M Rasooli Bairami; B Shafiei Bafti; J Omrani; F Heydarian
Abstract
The occurrence of uranium anomalies associated with secondary Cu mineralization (malachite) at some parts of the Razgah metaluminous -peralkaline stock situated at the northeast of Sarab caused it to be a priority of Atomic Energy Organization of Iran (AEOI) to inspect the intrusion for likely uranium ...
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The occurrence of uranium anomalies associated with secondary Cu mineralization (malachite) at some parts of the Razgah metaluminous -peralkaline stock situated at the northeast of Sarab caused it to be a priority of Atomic Energy Organization of Iran (AEOI) to inspect the intrusion for likely uranium mineralization. Hence the current study, which is supervised by AEOI, was carried out to investigate the U mineralization potential of the stock by applying the mineralogical, petrological and geochemical studies. A fractionation trend is inferred from variations in rock compositions stretching from nepheline-bearing monzodiorite to nepheline monzosyenite, pseudoleucite monzosyenite and nepheline syenite. Consideration of geochemical features of fresh rocks of the stock and its associated dikes with emphasis on geochemical behavior of U and REEs during magmatic fractionation revealed that apatite has played a prominent role in controlling concentrations of REEs, U, and Th, in addition to zircon, which played a considerable role in accommodating HREEs, U, Th and HFSEs (Ti, Ta, Nb, Hf, Zr) in more differentiated rocks.Nepheline syenite rocks of peralkaline composition,s which are considered to be the most differentiated have low contents of HFSEs, U (up to 21 ppm), Th (up to 56 ppm) and REEs compared to average nepheline syenites but are relatively more enriched in these elements than less differentiated rocks of the stock. Most of the rocks possess negative Eu anomalies (Eu/Eu*≤1) and differentiated nepheline syenites have strong negative Eu anomalies. Abundance of ilmenite and magnetite and lack of amphibole in rocks suggests the parental magma had a reducing nature and meagre contents of volatile components, which along with metaluminous character and prepondarence of apatite in rocks have rendered the magma incapable of enriching U. Minor amounts of hydrothermal fluids released from some parts of the stock led to leaching of U from hosting minerals (apatite and zircon) and resulted in weak hypogene mineralization of U and Cu. Later supergene leaching process affected the weak primary mineralization and upgraded U tenors concurrent with formation of secondary Cu carbonate minerals. Due to thin and limited extention of these enrichment sites, they are not economically viable for uranium extraction; consequently, this area does not suggest for semi-detailed and detailed exploration program for uranium by AEOI.
S Veyseh; A Rajabi Khorrami
Abstract
The purpose of this paper is to analyze geological samples (water) using cartridge in order to pre- concentration of these samples. In this paper, the study of Uranium ion imprinted polymer (IIP) synthesis is addressed. The Uranium ion complex in (CH3Coo) 2 Uo2 .2H2O is considered as the initial nucleus ...
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The purpose of this paper is to analyze geological samples (water) using cartridge in order to pre- concentration of these samples. In this paper, the study of Uranium ion imprinted polymer (IIP) synthesis is addressed. The Uranium ion complex in (CH3Coo) 2 Uo2 .2H2O is considered as the initial nucleus of polymer. This complex is formed by di vinyl phosphonic acid (VIP) ligand. Then, ethylene glycol dimethacrylate (EGDMA) is used as cross linker and azobis isobutyronitril (AIBN) acting as initiator in polymerization is applied for the final synthesis of polymer. The synthesis of these polymers is performed by covalent interactions. The complex of non- imprinted polymer (NIP) is also synthesized under above- mentioned condition but without the presence of Uranium ion and ligand. IIP was obtained can be used as a high absorbent for solid phase extraction (IIP-SPE). In addition, the study of condition and tests such as pH effect on absorption, permeability factor, acid concentration and volume which is required for elution is conducted in order to test the column efficiency. The experimental evidences indicate that the maximum absorption of Uranium ion is in pH= 7. In addition, 1M nitric acid solution with 5 ml volume has the highest elution rate. The rate of uranium permeation was measured above 200 mm. The results were obtained by ICP-MS as reference and ICP-OES to promote the analytical reading and reduce the detection limit. These results indicate very high absorption of IIP for Uranium ions. It must be noted that this process was successfully applied for pre-concentration of geological samples, in particular water samples and led to the promotion of results from analyzing all metallic ions such as uranium ion in geological samples (water) by ICP-OES and analytical optimization with lower detection limit by ICP-MS.
M. Pakdel; B. Rezai; R. Asgari; K. Nazari
Abstract
Magnetic and electrostatic properties of minerals are the important characterizations used in mineral processing technology for concentration of minerals. Mineralogy and degree of liberation of the ore with a uranium average content of 1540 ppm, has been studied ...
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Magnetic and electrostatic properties of minerals are the important characterizations used in mineral processing technology for concentration of minerals. Mineralogy and degree of liberation of the ore with a uranium average content of 1540 ppm, has been studied by XRD and microscopic methods. Major minerals such as alkali feldspar (Orthoclase), plagioclase (Albite), biotite, chlorite, carbonate and minor minerals such as sphene, zircon, actinolite, tremolite, pitchblende and betafite have been identified in this ore. Additionally, the degree of liberation of orthoclase, albite, biotite and uranium minerals was determined 320, 290, 190 and 110 microns respectively. Based on the results of mineralogy and degree of liberation studies, magnetic and electrostatic tests have been performed on fractions: -420+250, -250+125 and -125+74 microns. High intensity magnetic tests in two ways, wet and dry separations were done by HIMS separator and plate separator. Analyses of magnetic test results showed that the separation has low recovery. Recovery for dry and wet methods was 45.03 and 26.99% respectively. Analyses of electrostatic test results showed that the maximum recovery of these tests is 51.36% uranium and in this state 27.63% uranium in 42.02 weight percent of feed is rejected. Generally, the recovery of these separations was low, so these methods are not suitable for concentration of this ore.
