In oxidizing environments the toxic and radioactive element uranium is most soluble and mobile in the hexavalent oxidation state. These processes also affect the biological availability of U(VI) species toward reduction and precipitation as the less soluble U(IV) species by metal-reducing bacteria.
Cited by 497 Chat Online· Recent work has shown that U can become incorporated into iron (hydr)oxide minerals with a key pathway arising from Fe (II)-induced transformation of ferrihydrite (Fe (OH) 3 ·nH 2 O) to goethite (α-FeO (OH)) this is a possible U retention mechanism in soils and sediments.
Cited by 54 Chat Online· through precipitation of iron on the zeolite. The kinetic data for As(V) adsorption by iron (hydr) oxide-modified zeolite model fit well into pseudo second-order and the adsorption capacity was obtained as -0.080 mg g. 1. The application of iron (hydr) oxide modified zeolite on AMD for As(V) recovery showed that > 99 of As(V)
Chat Online· Iron(III) oxide minerals are insoluble and so are heavy metals and metalloids through co-precipitation or J. C. Enzymatic iron and uranium reduction by sulfate-reducing bacteria.
Chat Online· Duff MC Coughlin JU Hunter DB (2002) Uranium co-precipitation with iron oxide minerals. Geochim Cosmochim Acta 66 3533–3547. CAS Article Google Scholar 48. Qian L Ma M Cheng D (2015) Adsorption and desorption of uranium on nano goethite and nano alumina. J Radioanal Nucl Chem 303 161–170
Chat OnlineUranium tends to co-precipitate with Fe 35 36 and therefore there may also be an effect of Fe–U co-precipitation at the surface of the sandstone. However thermodynamic modelling including the concentrations of elements released into solution does not predict the precipitation of any Fe–U minerals.
Chat Online· uranium (U) towards reduction to the less soluble U(IV) species may be lim-ited by co-precipitation with Fe-oxide minerals. We examined the interac-tion dynamics between U(VI) and iron (Fe) oxides during crystallization by synthesizing Fe-oxide phases 0.5-5.4 mole U/(U
Chat OnlineIn oxidizing environments the toxic and radioactive element uranium (U) is most soluble and mobile in the hexavalent oxidation state. Sorption of U(VI) on Fe-oxides minerals (such as hematite α-Fe 2 O 3 and goethite α-FeOOH ) and occlusion of U(VI) by Fe-oxide coatings are processes that can retard U transport in environments. In aged U-contaminated geologic materials the transport and the biological availability of U toward reduction may be limited by coprecipitation with Fe-oxide
Cited by 497 Chat OnlineDownload PDF Sorry we are unable to provide the full text but you may find it at the following location(s) https //digital.library.unt.ed (external link)
Chat Online5 Uranium co-precipitation with iron oxides The mechanism of uranium uptake from aqueous phases by secondary iron minerals (oxides hydroxidesiron corrosion products) was investigated with laboratory experiments. For this purpose aqueous uranium solutions were allowed to react with a scrap iron (metallic ironFe0).
Chat OnlineIron hydroxy oxide-based materials strongly adsorb uranyl species between pH 5 and 10. The compounds haematite (a-Fe2O3) geothite (a-FeOOH) and ferrihydrite (pseudo-amorphous Fe2O3 xH2O) are thought to be among the most important in this regard but Lenhart Honeyman (1999) have also considered the role of humic acids in their models.
Estimated Reading Time 11 minsChat Online· 2002 Uranium co-precipitation with iron oxide minerals. Geochim. Cosmochim. Acta. 66 3533–3547. Crossref Google Scholar
Cited by 30 Chat OnlineBiogeochemical retention processes including adsorption reductive precipitation and incorporation into host minerals are important in contaminant transport remediation and geologic deposition of uranium. Recent work has shown that U can become incorporated into iron (hydr)oxide minerals with a key pathway arising from Fe(II)-induced transformation of ferrihydrite (Fe(OH)3
Chat OnlineImmobilization of uranium by reductive precipitation can be divided into two mechanistic phases. The initial rapid reaction involves reduction of uranium at the steel surface. The secondary phase involves reductive precipitation of uranium by dissolved Fe(II) co-precipitating uranium oxide and iron oxyhydroxide phases onto the surface deposit.
Chat OnlineThe Zoovch Ovoo uranium deposit is located in East Gobi Basin in Mongolia. It is hosted in the Sainshand Formation a Late Cretaceous siliciclastic reservoir in the lower part of the post-rift infilling of the Mesozoic East Gobi Basin. The Sainshand Formation corresponds to poorly consolidated medium-grained sandy intervals and clay layers deposited in fluvial-lacustrine settings.
Chat Online· performed by an iron oxide and barium sulfate precipitation unit leading to arsenic and radium retention by co-precipitation and adsorption. Fig. 1 depicts a flow chart of the WTP. Briefly the precipitation plant treatment scheme comprises aeration addition of chemicals mixing coagulation
Chat OnlineImmobilization of uranium by reductive precipitation can be divided into two mechanistic phases. The initial rapid reaction involves reduction of uranium at the steel surface. The secondary phase involves reductive precipitation of uranium by dissolved Fe(II) co-precipitating uranium oxide and iron oxyhydroxide phases onto the surface deposit.
