amira M.El TOHAMY Abd Elhadi AABBAS Nuclear Materials Authority El-Maadi Cairo P.O.Box:530Egypt

Paleozoic rocks in the Wadi El Sahu area are affected by many major faults in different directions.A reverse fault trending NE-SW is exposed for about 300 m of its length as it cuts through the Abu Hamata and Adedia formations on the south side of Wadi El Sahu.A secondary ascending hydrothermal solution carrying heavy metals and radioactive minerals passed through the fault plain and the surrounding fractures,forming mineralized and radioactive *** mineralized zone thickness ranges from 60 cm to 200 cm along the fault *** rocks were analyzed radiometrically using a portable gamma-ray spectrometer,chemically by employing ICP-ES and ICP-MS,as well as mineralogically by both binocular and Environmental Scanning Electron *** content was also determined by fire *** and U contents reached up to 2682 and 1216 ppm,*** investigations indicated the presence of uraninite,torbernite,autunite,sklodowskite,kasolite as uranium minerals,thorite as a thorium mineral,monazite,allanite and xenotime as REE-bearing minerals,zircon and columbite as accessory minerals,gold and nickel as precious and base metals,in addition to cassiterite,chalcopyrite,chalcocite and *** REE and U contents are attributed to the circulation of epigenetic U and REE-bearing hydrothermal solutions along the fault plain and its surrounding *** alteration processes could then be confirmed by the presence of the M-type tetrad effect in the REE-patterns of the ferruginous *** non-chondritic ratio of Nb/Ta,Zr/Hf and Y/Ho in the studied sandstone may be attributed to the tetrad *** Ce and Eu anomaly with unusual REE-patterns was represented by the presence of conjugated M-W tetrad effects,indicating either the dual effect of hydrothermal solutions or groundwater with *** results clarify that the tetrad-effects could be used as evidence for the environment of deposition and as an indication for gold minerali

关键词： uranium gold RREs tetrad effect

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Geochemistry and Petrogenesis of Late Ediacaran Rare-metal Albite Granites of the Arabian-Nubian Shield

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 459-480页

作者： Bassam A.ABUAMARAH Mokhles K.AZER Paul D.ASIMOW Habes GHREFAT Heba S.MUBARAK Department of Geology and Geophysics King Saud UniversityRiyadh 11451Saudi Arabia Geological Sciences Department National Research CentreDokkiCairo 12622Egypt Division of Geological&Planetwy Sciences California Institute of TechnologyPasadena CA 91125USA

The Abu Dabbab albite granite(ADAG),in the central Eastern Desert of Egypt,hosts the most significant rare metal ore deposit in the northern part of the Neoproterozoic Arabian-Nubian ***,we report detailed field,petrographic,mineralogical and geochemical investigation of the ADAG,an isolated stock-like granitic body with sharp intrusive contacts against metamorphic country rocks,probably emplaced at about 600 *** fine-grained porphyritic upper unit is a preserved remnant of the shallowly-emplaced apex of the magma chamber,whereas the medium-grained lower unit crystallized at deeper levels under subvolcanic *** peraluminous leucocratic ADAG shares common geochemical characteristics with post-collisional intraplate A-type *** addition to the conspicuous enrichment in Na2O,the ADAG is remarkable for its anomalous concentrations of Ta,Nb,Li,Hf,Ga,Sn,Zn and heavy rare-earth ***-Ta minerals in the ADAG are mixed with Fe-Mn oxides,forming black patches that increase in abundance toward of the base of the ***-tantalite,cassiterite and wolframite are the most important ore *** negative Eu anomalies(Eu/Eu*=0.10–0.24)reflect extreme magmatic fractionation and perhaps the effects of late fluid-rock *** ADAG was most likely generated by partial melting of the juvenile middle crust of the ANS as the geotherm was elevated by erosional uplift following lithospheric delamination and it was emplaced at the intersection of lineations of structural *** formation of the ADAG and its primary enrichment in rare metals are essentially due to magmatic processes,late-stage metasomatism caused limited redistribution of rare ***-driven subsolidus modification was limited to the apex of the magma chamber and drove development of greisen,amazonite,and quartz veins along fracture systems.

关键词： amazonite greisen rare-metal bearing granite stockscheider pegmatite tetrad effect post-collisional Arabian-Nubian Shield

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Petrogenesis of early Yanshanian highly evolved granites in the Longyuanba area,southern Jiangxi Province:Evidence from zircon U-Pb dating,Hf-O isotope and whole-rock geochemistry

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Science China Earth Sciences 2013年第5期56卷 922-939页

作者： TAO JiHua LI WuXian LI XianHua CEN Tao State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Graduate University of Chinese Academy of Sciences State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences

