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Kinetics and Thermodynamics of Some Heavy Metals Removal from Industrial Effluents Through Electro-Flotation Process
K. A. Selim,
F. I. El Hosiny,
M. A. Abdel Khalek,
I. Osama
Issue:
Volume 2, Issue 2, June 2017
Pages:
47-53
Received:
31 December 2016
Accepted:
18 January 2017
Published:
15 February 2017
DOI:
10.11648/j.css.20170202.11
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Abstract: The electrokinetic of chromium, copper, silver and gold ions removal from synthetic and wastewater via electro-flotation was investigated. Kinetics and thermodynamic parameters of the electro-flotation process were determined. The effect of initial pH and metal ion concentration, treatment time and temperature showed that the maximum removal was achieved at pH 6. The order of the metal ions removal is Cr3+ > Cu2+> Ag+ > Au+. The removal process follows pseudo first-order kinetics and the adsorption is a heterogeneous system characterized by physical adsorption which is exothermic. Negative values of entropy change ΔS° and Gibbs free energy change ΔG° indicate that this adsorption process is spontaneous and less favorable at high temperatures. The treatment of electroplating wastewater showed that the removal efficiency was ranging between 96 - 99%. The electrical energy consumption was 0.033 Kwh/L.
Abstract: The electrokinetic of chromium, copper, silver and gold ions removal from synthetic and wastewater via electro-flotation was investigated. Kinetics and thermodynamic parameters of the electro-flotation process were determined. The effect of initial pH and metal ion concentration, treatment time and temperature showed that the maximum removal was ac...
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Carbon Dioxide Photocatalytic Hydrogenation by Water on Well-Defined Non-stoichiometric Molybdenum Oxide Surface
Galina S. Grigorkina,
Aljona G. Ramonova,
David D. Kibizov,
Vladislav B. Zaalishvili,
Ol’ga. G. Burdzieva,
Oleg G. Ashkhotov,
Markus Wilde,
Shohei Ogura,
Katzuyuki Fukutani,
Tamerlan T. Magkoev
Issue:
Volume 2, Issue 2, June 2017
Pages:
54-58
Received:
24 December 2016
Accepted:
7 February 2017
Published:
27 February 2017
DOI:
10.11648/j.css.20170202.12
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Abstract: Reaction between carbon dioxide and water on molybdenum oxide surface, induced by ultraviolet photons, has been studied in ultra-high vacuum by a set of surface sensitive techniques. On oxygen deficient Molybdenum oxide (IV), carbon dioxide quite efficiently hydrogenates via sequential conversion steps: formic acid – formaldehyde – methoxide – methanol. Molybdenum oxide should be only partly nonstoichiometric, while a certain part of the substrate surface should retain the MoO2 stoichiometry to accommodate reaction intermediates.
Abstract: Reaction between carbon dioxide and water on molybdenum oxide surface, induced by ultraviolet photons, has been studied in ultra-high vacuum by a set of surface sensitive techniques. On oxygen deficient Molybdenum oxide (IV), carbon dioxide quite efficiently hydrogenates via sequential conversion steps: formic acid – formaldehyde – methoxide – meth...
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State-of-Art on Hybridization of Natural Fiber Reinforced Polymer Composites
G. R. Arpitha,
M. R. Sanjay,
B. Yogesha
Issue:
Volume 2, Issue 2, June 2017
Pages:
59-65
Received:
21 January 2017
Accepted:
8 February 2017
Published:
1 March 2017
DOI:
10.11648/j.css.20170202.13
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Abstract: New improvements are going on to investigate the new thoughts of various applications of composites. Composites produced using natural and synthetic fibers are utilized for numerous applications such as aviation, marine, sports, furniture and different applications. There are studies in progress to durable furniture and new geometrical auxiliary structures and additionally bikes, tricycles and auto bodies. In this the key trust zones are taking after for composite materials are short and long haul innovative work, creation and testing bolster, accessibility and evaluating of crude materials, labor preparing, specialized bolster administrations for materials and procedure determination, process streamlining and outline, product quality improvement. Keeping in this view a thorough review on the manufacturing techniques, material properties and progressive of natural fiber composite materials are studied in this paper.
