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Removal of Cr(VI) from aqueous environments using micelle-clay adsorption.

Qurie M, Khamis M, Manassra A, Ayyad I, Nir S, Scrano L, Bufo SA, Karaman R - ScientificWorldJournal (2013)

Bottom Line: Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions.Langmuir adsorption isotherm fitted the experimental data giving significant results.The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Chemical Technology, Faculty of Science and Technology, Al-Quds University, 20002 Jerusalem, Palestine ; Department of Science, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy.

ABSTRACT
Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques.

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Removal of chromium by micelle-clays complex as total-Cr determined by AAS (■) and as Cr(VI) determined by UV-vis method (♦). Percent of Cr(VI) reduction to Cr(III) (●) is calculated as the difference between total-Cr and Cr(VI) percentages. pH = 6, contact time = 3 h, temperature = 25.0 ± 0.2°C, and adsorbent dosage = 5.0 g L−1. Data represent averages of triplicates ± SE.
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fig3: Removal of chromium by micelle-clays complex as total-Cr determined by AAS (■) and as Cr(VI) determined by UV-vis method (♦). Percent of Cr(VI) reduction to Cr(III) (●) is calculated as the difference between total-Cr and Cr(VI) percentages. pH = 6, contact time = 3 h, temperature = 25.0 ± 0.2°C, and adsorbent dosage = 5.0 g L−1. Data represent averages of triplicates ± SE.

Mentions: Figure 3 shows that at pH 6 the reduction of Cr(VI) occurs at concentration larger than 50 mg L−1 and that it is more pronounced than that ascertained at pH 2. On the contrary, in the samples kept without the adsorbent, no appreciable reduction of Cr(VI) to Cr(III) was ascertained at both pH values. The most remarkable observation is that up to pH 6 a total removal of Cr(VI) can be attained at concentration less than 50 mg L−1.


Removal of Cr(VI) from aqueous environments using micelle-clay adsorption.

Qurie M, Khamis M, Manassra A, Ayyad I, Nir S, Scrano L, Bufo SA, Karaman R - ScientificWorldJournal (2013)

Removal of chromium by micelle-clays complex as total-Cr determined by AAS (■) and as Cr(VI) determined by UV-vis method (♦). Percent of Cr(VI) reduction to Cr(III) (●) is calculated as the difference between total-Cr and Cr(VI) percentages. pH = 6, contact time = 3 h, temperature = 25.0 ± 0.2°C, and adsorbent dosage = 5.0 g L−1. Data represent averages of triplicates ± SE.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814082&req=5

fig3: Removal of chromium by micelle-clays complex as total-Cr determined by AAS (■) and as Cr(VI) determined by UV-vis method (♦). Percent of Cr(VI) reduction to Cr(III) (●) is calculated as the difference between total-Cr and Cr(VI) percentages. pH = 6, contact time = 3 h, temperature = 25.0 ± 0.2°C, and adsorbent dosage = 5.0 g L−1. Data represent averages of triplicates ± SE.
Mentions: Figure 3 shows that at pH 6 the reduction of Cr(VI) occurs at concentration larger than 50 mg L−1 and that it is more pronounced than that ascertained at pH 2. On the contrary, in the samples kept without the adsorbent, no appreciable reduction of Cr(VI) to Cr(III) was ascertained at both pH values. The most remarkable observation is that up to pH 6 a total removal of Cr(VI) can be attained at concentration less than 50 mg L−1.

Bottom Line: Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions.Langmuir adsorption isotherm fitted the experimental data giving significant results.The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Chemical Technology, Faculty of Science and Technology, Al-Quds University, 20002 Jerusalem, Palestine ; Department of Science, University of Basilicata, Via dell'Ateneo Lucano 10, 85100 Potenza, Italy.

ABSTRACT
Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques.

Show MeSH
Related in: MedlinePlus