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Synthesis of Quercetin Loaded Nanoparticles Based on Alginate for Pb(II) Adsorption in Aqueous Solution.

Qi Y, Jiang M, Cui YL, Zhao L, Zhou X - Nanoscale Res Lett (2015)

Bottom Line: Characterization of AN and Q-AN were analysed by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffractometer (XRD), and thermogravimetric analysis (TG-DTG-DSC).AN and Q-AN, with a diameter of 95.06 and 58.23 nm, were constituted by many small primary nanoparticles.AN and Q-AN would probably be applied as adsorbents to remove Pb(II) and then recover it from wastewater for the advantages of simple preparation, high adsorption capacity, and recyclability.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin, 300072, China. qiyun@tju.edu.cn.

ABSTRACT
Pb(II) is a representative heavy metal in industrial wastewater, which may frequently cause serious hazard to living organisms. In this study, comparative studies between alginate nanoparticles (AN) and quercetin-decorated alginate nanoparticles (Q-AN) were investigated for Pb(II) ion adsorption. Characterization of AN and Q-AN were analysed by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffractometer (XRD), and thermogravimetric analysis (TG-DTG-DSC). The main operating conditions such as pH, initial concentration of Pb(II), and co-existing metal ions were also investigated using a batch experiment. AN and Q-AN, with a diameter of 95.06 and 58.23 nm, were constituted by many small primary nanoparticles. It revealed that when initial concentration of Pb(II) is between 250 and 1250 mg L(-1), the adsorption rate and equilibrium adsorption were increased with the increase of pH from 2 to 7. The maximum adsorption capacities of 147.02 and 140.37 mg L(-1) were achieved by AN and Q-AN, respectively, with 0.2 g adsorbents in 1000 mg L(-1) Pb(II) at pH 7. The adsorption rate of Pb(II) was little influenced by the co-existing metal ions, such as Mn(II), Co(II), and Cd(II). Desorption experiments showed that Q-AN possessed a higher desorption rate than AN, which were 90.07 and 83.26 %, respectively. AN and Q-AN would probably be applied as adsorbents to remove Pb(II) and then recover it from wastewater for the advantages of simple preparation, high adsorption capacity, and recyclability.

No MeSH data available.


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a The effect of pH on the adsorption of Pb(II) ions; the initial concentration of Pb(II) ions was 500 mg L−1. b The effect of pH on the Zeta potential of AN and Q-AN; the initial concentration of Pb(II) ions was 500 mg L−1. c The effect of initial Pb(II) concentration on the adsorption of Pb(II); the initial pH was 7. d The effect of initial Pb(II) concentration on the equilibrium adsorption of Pb(II); the initial pH was 7
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Fig4: a The effect of pH on the adsorption of Pb(II) ions; the initial concentration of Pb(II) ions was 500 mg L−1. b The effect of pH on the Zeta potential of AN and Q-AN; the initial concentration of Pb(II) ions was 500 mg L−1. c The effect of initial Pb(II) concentration on the adsorption of Pb(II); the initial pH was 7. d The effect of initial Pb(II) concentration on the equilibrium adsorption of Pb(II); the initial pH was 7

Mentions: As shown in Fig. 4a, the Pb(II) adsorption rate increased from 33.66 to 82.74 % for AN and 42.46 to 84.52 % for Q-AN with the increase of pH from 2 to 7 (Eq. (1)). It was known that Pb2+, Pb(OH)+, Pb(OH)20, and Pb(OH)3− were frequently found in aqueous solution [31]. In acidic medium, Pb2+ was the major lead species. And a small portion of Pb(OH)+ was present with the pH increased to neutral condition [32]. At low pH, a high H+ concentration competed with Pb(II) cations for active sites on the surface of AN and Q-AN. Besides, the surface of AN and Q-AN turned into a negative charge when pH increased [33–35]. And it was confirmed by estimating the Zeta potential of AN and Q-AN at pH 2–7. Figure 4b indicates an obvious decrease of Zeta potential from −1.41 to −32.94 mV (AN) and −1.99 to −44.70 mV (Q-AN) when pH enhanced from 2 to 7. Namely, the more negative the nanoparticles are charged, the stronger is the electrostatic attraction between them and Pb(II). Therefore, an increasing acidic medium facilitated Pb(II) adsorption by affecting both the lead species and adsorbent surface.Fig. 4


Synthesis of Quercetin Loaded Nanoparticles Based on Alginate for Pb(II) Adsorption in Aqueous Solution.