Abstract: New improvements are going on to investigate the new thoughts of various applications of composites. Composites produced using natural and synthetic fibers are utilized for numerous applications such as aviation, marine, sports, furniture and different applications. There are studies in progress to durable furniture and new geometrical auxiliary st...
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Preparation and Characterization of Polymeric Nanofibers by Electrospinning as Potential Antibacterial Materials
Yasser Assem,
A. I. Khalaf
Issue:
Volume 2, Issue 2, June 2017
Pages:
66-75
Received:
31 January 2017
Accepted:
20 February 2017
Published:
3 March 2017
DOI:
10.11648/j.css.20170202.14
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Abstract: Quaternized PDMAEMA (qPDMAEMA) was used to prepare nanofibers by electrospinning. At first the DMAEMA monomer was quaternized using Hexyl, dodecyl and hexadecyl bromide. Then the quaternized DMAEMA was polymerized by free radical polymerization. This polymer was characterized by 1HNMR, GPC, and thermal analysis (DSC and TGA). The (qPDMAEMA) was blended with PVA in different ratios (20/80, 25/75 and 50/50). The antibacterial properties of the prepared blends were examined against two strains type, the gram positive M. luteus and the gram negative E.coli. The antimicrobial activity showed that all blends with different alkyl side chain length (i.e. 6, 12, and 16) are highly active against M. luteus and no growth of the bacteria was observed after incubation period of 96 h, but in case of E. coli, the antibacterial activity is different. The blend having short alkyl side chain (6) are very active and can kill all the bacteria colonies. Blends that contain longer side chains are mostly inactive. However the blend compositions of PVA/PDMAEMA-12 (80/20 and 75/25) exhibit a good antimicrobial effect against E. Coli. The minimum bactericidal concentration (MBC) was obtained by determining the minimum polymer concentration at which no growth was observed. qPDMAEMA based fibers were produced using a solution blend of PDMAEMA and PVA. The quaternized PDEAMMAs/PVA blends were electrospun in ethanol. The concentration of the polymer was as high as 20% in order to get fibers. The diameter of formed fibers was found to be around 500 nm.
Abstract: Quaternized PDMAEMA (qPDMAEMA) was used to prepare nanofibers by electrospinning. At first the DMAEMA monomer was quaternized using Hexyl, dodecyl and hexadecyl bromide. Then the quaternized DMAEMA was polymerized by free radical polymerization. This polymer was characterized by 1HNMR, GPC, and thermal analysis (DSC and TGA). The (qPDMAEMA) was ble...
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Microstructural and High Tc Dielectric Properties of Microwave Sintered Ba0.7Ca0.3TiO3 (BCT) Ceramic
Sagar M. Mane,
Pravin M. Tirmali,
Snehal L. Kadam,
Chandrakant B. Kolekar,
Shrinivas B. Kulkarni
Issue:
Volume 2, Issue 2, June 2017
Pages:
76-80
Received:
13 January 2017
Accepted:
11 March 2017
Published:
10 April 2017
DOI:
10.11648/j.css.20170202.15
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Abstract: Nanopowder of Ba0.7Ca0.3TiO3 (BCT) lead free ferroelectric ceramic was synthesized by hydroxide co-precipitation method. As-synthesized powder is sintered using the microwave sintering technique at different temperature 1100°C and 1200°C. Sintered ceramic samples were investigated for its structural, morphological, and temperature dependent dielectric properties. Structural analysis confirms biphasic crystal structure, tetragonal phase corresponding to BaTiO3 lattice and orthorhombic phase resulting from the CaTiO3 lattice. Scanning electron microscope images reveals the formation of grains with higher density. Ferroelectric-Paraelectric transition (Tc) of the material shifts towards higher temperature (Tc ~ 155°C) with maximum dielectric constant and low loss tangent.
Abstract: Nanopowder of Ba0.7Ca0.3TiO3 (BCT) lead free ferroelectric ceramic was synthesized by hydroxide co-precipitation method. As-synthesized powder is sintered using the microwave sintering technique at different temperature 1100°C and 1200°C. Sintered ceramic samples were investigated for its structural, morphological, and temperature dependent dielect...
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