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Pine Wood Powder Treatment to BXH+ Homogeneous Catalyst (H+/H2SO4) Supported on Its Aromatics’ and PNA’ Alkenes – Application in Black Citric Acid Polymer Synthesis
Andry Tahina Rabeharitsara,
Behevitra Rovatahianjanahary,
Nambinina Richard Randriana
Issue:
Volume 4, Issue 1, March 2018
Pages:
1-27
Received:
9 March 2018
Accepted:
27 March 2018
Published:
4 May 2018
Abstract: For a long time, many chemical reactions drew on catalysts, products used in smallest quantities compared to products-reagents, to accelerate their kinetics. In certain cases, one of the determining factors to improve these catalysts activities is the use of supports allowing dispersions and thereafter the effectiveness of its active sites.. It is the goal of our study, to increase the pine wood powders value like support of active acid H+ sites of sulphuric acid molecules by hydrogen bond connection with alkenes of aromatics and polynuclear aromatics which were pine wood components and their derivatives obtained after sulphuric acid solution (98%) treatment. Among these derivatives we quote water molecules formed during dehydration and esterification of wood components. Thus, we obtained homogeneous catalysts BXH+, (H+/H2SO4) supported on pine wood powder which we tested by a test reaction: citric acid dehydration to prop-1-ene 1, 2, 3 acid- tricarboxylic acid. Also, the active acid sites (H+/H2SO4) contents and alkenes on BXH+ catalysts were quantified by measuring out respectively with NaOH 0.05N and hydrofluoric acid (HF). This last measuring out enabled us to evaluate the nature of the aromatics and polynuclear aromatics which were the real supports contained in pine wood. At the end, we used these BXH+ synthesized catalysts to catalyze the citric acid black polymer synthesis (PN). The soluble coke and insoluble coke in polar solvent dichloromethane and non-polar solvent hexane of citric acid black polymer synthesized by each catalyst were quantified.
Abstract: For a long time, many chemical reactions drew on catalysts, products used in smallest quantities compared to products-reagents, to accelerate their kinetics. In certain cases, one of the determining factors to improve these catalysts activities is the use of supports allowing dispersions and thereafter the effectiveness of its active sites.. It is ...
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Effect of Elevated Temperature on Mechanical Properties of Waste Polymers Polyethylene Terephthalate and Low Density Polyethylene Filled Normal Concrete Blocks
Kevin Ibe Ejiogu,
Paul Andrew Mamza,
Peter Obinna Nkeonye,
Shehu Aliyu Yaro
Issue:
Volume 4, Issue 1, March 2018
Pages:
28-35
Received:
22 April 2018
Accepted:
7 May 2018
Published:
2 June 2018
Abstract: Thermal properties of M30 normal concrete block (NC) were compared with concrete filled with waste poly ethylene terephthalate and waste low density polyethylene aggregates which were used as partial replacement of sand in the production of concrete blocks (plast-cretes). Tests were carried out using 100mm×100mm Cubes and 100mm×200mm Cylinder for Compressive and Split tensile Test respectively. The mechanical properties of normal concrete and plast-crete were studied and compared over two temperature regimes at 100°C-400°C and 400°C-800°C. The compressive and Split Tensile strength of normal concrete increased slightly from 100°C-400°C, and reduced from 400°C-800°C. However, the compressive and split tensile strength of the plast-crete showed a gradual reduction from 100°C-400°C and this continued from 400°C-800°C, and became more pronounced as the percentage of waste plastics in the plast-crete increased. The percentage of weight loss for the normal concrete increased from 100°C-400°C, this increase continued from 400°C-800°C. The plast-crete also showed an increase in the percentage weight loss for both temperature regimes and the percent weight loss became more pronounced as the percentage of waste plastics in the plast-crete increased. The normal concrete showed greater spalling than the plat-cretes. Even with the slight reduction in strength with increasing temperature, Plast-cretes can still be applied in areas where low temperature and minimal load bearing applications are needed such as fancy blocks, pedestrian walk ways, slabs, partition walls, fences, houses and light traffic structures.
Abstract: Thermal properties of M30 normal concrete block (NC) were compared with concrete filled with waste poly ethylene terephthalate and waste low density polyethylene aggregates which were used as partial replacement of sand in the production of concrete blocks (plast-cretes). Tests were carried out using 100mm×100mm Cubes and 100mm×200mm Cylinder for C...
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Adhesives and Adhesion Technologies: A Critical Review
Issue:
Volume 4, Issue 1, March 2018
Pages:
36-41
Received:
29 July 2018
Accepted:
30 August 2018
Published:
17 September 2018
Abstract: The article critically reviews about adhesives and their various adhesion phenomenons along with their categorization and functions. Benefit and drawbacks of adhesives joining was explained. Requirements for excellent bonding which includes, appropriate selection of adhesive, superior design for joining, surface cleansing, wetting were defined. The review clearly indicates the various theories involved in adhesion are namely mechanical interlocking, electrostatic, diffusion, wetting, chemical bonding, and weak boundary layer. Bond failure modes and their mechanism were elaborated briefly.
Abstract: The article critically reviews about adhesives and their various adhesion phenomenons along with their categorization and functions. Benefit and drawbacks of adhesives joining was explained. Requirements for excellent bonding which includes, appropriate selection of adhesive, superior design for joining, surface cleansing, wetting were defined. The...
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