Elucidation of Interactions between Metal Ions and Ca Alginate-Based Ion-Exchange Resin by Spectroscopic Analysis and Modeling Simulation

Chen, Jiaping; Hong, Liang; Wu, and Shunnian; Wang, Lin

doi:10.1021/la026060v

Cited by 226 publications

(144 citation statements)

References 23 publications

(34 reference statements)

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“…Bands corresponding to the stretching vibration of free -C=O groups and the asymmetric stretching of -O-C-O -in NaAlg 55 were deconvoluted into three bands by curve fitting. The peak positions of the three deconvoluted bands were 1739, 1645, and 1601 cm -1 ( Figure 7B).…”

Section: One-dimensional Ft-ir Analysismentioning

confidence: 99%

Study on antibacterial alginate-stabilized copper nanoparticles by FT-IR and 2D-IR correlation spectroscopy

Díaz-Visurraga¹,

Daza²,

Pozo³

et al. 2012

IJN

102

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Background:The objective of this study was to clarify the intermolecular interaction between antibacterial copper nanoparticles (Cu NPs) and sodium alginate (NaAlg) by Fourier transform infrared spectroscopy (FT-IR) and to process the spectra applying two-dimensional infrared (2D-IR) correlation analysis. To our knowledge, the addition of NaAlg as a stabilizer of copper nanoparticles has not been previously reported. It is expected that the obtained results will provide valuable additional information on: (1) the influence of reducing agent ratio on the formation of copper nanoparticles in order to design functional nanomaterials with increased antibacterial activity, and (2) structural changes related to the incorporation of Cu NPs into the polymer matrix. Methods: Cu NPs were prepared by microwave heating using ascorbic acid as reducing agent and NaAlg as stabilizing agent. The characterization of synthesized Cu NPs by ultraviolet visible spectroscopy, transmission electron microscopy (TEM), electron diffraction analysis, X-ray diffraction (XRD), and semiquantitative analysis of the weight percentage composition indicated that the average particle sizes of Cu NPs are about 3-10 nm, they are spherical in shape, and consist of zerovalent Cu and Cu 2 O. Also, crystallite size and relative particle size of stabilized Cu NPs were calculated by XRD using Scherrer's formula and FT from the X-ray diffraction data. Thermogravimetric analysis, differential thermal analysis, differential scanning calorimetry (DSC), FT-IR, second-derivative spectra, and 2D-IR correlation analysis were applied to studying the stabilization mechanism of Cu NPs by NaAlg molecules. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of stabilized Cu NPs against five bacterial strains (Staphylococccus aureus ATCC 6538P, Escherichia coli ATCC 25922 and O157: H7, and Salmonella enterica serovar Typhimurium ATCC 13311 and 14028) were evaluated with macrodilution, agar dilution plate count, and well-diffusion methods. Results: On the basis of the semiquantitative analysis, there was a direct correlation between the reducing agent ratio and the percentage of zerovalent Cu. This was confirmed with the statistical analysis of population of Cu NPs from TEM micrographs. At lower reducing agent ratios, two phases coexist (Cu 2 O and zerovalent Cu) due to incomplete reduction of copper ions by the reducing agent; however, at higher reducing agent ratios, the Cu NPs consist mainly of zerovalent Cu. Crystallite size and relative particle size of stabilized Cu NPs showed considerable differences in results and tendencies in respect to TEM analysis. However, the relative particle size values obtained from FT of XRD data agreed well with the histograms from the TEM observations. From FT results, the relative particle size and reducing agent ratio of stabilized Cu NPs showed an inverse correlation. The incomplete reduction of copper ions at lower reducing agent ratios was also confirmed by DSC studies. FT-IR and 2D-IR correl...

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Section: One-dimensional Ft-ir Analysismentioning

confidence: 99%

Study on antibacterial alginate-stabilized copper nanoparticles by FT-IR and 2D-IR correlation spectroscopy

Díaz-Visurraga¹,

Daza²,

Pozo³

et al. 2012

IJN

102

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“…Tech., 37 (19), 4449-4456 (8 pages). Chen, J. P.; Hong, L.; Wu, S. N.;Wang, L., (2002) A.; Rollemberg, M. C., (2005). Equilubrium studies for the sorption of crmium and nickel from aqueous solutions using raw rice bran.…”

Section: Acknowledgementsmentioning

confidence: 99%

“…Earlier studies on heavy metal biosorption have shown that solution pH is the single most important parameter affecting the biosorption process (Chen et al, 2002). In order to establish the effect of pH on the biosorption of chromium (VI) ions, batch sorption studies at different pH values were conducted in the range of 2.0 to 8.0.…”

Section: Effect Of Ph On Sorptionmentioning

confidence: 99%

Relevant approach to assess the performance of sawdust as adsorbent of chromium (VI) ions from aqueous solutions

Vinodhini

Das

2009

Int. J. Environ. Sci. Technol.