Chat Online· 2002 Uranium co-precipitation with iron oxide minerals. Geochim. Cosmochim. Acta. 66 3533–3547. 2001 Uranium precipitation in a permeable reactive barrier by progressive irreversible dissolution of zero-valent iron. J. Environ. Sci. Technol. 35 385–390.
Chat Online· 24 Despite this detailed mechanistic information regarding the incorporation of uranium into 25 Fe(II) bearing magnetite and green rust is sparse. Here we present a co-precipitation study 26 where U(VI) was reacted with environmentally relevant iron(II/III) (oxyhydr)oxide mineral 27 phases.
Chat Online· 24 Despite this detailed mechanistic information regarding the incorporation of uranium into 25 Fe(II) bearing magnetite and green rust is sparse. Here we present a co-precipitation study 26 where U(VI) was reacted with environmentally relevant iron(II/III) (oxyhydr)oxide mineral 27 phases.
Chat Online· often co-crystallize with iron oxides or hydroxides. Iron oxides especially hematite are ideal minerals for uranium uptake because of their high sorption capacity (e.g. surface adsorption) ubiquity and redox sensitivity (Stewart et al. 2009 Marshal et al. 2014). In U- and Fe-rich environments both incorporation of U into the iron
Chat OnlineThe Zoovch Ovoo uranium deposit is located in East Gobi Basin in Mongolia. It is hosted in the Sainshand Formation a Late Cretaceous siliciclastic reservoir in the lower part of the post-rift infilling of the Mesozoic East Gobi Basin. The Sainshand Formation corresponds to poorly consolidated medium-grained sandy intervals and clay layers deposited in fluvial-lacustrine settings.
Chat OnlineBy Martine C. Duff Jessica Urbanik Coughlin Douglas B. Hunter Allard Allen Azenha Bargar Bargar Batson Bertsch Biwer Blake Bruno Buck Burns Chao
Chat Online· 4. Analysis of uranium from associated minerals Often uranium content is correlated to amount of other minerals that occur in higher amounts or are easier to detect with XRF method. In different ore bodies these may be minerals of Pb Mo Cu Co Ni Bi Sn Ag and other elements.
Chat OnlineDownload PDF Sorry we are unable to provide the full text but you may find it at the following location(s) https //digital.library.unt.ed (external link)
Chat OnlineBy Martine C. Duff Jessica Urbanik Coughlin Douglas B. Hunter Allard Allen Azenha Bargar Bargar Batson Bertsch Biwer Blake Bruno Buck Burns Chao
Chat Online· around pH 7 may be due to the surface precipitation of Co(OH)2 James and Healy 4 . on the basis of their electrokinetic potential measurements have shown that the surface of silica under these conditions becomes similar to t at of Co(OH)2 According to these authors oxide minerals in general in
Chat OnlineUranium may also be retained through incorporation within the structure of other host minerals. For example Pett-Ridge et al. (2007) concluded that non-exchangeable U in 150–4100 ka Hawaiian soils was co-precipitated with Fe to form iron oxides and Sato et al. (1997) showed that iron oxides scavenged greater than 8 U (by weight) from
Chat OnlineBiogeochemical retention processes including adsorption reductive precipitation and incorporation into host minerals are important in contaminant transport remediation and geologic deposition of uranium. Recent work has shown that U can become incorporated into iron (hydr)oxide minerals with a key pathway arising from Fe(II)-induced transformation of ferrihydrite (Fe(OH)3
Chat OnlineUranium co-precipitation with iron oxide minerals Martine C. Duff Jessica Urbanik Coughlin Douglas B. Hunter
Chat OnlineAn important problem in the mineral processing industry is the removal of iron (III) from process and waste streams by precipitation as the metal hydroxide by elevation of pH. Caustic (NaOH) lime(CaO) and slaked lime (Ca(OH)2 ) are cheap and effective reagents for this purpose however iron (III) oxyhydroxides often form polymeric chains when precipitated at ambient temperature.
Chat OnlineDownload PDF Sorry we are unable to provide the full text but you may find it at the following location(s) https //digital.library.unt.ed (external link)
Chat Online· Iron(III) oxide minerals are insoluble and so are heavy metals and metalloids through co-precipitation or J. C. Enzymatic iron and uranium reduction by sulfate-reducing bacteria.
Chat OnlineDownload PDF Sorry we are unable to provide the full text but you may find it at the following location(s) https //digital.library.unt.ed (external link)
Chat OnlineBy Martine C. Duff Jessica Urbanik Coughlin Douglas B. Hunter Allard Allen Azenha Bargar Bargar Batson Bertsch Biwer Blake Bruno Buck Burns Chao
Chat Online· 24 Despite this detailed mechanistic information regarding the incorporation of uranium into 25 Fe(II) bearing magnetite and green rust is sparse. Here we present a co-precipitation study 26 where U(VI) was reacted with environmentally relevant iron(II/III) (oxyhydr)oxide mineral 27 phases.
Cited by 34 Chat Online· often co-crystallize with iron oxides or hydroxides. Iron oxides especially hematite are ideal minerals for uranium uptake because of their high sorption capacity (e.g. surface adsorption) ubiquity and redox sensitivity (Stewart et al. 2009 Marshal et al. 2014). In U- and Fe-rich environments both incorporation of U into the iron
Chat OnlineBy Martine C. Duff Jessica Urbanik Coughlin Douglas B. Hunter Allard Allen Azenha Bargar Bargar Batson Bertsch Biwer Blake Bruno Buck Burns Chao
Chat Online