Early Yanshanian(Jurassic) granitoids are widespread in the Nanling Range,South *** large granitic batholiths commonly crop out in the center of the Nanling Range(corresponding geographically to the central and northern parts of Guangdong Province),many small stocks occur in the southern part of Jiangxi *** of the small stocks are associated closely with economically significant rare-metal deposits(W,Sn,Nb,Ta).Here we report the results for biotite granites and two-mica granites from three Yanshanian stocks of the Longyuanba ***-ICPMS U-Pb dating of zircon yields an age of 156.1±2.1 Ma for Xiaomubei biotite granite,and U-Pb zircon dating using SIMS yields an age of 156.7±1.2 Ma for Longyuanba-Chengjiang biotite granite and 156.4±1.3 Ma for Jiangtoudong two-mica *** granites are silica-rich(SiO 2 =70%-79%),potassic(K 2 O/Na 2 O>1.9),and peraluminous(ASI=1.05-1.33).Associated samples are invariably enriched in Rb,Th,Pb and LREE,yet depleted in Ba,Nb,Sr,P and Ti,and their REE pattern shows a large fractionation between LREE and HREE((La/Yb) N =10.7-13.5) and a pronounced Eu negative anomaly(δEu=0.28-0.41).Two-mica granite samples are also silica-rich(SiO 2 =75%-79%),potassic(K 2 O/Na 2 O>1.2),and peraluminous(ASI=1.09-1.17).However,in contrast to the biotite granites,they are more enriched in Rb,Th,Pb and extremely depleted in Ba,Nb,Sr,P and Ti,and exhibit nearly flat((La/Yb) N =0.75-1.08) chondrite-normalized REE patterns characterized by strong Eu depletion(δEu=0.02-0.04) and clear tetrad effect(TE 1.3 =1.10-1.14).Biotite granites and two-mica granties have comparable Nd isotopic signatures,and their εNd(t) are concentrated in the 13.0 to 9.6 and 11.5 to 7.7 *** zircon Hf-O isotopes of both also show similarity(biotite granites:εHf(t)= 10.8-7.9,δ 18 O=7.98‰-8.89‰ and εHf(t)= 13.8 to 9.1,δ 18 O=8.31‰-10.08‰;two-mica granites:εHf(t)= 11.3 to 8.0,δ 18 O=7.91‰-9.77‰).The results show that both biotite and two-mica gra

关键词： highly evolved tetrad effect granite early Yanshanian southern Jiangxi Province

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Study on Interaction Energy of PAMAM/Lanthanide(Ⅲ) by Molecular Dynamics Method

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Journal of Rare Earths 2007年第2期25卷 129-134页

作者：莫尊理孙亚玲李贺军陈红刘艳芝 College of Chemistry and Chemical Engineering Northwest Normal University College of Material Science and Engineering Northwestern Polytechnical University

PAMAM/lanthanide （Ⅲ） nanocomposite was studied by molecular simulation method. Molecular simulation enabled study of the lanthanide tetrad effect at atomic level. However, PAMAM dendrimer exhibiting unique properties such as nanometer size and highly functionalized terminal surface provided a novel space for lanthanide （Ⅲ） to show their peculiar tetrad effect. The results showed that total energies of PAMAM/lanthanide（Ⅲ） nanocomposites presented obvious tetrad effect and special double-double effect. Nd, Gd, and Er fell to the lower point and Gd fell to the lowest point in the TE-Ln curve with four groups. In order to explain the tetrad effect, kinetic energy （KE） and potential energy （PE） were analyzed. The KE curve consisted of three W-type parts （La - Pm, Pm - Tb, Tb - Tm, and the latter two W-type part were axial symmetry） and an exception part （Yb - Lu）. It also showed that the KE of odd atomic number was higher than the even one＇s with exception of Yb and Lu. Furthermore, decomposed potential energies gave out the atomic-level subtle difference of lanthanide which present more regulations for Eu（Ⅲ） - Lu（Ⅲ） compared with La（Ⅲ） - Sm（Ⅲ）. And also Ho-valley and three platforms （Sm - Eu, Td - Dy, Er - Tm） were discovered that refect the regular change of nanocomposite structures. Additionally, there are distinct correlations between Ebond and EInversion, EAngle and EVDW, Eworsion and ECoul, respectively. Therefore, PAMAM could be used in separation of lanthanide by changing conditions.

关键词： molecular simulation tetrad effect PAMAM lanthanide nanocomposite rare earths

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Petrological and Geochemical Constraints on the Evolution of EI-Kahfa Alkaline Ring Complex, South Eastern Desert, Egypt

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Journal of Geological Resource and Engineering 2016年第6期4卷 283-304页

作者： A. M. Bishady A. M. EI-Sherif M. E. Darwish Geol. Dept. Fae. Sci. Menoufiya Univ. Shebin El-Kom Egypt Nuclear Materials Authority Cairo Post Office Box No. 530 Maadi Egypt

El-Kahfa complex locates at the intersection of Lat. 24°8′18″ N and Long. 34038′55″ E, South Eastern Desert of Egypt. It comprises an outer ring composed of alkaline syenites, ranging from barrento quartz-bearing syenites, an inner ring which varies in composition from leucocratic to melanocratic syenites, and a central stock formed essentially of alkali gabbros. These alkali gabbros are cut by small bodies of alkaline syenites, which occasionally grade into nepheline syenites. The country rocks are represented mainly by metavolcanics and epidiorites. El-Kahfa syenites lack any primary hydrous mafic silicates indicating that their magma was anhydrous. Major and trace elements geochemistry of EI-Kahfa rocks reflects the crystallization of early plagioclase followed by Fe-Ti oxides. Salic members in the complex are co-magmatic and related to crystal liquid fractionation. The REE （rare earth elements）＇s tetrad is obvious on the primitive mantle normalized pattern of El-Kahfa rocks. The M-type tetrads clearly appear in the more evolved rocks. These tetrad effects are either a feature of magma-fluid system before crystallization or inherited from external fluid during or after the emplacement of the magma. Generally, El-Kahfa rocks parental magma was probably derived from Nb-enriched or at least under-plate mantle source within the continental East-Africa rift zone, where it may be subjected to minor contamination through their fractional crystallization.

关键词： Ring complex EI-Kahfa tetrad effect South Eastern Desert.

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