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ABSTRACT:The biosorption of chromium (VI) ions from aqueous solutions by two adsorbents viz. mango and neem sawdust was studied under a batch mode. An initial pH of 2.0 was most favorable for chromium (VI) removal by both the adsorbents. The results obtained for the final concentration of chromium (VI) and chromium (III) at a pH range of 2-8 indicated that a combined effect of biosorption and reduction was involved in the chromium (VI) removal specially when the pH value is lower than 3. The maximum loading capacity was calculated from adsorption isotherms by applying the Langmuir model and found to be higher for neem sawdust (58.82 mg/g). Evaluation of experimental data in terms of biosorption kinetics showed that the biosorption of chromium (VI) by neem sawdust followed pseudo second-order kinetics. Therefore, the rate limiting step may be chemical sorption or chemisorption. The efficiency of this process was examined in using tannery wastewater contaminated with chromium (VI) ions in column mode. ). The raw tannery wastewater sample collected from a common effluent treatment plant (CETP) located in Vaniyambadi, Vellore Dt., Tamil Nadu, India was analyzed promptly for determining the physicochemical characteristics using standard analytical methods (APHA, 1998). The characteristics of the wastewater were: color: black, pH: 6.1, TDS: 7794 mg/L, TSS: 4896 mg/L, sulphates: 878 mg/L, chlorides: 2927 mg/L and nitrate: 9.8 mg/L. The concentration of chromium (VI) in wastewater was detected using UV spectrophotometer: 94 mg/L and pH was adjusted to 2.0 using 0.1 N HNO 3 . The wastewater was then fed through a glass column (3 cm i.d. and 10cm long) packed with 20 g of the biosorbent neem sawdust at a flow rate of 5.0 mL/min controlled by a peristaltic pump. After treatment, the samples collected from the exit were analyzed for chromium (VI) concentrations. The wastewater was treated till the values reached to satisfy the Central Pollution Control Board (CPCB) standards (Cr (VI) -0.1 mg/L) (CPCB, 1998). Keywords RESULTS AND DISCUSSION Effect of pH on sorptionEarlier studies on heavy metal biosorption have shown that solution pH is the single most important parameter affecting the biosorption process (Chen et al., 2002). In order to establish the effect of pH on the biosorption of chromium (VI) ions, batch sorption studies at different pH values were conducted in the range of 2.0 to 8.0. Fig. 1 reveals that biosorption capacity of Cr (VI) ions is maximum at pH 2.0 and significantly decreases with increase in pH values upto 8.0. At pH 2 and 8 corresponding uptake yield values were found to be 80.1% and 7.6 % for neem sawdust, 60 % and 6.3 % for mango sawdust, respectively.At lower pH, the biosorbent is positively charged due to protonation and dichromate ion exists as anion leading to an electrostatic attraction between them (Boddu et al., 2003). Thus the uptake of chromium (VI) increased markedly with decreasing pH. A sharp decrease in adsorption above pH 4 may be due to occupation of the adsorption sites by anionic spe...

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“…This observation is in good agreement with the known higher affinity of Pb 2+ for the AA carboxyl groups and is consistent with the existing literature on alginatecontaining biomasses. 6,8,12,44 It is difficult to compare the above stability constants with literature results, given that the experiments were not performed using the same alginates, nor in the same intervals of pH, ionic strength, or metal-to-ligand ratios. In particular, the metal binding properties of the AA are very dependent on its guluronic acid content.…”

Section: Effects Of the Ionic Strengthmentioning

confidence: 99%

“…For example, in algae, alginates have a structural function, whereas in bacteria, they generally adopt a more acetylated form that serves a protective function. 5 Because of their metal binding properties, alginates can be used to remove metals from wastewaters and industrial effluents 2,6 and as a matrix to immobilize Pb and Cd complexing particles, including ion-exchange resins 6 or microorganisms 7 in order to treat contaminated waters. The major difficulties in understanding the metal binding of most natural biopolymers, including alginates, results from their (i) polyelectrolytic properties -at circumneutral pH, the carboxylic sites of alginic acid are ionized, thereby creating an electric field which increases complex stability; (ii) polyfunctionality -a diversity in the chemical nature and the resulting electronic and steric environment of the coordinating sites; and (iii) capacity to change their threedimensional conformation.…”

Section: Introductionmentioning

confidence: 99%

Quantifying Pb and Cd Complexation by Alginates and the Role of Metal Binding on Macromolecular Aggregation

et al. 2005

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The Pb and Cd binding capacity of alginates were quantified by the determination of their complex stability constants and the concentration of complexing sites using H + , Pb 2+ , or Cd 2+ selective electrodes in both static and dynamic titrations. Centrifugation filter devices (30 kDa filter cutoff), followed by inductively coupled plasma mass spectrometry (ICP-MS) measurements of lead or cadmium in the filtrates, were used to validate the results. The influence of ionic strength, pH, and the metal-to-alginate ratio was determined for a wide range of metal concentrations. Because of their polyelectrolytic properties, alginates may adopt different conformations depending on the physicochemistry of the medium, including the presence of metals. Therefore, molecular diffusion coefficients of the alginate were determined by fluorescence correlation spectroscopy under the same conditions of pH, ionic strength, and metal-to-alginate ratios that were used for the metal binding studies. The complexation and conformational properties of the alginate were related within the framework of the nonideal competitive adsorption isotherm (NICA) combined with a Donnan approach to account for both intrinsic and electrostatic contributions.

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Elucidation of Interactions between Metal Ions and Ca Alginate-Based Ion-Exchange Resin by Spectroscopic Analysis and Modeling Simulation

Cited by 226 publications

References 23 publications

Study on antibacterial alginate-stabilized copper nanoparticles by FT-IR and 2D-IR correlation spectroscopy

Study on antibacterial alginate-stabilized copper nanoparticles by FT-IR and 2D-IR correlation spectroscopy

Relevant approach to assess the performance of sawdust as adsorbent of chromium (VI) ions from aqueous solutions

Quantifying Pb and Cd Complexation by Alginates and the Role of Metal Binding on Macromolecular Aggregation

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