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Efficiency of Rice Husk for Removal of Cu(II) and Zn(II) Ions from Aqueous Solution
Belete Geremew,
Tesfahun Kebede
Issue:
Volume 5, Issue 5, September 2017
Pages:
66-71
Received:
23 June 2016
Accepted:
4 July 2016
Published:
11 October 2017
Abstract: In the present study the adsorption of Cu(II) and Zn(II) ions on rice husk from artificially prepared aqueous solutions of these metal ions was investigated following the batch mode adsorption procedure. Accordingly, the effects of operating parameters such as pH, contact time, and initial concentration of metal ion solution were evaluated. The results so obtained in this study indicated that the optimum conditions for the Cu(II) and Zn(II) ions adsorption were found to be as follows: pH of 6 and 7; contact times of 100 and 125 minutes; and these values were actually determined by setting the initial concentration of 50mg/L for each metal ion solution. Upon measurements of the residual metal ion concentration using FAAS method, the percent adsorption of both Cu(II) and Zn(II) ions showed significant increase with an increase in each case of the contact time. Furthermore, it was evidently implicated that the binding process of the metal ions on the adsorbent (rice husk) could be affected by change in the pH of both metal ion solutions. In addition the experimental data were analyzed against both Langmuir and Freundlich isotherm for determining the maximum adsorption capacity of the title biosorbent with respect to each of the tested metal ions. The adsorption maxima were calculated on the basis the Langmuir isotherm and found to be 1.93 and 12.98 mg/g for Cu(II) and Zn(II) metal ions respectively. These values were suggested that the rice husk investigated in this study can have a good application potential for the removal of both metal ions (Cu(II) and Zn(II)) from aqueous solutions. In fact, the goal of this work was to develop an inexpensive, highly available, effective metal ion adsorbent from natural waste as alternative to existing commercial adsorbents.
Abstract: In the present study the adsorption of Cu(II) and Zn(II) ions on rice husk from artificially prepared aqueous solutions of these metal ions was investigated following the batch mode adsorption procedure. Accordingly, the effects of operating parameters such as pH, contact time, and initial concentration of metal ion solution were evaluated. The res...
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A Review on Elimination of Heavy Metals from Wastewater Using Agricultural Wastes as Adsorbents
Issue:
Volume 5, Issue 5, September 2017
Pages:
72-75
Received:
29 June 2016
Accepted:
16 July 2016
Published:
13 October 2017
Abstract: In this article, the potential of various low-cost adsorbents for the removal of heavy metals from contaminated water has been reviewed. There are various conventional methods for heavy metal removal from wastewater such as precipitation, evaporation, electroplating and also ion-exchange have been applied since previous years. However, these methods have several disadvantages such as only limited to certain concentrations of metals ions, generation large amount of toxic sludge and the capital costs are much too high to be economical. Adsorption is the alternative process for heavy metal removal due to the wide number of natural materials or agricultural wastes gathering in abundance from our environment. In this review, a list of adsorbent has been compiled to provide available information on a wide range of low cost adsorbents for removing heavy metals from wastewater.
Abstract: In this article, the potential of various low-cost adsorbents for the removal of heavy metals from contaminated water has been reviewed. There are various conventional methods for heavy metal removal from wastewater such as precipitation, evaporation, electroplating and also ion-exchange have been applied since previous years. However, these method...
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Calculations Using Quantum Chemistry for Inorganic Molecule Simulation BeLi2SeSi
Ricardo Gobato,
Alireza Heidari
Issue:
Volume 5, Issue 5, September 2017
Pages:
76-85
Received:
20 June 2017
Accepted:
17 July 2017
Published:
18 October 2017
Abstract: Inorganic crystals have been used in the most diverse electronic systems since the nineteenth century, which apply to the wide variety of technological applications, which are the quartz crystals are the most used. Elements such as beryllium, lithium, silicon and selenium are widely used. The difficulty of finding such crystals from the combination of elements in nature or synthesized, suggest an advanced study of the same. In this sense, these elements were chosen because of the physical-chemical properties of each one, to simulate a seed molecule whose arrangement would be formed by the combination of these, aiming at the future development of a crystal to be used technologically. A study using computer programs with ab initio method was applied and the quantum chemistry was utilized through Molecular Mechanics, Hartree-Fock, Møller-Plesset and Density Functional Theory, on several bases. The main focus was to obtain a stable molecular structure acceptable to quantum chemistry. As a result of the likely molecular structure of the arrangement of a crystal was obtained, beyond the dipole moment, thermal energy, heat of vaporization and entropy of the molecule. The simulated molecule has a cationic molecular structure, in the atoms Selenium and Silicon. As a consequence, it has a strong electric dipole moment. Due to its geometry, it presents a probable formation structure of a crystal with a tetrahedral and hexahedral crystal structure.
Abstract: Inorganic crystals have been used in the most diverse electronic systems since the nineteenth century, which apply to the wide variety of technological applications, which are the quartz crystals are the most used. Elements such as beryllium, lithium, silicon and selenium are widely used. The difficulty of finding such crystals from the combination...
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On S Degrees of Vertices and S Indices of Graphs
Issue:
Volume 5, Issue 5, September 2017
Pages:
86-89
Received:
9 June 2017
Accepted:
17 July 2017
Published:
18 October 2017
Abstract: Topological indices have been used to modeling biological and chemical properties of molecules in quantitive structure property relationship studies and quantitive structure activity studies. All the degree based topological indices have been defined via classical degree concept. In this paper we define a novel degree concept for a vertex of a simple connected graph: S degree. And also we define S indices of a simple connected graph by using the S degree concept. The S indices for well-known simple connected graphs such as paths, stars, complete graphs and cycles were calculated.
Abstract: Topological indices have been used to modeling biological and chemical properties of molecules in quantitive structure property relationship studies and quantitive structure activity studies. All the degree based topological indices have been defined via classical degree concept. In this paper we define a novel degree concept for a vertex of a simp...
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