Biopolymers as Encapsulating Agents for the Immobilization of Prussian Blue and Analogues for the Sorption of Cesium

2015 ◽  
Vol 1130 ◽  
pp. 507-510 ◽  
Author(s):  
Chloë Vincent ◽  
Yves Barré ◽  
Thierry Vincent ◽  
Eric Guibal

Prussian Blue (PB, iron hexacyanoferrate) is an efficient micron-sized sorbent that can be encapsulated in a biopolymer matrix (chitin) for the treatment of Cs (I)-bearing solutions. Different conditionings have been designed for the treatment of Cs-contaminated effluents (with natural Cs (I) solutions, and with 137Cs spiked solutions). The sorbents conditioned under the form of beads or discs can be used in columns while sponges can be used for the treatment of accidental discharge of effluents (contaminated water absorption by the sponge, metal ions sorption on the ion-exchanger, treated water removal by centrifugation, metal concentration in the composite material).

2019 ◽  
Author(s):  
Chem Int

A study of removal of heavy metal ions from heavy metal contaminated water using agro-waste was carried out with Musa paradisiaca peels as test adsorbent. The study was carried by adding known quantities of lead (II) ions and cadmium (II) ions each and respectively into specific volume of water and adding specific dose of the test adsorbent into the heavy metal ion solution, and the mixture was agitated for a specific period of time and then the concentration of the metal ion remaining in the solution was determined with Perkin Elmer Atomic absorption spectrophotometer model 2380. The effect of contact time, initial adsorbate concentration, adsorbent dose, pH and temperature were considered. From the effect of contact time results equilibrium concentration was established at 60minutes. The percentage removal of these metal ions studied, were all above 90%. Adsorption and percentage removal of Pb2+ and Cd2+ from their aqueous solutions were affected by change in initial metal ion concentration, adsorbent dose pH and temperature. Adsorption isotherm studies confirmed the adsorption of the metal ions on the test adsorbent with good mathematical fits into Langmuir and Freundlich adsorption isotherms. Regression correlation (R2) values of the isotherm plots are all positive (>0.9), which suggests too, that the adsorption fitted into the isotherms considered.


2019 ◽  
pp. 1-8
Author(s):  
F. S. Nworie ◽  
S. O. Ngele ◽  
J. C. Onah

Metal ions present in waste samples, industrial effluents, acid mines and other aqueous media constitute a serious challenge in different human activities. Solvent extraction a technique for preconcentration, separation and identification of trace amount of metal ions coupled with multivariate chemometric technique was used for the determination of Fe(II) and Cr(III) from solutions in the presence of bis(salicylidene)ethylenediamine (SALEN). The influence of main extraction variables affecting the extraction efficiency was simultaneously studied and regression model equations illustrating the relationship between variables predicted. The extraction parameters (time of extraction, acid concentration, ligand concentration, temperature and metal concentration) were optimized using experimental designs with the contributions of the various parameters to extraction of the metal ions bound to the complexone evaluated using SPSS19.0 software. The statistically determined simulated models for the parameters were R2 = 0.946, 0.727, 0.793, 0.53, 0.53, 1.000 and F- values of 70.400, 13. 285, 15.348, 4.646 and 2.569×105 respectively for time of extraction, acid concentration, ligand concentration, temperature and metal concentration for Cr (III). For Fe (II), R2 = 0.243, 0.371, 0.519, 0.446, 1.000 and F-values of 0.964, 2.953, 4.310, 3.216 and 2.516×105 for time of extraction, acid concentration, ligand concentration, temperature and metal concentration respectively. The level of significance of the models as predicted was both lower than 5% making it feasible, efficient, reproducible and accurate. This means that metal ions at the conditions stated could be removed from waste samples, industrial effluents, acid mines and other aqueous media with extension in industrial scale application.


2020 ◽  
Vol 6 (11) ◽  
pp. 3080-3090
Author(s):  
Chengbo Zhan ◽  
Priyanka R. Sharma ◽  
Hongrui He ◽  
Sunil K. Sharma ◽  
Alexis McCauley-Pearl ◽  
...  

Nanocellulose scaffolds derived from rice husks could efficiently remove heavy metal ions from contaminated water.


2019 ◽  
Vol 37 (3-4) ◽  
pp. 205-216 ◽  
Author(s):  
Yujie Zhang ◽  
Quanqin Xue ◽  
Fei Li ◽  
Jizhe Dai

A polypyrrole/chitosan composite material was obtained by chemical polymerization. The adsorption performance of a hot-molded polypyrrole/chitosan composite electrode was tested by adsorption/desorption experiments. Scanning electron microscopy and Fourier-transform infrared spectroscopy both showed the deposition of polypyrrole on the chitosan surface. The specific capacitance of the polypyrrole/chitosan composite was determined by cyclic voltammetry in 1.0 M KCl at 0.01 V/s as 102.96 F/g. The adsorption/desorption experiments indicated that the specific adsorption capacity of the composite for Cu2+ was 99.67 mg/g, while the removal performance for other metal ions, such as Ag+, Pb2+, and Cd2+, was good. The results of multicycle adsorption/desorption tests showed that the adsorption rate of the polypyrrole/chitosan composite electrode for Cu2+ was decreased from 56.4 to 51.4% over 10 cycles, demonstrating the stable metal-ion adsorption/desorption behavior of the composite electrode. The obtained performances show that the prepared polypyrrole/chitosan composite material is an ideal electrode material for the removal of heavy metal ions.


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