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Polyelectrolytes ability in reducing atrazine concentration in water: surface effects.

Mohd Amin MF, Heijman SG, Lopes SI, Rietveld LC - ScientificWorldJournal (2014)

Bottom Line: This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water.The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments.However, in this study, the conventional type of isotherm was not observed.

View Article: PubMed Central - PubMed

Affiliation: Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands ; Faculty of Earth Science, Universiti Malaysia Kelantan,, UMK Kampus Jeli, 17600 Jeli, Kelantan, Malaysia.

ABSTRACT
This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism.

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Related in: MedlinePlus

Isotherm of atrazine reduction by 71305 and starch based on SVR (1.8, 0.7, and 0.4 m−1).
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Related In: Results  -  Collection


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fig4: Isotherm of atrazine reduction by 71305 and starch based on SVR (1.8, 0.7, and 0.4 m−1).

Mentions: In accordance with theory and hypotheses already mentioned, we expect that the glass surface area will affect the atrazine reduction (Figures 3 and 4). To prove this effect of the surface-to-volume ratio, an experiment on the effect of the SVR on atrazine reduction was performed. Figure 3 shows that, with an increase in the SVR, a higher atrazine reduction from the solution occurred before the reduction became constant. With the charge differences between the glass surface (negative) [15] and the polymer (positive), adsorption of polymers to the surface was expected to occur. The adsorption and polymer layer formation on the surface were justified by a lower atrazine concentration reduction with a decrease in the SVR. In relation to the isotherms in Figures 1 and 2, this then resulted in a steep increase in the isotherm and a nearly constant reduction of atrazine. As the SVR increased the glass surface can easily become saturated with polymer molecules. The polymer then has to compete for surface sites. Fleer et al. [16] also reported this phenomenon.


Polyelectrolytes ability in reducing atrazine concentration in water: surface effects.

Mohd Amin MF, Heijman SG, Lopes SI, Rietveld LC - ScientificWorldJournal (2014)

Isotherm of atrazine reduction by 71305 and starch based on SVR (1.8, 0.7, and 0.4 m−1).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4150508&req=5

fig4: Isotherm of atrazine reduction by 71305 and starch based on SVR (1.8, 0.7, and 0.4 m−1).
Mentions: In accordance with theory and hypotheses already mentioned, we expect that the glass surface area will affect the atrazine reduction (Figures 3 and 4). To prove this effect of the surface-to-volume ratio, an experiment on the effect of the SVR on atrazine reduction was performed. Figure 3 shows that, with an increase in the SVR, a higher atrazine reduction from the solution occurred before the reduction became constant. With the charge differences between the glass surface (negative) [15] and the polymer (positive), adsorption of polymers to the surface was expected to occur. The adsorption and polymer layer formation on the surface were justified by a lower atrazine concentration reduction with a decrease in the SVR. In relation to the isotherms in Figures 1 and 2, this then resulted in a steep increase in the isotherm and a nearly constant reduction of atrazine. As the SVR increased the glass surface can easily become saturated with polymer molecules. The polymer then has to compete for surface sites. Fleer et al. [16] also reported this phenomenon.

Bottom Line: This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water.The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments.However, in this study, the conventional type of isotherm was not observed.

View Article: PubMed Central - PubMed

Affiliation: Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2628 CN Delft, The Netherlands ; Faculty of Earth Science, Universiti Malaysia Kelantan,, UMK Kampus Jeli, 17600 Jeli, Kelantan, Malaysia.

ABSTRACT
This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism.

Show MeSH
Related in: MedlinePlus