Qi Y, Jiang M, Cui YL, Zhao L, Zhou X - Nanoscale Res Lett (2015)

a The effect of pH on the adsorption of Pb(II) ions; the initial concentration of Pb(II) ions was 500 mg L−1. b The effect of pH on the Zeta potential of AN and Q-AN; the initial concentration of Pb(II) ions was 500 mg L−1. c The effect of initial Pb(II) concentration on the adsorption of Pb(II); the initial pH was 7. d The effect of initial Pb(II) concentration on the equilibrium adsorption of Pb(II); the initial pH was 7
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4608953&req=5

Fig4: a The effect of pH on the adsorption of Pb(II) ions; the initial concentration of Pb(II) ions was 500 mg L−1. b The effect of pH on the Zeta potential of AN and Q-AN; the initial concentration of Pb(II) ions was 500 mg L−1. c The effect of initial Pb(II) concentration on the adsorption of Pb(II); the initial pH was 7. d The effect of initial Pb(II) concentration on the equilibrium adsorption of Pb(II); the initial pH was 7
Mentions: As shown in Fig. 4a, the Pb(II) adsorption rate increased from 33.66 to 82.74 % for AN and 42.46 to 84.52 % for Q-AN with the increase of pH from 2 to 7 (Eq. (1)). It was known that Pb2+, Pb(OH)+, Pb(OH)20, and Pb(OH)3− were frequently found in aqueous solution [31]. In acidic medium, Pb2+ was the major lead species. And a small portion of Pb(OH)+ was present with the pH increased to neutral condition [32]. At low pH, a high H+ concentration competed with Pb(II) cations for active sites on the surface of AN and Q-AN. Besides, the surface of AN and Q-AN turned into a negative charge when pH increased [33–35]. And it was confirmed by estimating the Zeta potential of AN and Q-AN at pH 2–7. Figure 4b indicates an obvious decrease of Zeta potential from −1.41 to −32.94 mV (AN) and −1.99 to −44.70 mV (Q-AN) when pH enhanced from 2 to 7. Namely, the more negative the nanoparticles are charged, the stronger is the electrostatic attraction between them and Pb(II). Therefore, an increasing acidic medium facilitated Pb(II) adsorption by affecting both the lead species and adsorbent surface.Fig. 4

Bottom Line: Characterization of AN and Q-AN were analysed by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffractometer (XRD), and thermogravimetric analysis (TG-DTG-DSC).AN and Q-AN, with a diameter of 95.06 and 58.23 nm, were constituted by many small primary nanoparticles.AN and Q-AN would probably be applied as adsorbents to remove Pb(II) and then recover it from wastewater for the advantages of simple preparation, high adsorption capacity, and recyclability.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Environmental Science and Engineering, Tianjin University, No. 92, Weijin Rd., Nankai District, Tianjin, 300072, China. qiyun@tju.edu.cn.

ABSTRACT
Pb(II) is a representative heavy metal in industrial wastewater, which may frequently cause serious hazard to living organisms. In this study, comparative studies between alginate nanoparticles (AN) and quercetin-decorated alginate nanoparticles (Q-AN) were investigated for Pb(II) ion adsorption. Characterization of AN and Q-AN were analysed by transmission electron microscopy (TEM), Fourier transform infrared spectrometry (FT-IR), X-ray diffractometer (XRD), and thermogravimetric analysis (TG-DTG-DSC). The main operating conditions such as pH, initial concentration of Pb(II), and co-existing metal ions were also investigated using a batch experiment. AN and Q-AN, with a diameter of 95.06 and 58.23 nm, were constituted by many small primary nanoparticles. It revealed that when initial concentration of Pb(II) is between 250 and 1250 mg L(-1), the adsorption rate and equilibrium adsorption were increased with the increase of pH from 2 to 7. The maximum adsorption capacities of 147.02 and 140.37 mg L(-1) were achieved by AN and Q-AN, respectively, with 0.2 g adsorbents in 1000 mg L(-1) Pb(II) at pH 7. The adsorption rate of Pb(II) was little influenced by the co-existing metal ions, such as Mn(II), Co(II), and Cd(II). Desorption experiments showed that Q-AN possessed a higher desorption rate than AN, which were 90.07 and 83.26 %, respectively. AN and Q-AN would probably be applied as adsorbents to remove Pb(II) and then recover it from wastewater for the advantages of simple preparation, high adsorption capacity, and recyclability.

No MeSH data available.


Related in: MedlinePlus