Uranium removal from groundwater by natural clinoptilolite zeolite: Effects of pH and initial feed concentration

Camacho, Lucy Mar; Deng, Shuguang; Parra, R.

doi:10.1016/j.jhazmat.2009.10.017

Cited by 261 publications

(61 citation statements)

References 25 publications

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“…Uranium is in the common range of pH = 6-8 present in the form of anion UO 2 (CO 3 ) 2 2-, and consequently, should be removed by anion exchange through strong basic anionite (SBA) [5,6]. An alternative to ion exchange process is reverse osmosis [7].…”

Section: Technology For Radionuclides Removalmentioning

confidence: 99%

Radioactivity of Estonian groundwater and technology for its removal

Lumiste

Munter

Sutt³

et al. 2012

Water Pollution XI

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The purpose of this work has been to elaborate a cost-effective and relatively simple technology for groundwater simultaneous purification from iron, manganese, sulfides, ammonia, and some radionuclides (Rn 222 , Ra 226 , Ra 228 ). A pilot plant consisting of the Venturi-type aeration unit GDT (Gas-Degas Technology, Mazzei Corp. USA), an oxidation tank and two-stage filtration columns was constructed. Different non-catalytic (Everzit Special Plus, sand etc.) and catalytic filter materials (Filtrasorb FMH, Pyrolox etc.) as well as zeolites were tested. It was found that intensive aeration of groundwater, followed by oxidation with certain contact time, and appropriate selection of filter materials of different properties, enable removal of radium isotopes together with iron and manganese. Total effectiveness of the process was 90% removal of gross-alfa and 70-75% removal of gross-beta activity of groundwater. The total average effective dose was calculated by residual Ra 226 and Ra 228, and was about 0.07 mSv/yr, which meets the EU DWD requirement (0.1 mSv/yr). On the basis of the results of the pilot plant studies, a full scale plant (2500 m 3 /d) of Viimsi Water Ltd. was designed by the SWECO Project. The plant will be put into operation in January 2012.

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Section: Technology For Radionuclides Removalmentioning

confidence: 99%

Radioactivity of Estonian groundwater and technology for its removal

Lumiste

Munter

Sutt³

et al. 2012

Water Pollution XI

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“…3a, the maximal uranium sorption capacity of 84.85 mg/g was reached for solutions of initial concentration of 5.95 mg/L at pH 6.5, suggesting a good performance at near-neutral pH, which increases the likelihood of using them as uranium(VI) sorbents in natural water. The results should be attributed to the strong complex of uranium(VI) with amidoxime group at pH 6.5 via ligand exchanges [36,37]. The effect of sorbent dose on the sorption was studied with dosage range from 25 to 125 mg/L at pH 6.5 (Fig.…”

Section: Resultsmentioning

confidence: 99%

Synthesis of polyamidoxime-functionalized nanoparticles for uranium(VI) removal from neutral aqueous solutions

Huang

Zhang²,

Hua

2015

J Radioanal Nucl Chem

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It is important to separate uranium(VI) from water environment due to its high toxicity and radioactivity. A new kind of polystyrene nanoparticles with polyamidoxime is reported here for removal of uranium(VI) from aqueous solutions. The obtained PSt nanoparticles have a tunable sorption capacity. The sorption process follows pseudo-second-order kinetics, and the equilibrium can be reached within 6 h. Furthermore, the optimal pH value of sorption process is 6.5, and the adsorbents can be recycled well for uranium(VI) sorption from aqueous solution. This work indicates that the polyamidoxime-functionalized PSt nanoparticles may be used as a good adsorbent for the removal of uranium(VI) from neutral aqueous solution.

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“…Figure 2 also shows the euhedral nature of zeolites (phillipsite). Zeolites that have a channel like structure and high cation exchange capacity (CEC) can act as molecular sieves [13]. Figure 3 illustrates the microporous texture and large surface area of porcelanite.…”

Section: Xrf and Sem Measurementsmentioning

confidence: 99%

“…Heavy metals removal efficiency by montmorillonitic and calcareous clays has been correlated to the amount of calcium carbonates present in the samples [12]. Zeolites have been successfully used to remove uranium (IV) from contaminated waters [13] and oil from palm oil mill effluent [14].…”

Section: Introductionmentioning

confidence: 99%

Removal of Pb(II) from Aqueous Solutions by Zeolites, Porcelanite and Sands: Correlation of Morphology and Chemical Composition to Batch Removal Efficiency

Jumean¹,

Pappalardo²,

Khoury³

2015

AJAC

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Chemical compositions of natural zeolites, porcelanite (opal-CT) and local sands were determined by X-ray fluorescence (XRF) and correlated with their Pb(II) removal efficiencies. Zeolites and porcelanite were from the Mikawer, Aritain and Hannon areas in Jordan. Sands (white, red and yellow) were from the United Arab Emirates (UAE). The effect of Pb(II) concentration and zeolite dosage on removal efficiency was investigated at 25.0˚C using the batch equilibrium method. Commercial kaolinite, silica and alumina were also studied for comparison. Removal efficiencies, in mg Pb(II)/g adsorbent, were: 76.9, 52.7 and 42.1 for Hannon, Mikawer and Aritain zeolites, respectively; 58.2 for porcelanite; 29.7, 11.0 and 8.5 for yellow, red and white sand, respectively; 7.2, 3.3 and 1.3 for kaolinite, silica and alumina, respectively. XRF data indicate that adsorbents with intermediate molar ratios of Si/Al, in the range 2.70 -2.93, are most efficient in Pb(II) removal. Scanning electron microscope (SEM) images of adsorbents suggest that morphology, in addition to chemical composition, plays a key role. In particular, a combination of factors, including shapes and sizes of crystals, channels in zeolites and pores in porcelanite, appear to favor removal of Pb(II).

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Uranium removal from groundwater by natural clinoptilolite zeolite: Effects of pH and initial feed concentration

Cited by 261 publications

References 25 publications

Radioactivity of Estonian groundwater and technology for its removal

Radioactivity of Estonian groundwater and technology for its removal

Synthesis of polyamidoxime-functionalized nanoparticles for uranium(VI) removal from neutral aqueous solutions

Removal of Pb(II) from Aqueous Solutions by Zeolites, Porcelanite and Sands: Correlation of Morphology and Chemical Composition to Batch Removal Efficiency

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