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Equilibrium, Kinetics and Thermodynamic Studies on the Removal of Safranin-O from Waste Water Using Activated Carbons Derived from Coconut Shell and Pineapple Peel
Jibrin Mohammed,
Ufaruna Idrisu Noah,
Isah Jibrin,
Kabiru Suleiman Madaki,
Stephen Ingedu Audu
Issue:
Volume 8, Issue 1, March 2019
Pages:
1-10
Received:
14 December 2018
Accepted:
9 January 2019
Published:
30 January 2019
Abstract: This work is aimed at comparing the adsorption capacities of the activated carbons derived from coconut shell and pineapple peels using Safranin-O as adsorbate. Physical activation method was employed to generate the activated carbons using phosphoric acid (H3 PO4) as activating agent. Batch adsorption experiment was employed for the adsorption process. Effects of experimental factors such as adsorbent dosage, inititial Safranin-O dye concentration, pH and contact time on the adsorption process were examined. The results showed that the adsorption capacities were dependent on these factors. Langmuir and Freundlich Isotherms Models were applied and the results indicated that both models fitted well with the observed data but Freundlich Model fitted better. Pseudo first and second order kinetic models were also applied to describe the adsorption kinetic, only the second order model fitted well with the experimental data. Thermodynamic parameters such as enthalpy change (∆H), Gibb’s free energy change (∆G) and entropy change (∆S) were evaluated using Van’t Hoff equations, both the free energy and enthalpy change were found to be negative indicating the feasibility and exorthermic nature of the adsorption process respectively. While the entropy change was found to be positive indicating that the degree of dispersion in the adsorption process increased with increase in temperature, Based on the results obtained from this research work, the activated carbon derived from coconut shell (CSAC) showed better adsorbent when compared with the one derived from pineapple peel (PPAC) as CSAC recorded the highest percentage of Safranin-O dye removal from waste water under all the experimental conditions.
Abstract: This work is aimed at comparing the adsorption capacities of the activated carbons derived from coconut shell and pineapple peels using Safranin-O as adsorbate. Physical activation method was employed to generate the activated carbons using phosphoric acid (H3 PO4) as activating agent. Batch adsorption experiment was employed for the adsorption pro...
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Determination of the Corrosion Inhibition Effect of Terminalia Ivorensis Leaves Extract on Galvanized and Mild Steel in Sulphuric Acid Media
Maduelosi Ngozi Jane,
Timothy Micheal Nakara
Issue:
Volume 8, Issue 1, March 2019
Pages:
11-16
Received:
31 October 2018
Accepted:
20 December 2018
Published:
27 March 2019
Abstract: The susceptibility of metals to corrosion due to attack by their environment has necessitated the search for corrosion inhibitors which can protect the metals and also be friendly with the environment. In this research, corrosion inhibition study of Terminalia ivorensis leaves extract on galvanized and mild steel in 1.0M Sulphuric acid was carried out to determine the corrosion inhibition ability of the leaves extract on the metals using weight loss method in three different concentrations (15g/l, 10g/l and 5g/l) of the extract and the acid solution. The metals were immersed in the solution for a period 432hours. The weight loss of the metals was checked at 72hours intervals. The results obtained reveal that there was decrease in weight loss of the metals immersed in the solution with the extract which indicates that the extract is a good corrosion inhibitor for galvanized and mild steel in sulphuric acid. The inhibition efficiency increased with increase in extract concentration at the temperature of study (ambient temperature). Maximum inhibition efficiency of 92.47% on mild steel and 82.10% on galvanized steel were obtained at the optimum concentration of the extract (15.0g/l). The inhibitive action was attributed to the presence of some notable phytochemical components of the leaves which possessed lone pairs of electrons that gave oxidative protection to the metals. It was observed that the protection by the extract was as a result of the adsorption of the extract on the metals and the experimental data obtained revealed that the adsorption followed Langmuir adsorption isotherm.
Abstract: The susceptibility of metals to corrosion due to attack by their environment has necessitated the search for corrosion inhibitors which can protect the metals and also be friendly with the environment. In this research, corrosion inhibition study of Terminalia ivorensis leaves extract on galvanized and mild steel in 1.0M Sulphuric acid was carried ...
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Number of Classes of Invariant Equilibrium States in Complex Thermodynamic Systems
Issue:
Volume 8, Issue 1, March 2019
Pages:
17-25
Received:
5 April 2019
Accepted:
14 May 2019
Published:
11 June 2019
Abstract: The values of the Gibbs function of a system with C components create a 2‑dimensional topological manifold that is piecewise smooth and continuous. Each of the C+2 smooth elements of such a manifold represents the states of a phase within the system. The elements are glued together along the C types of phase transformation lines, which converge to a single point that represents the invariant state of the system (i.e. a state with zero degrees of freedom). Transformation lines, treated as edges, and the smooth elements of the manifold, i.e. faces, constitute a zero-vertex graph that represents the invariant state. This graph is referred to here as the graph-map of the invariant state. The distribution of each component in an invariant state depends on the configuration (distribution) of the phase transformation lines. Because the smoothness and continuity of the manifold makes certain configurations of the lines forbidden, some forms of invariant states are also forbidden, even though they satisfy the Gibbs phase rule. Some academic handbooks do not take this fact into account, and provide forbidden configurations as examples of invariant states. States that only differ in terms of the permutation of two or more of their components will belong to the same class. This study shows that all real graph-maps can be represented by C-vertex graphs with C+2 edges that have an even value of the vertex valence. The number of such graphs, i.e. the number of classes of invariant states, ho(C), is shown to meet the recurrence relation ho(2k+1) = 2*ho(2k) - ho(2k-1), where k = 1, 2, 3, 4. Knowing the number ho(C) for several small values of C allows us to determine the number of invariant states in a thermodynamic system using the above equation, regardless of the complexity of the system.
Abstract: The values of the Gibbs function of a system with C components create a 2‑dimensional topological manifold that is piecewise smooth and continuous. Each of the C+2 smooth elements of such a manifold represents the states of a phase within the system. The elements are glued together along the C types of phase transformation lines, which converge to ...
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Possibility of Predicting Activation Energy for Viscous Flow in Five-Membered Naphthenes by Means of Structural Descriptors
Ella Kovaleva,
Mikhail Dolomatov,
Кamil Latypov,
Oleg Koledin,
Nataliya Paymurzina
Issue:
Volume 8, Issue 1, March 2019
Pages:
26-31
Received:
26 February 2019
Accepted:
29 April 2019
Published:
13 June 2019
Abstract: In this paper, the possibility of predicting values apparent activation energy for viscous flow in five-membered naphthenes by the calculation method, namely, using the two-parameter dependence of structural descriptors, is investigated. We explore structural descriptors of the molecular graph, namely, a topological index and the sum of eigenvalues squares of the topological matrix. Interchangeability checking of topological descriptors was performed. We performed regression analysis, and constructed dependences of apparent activation energy on the sum of squares of eigenvalues and topological indices. This paper presents data for calculating apparent activation energy of viscous flow from the experimental data and from the dependence on the Wiener topological index and the squares sum of eigenvalues. It is shown that for compounds under consideration there is a kinetic compensation effect. Based on the studies carried out for compounds considered, it can be assumed that, the apparent activation energy of viscous flow and the associated Arrhenius constant (frequency factor) is determined by the topological characteristics of the molecules.
Abstract: In this paper, the possibility of predicting values apparent activation energy for viscous flow in five-membered naphthenes by the calculation method, namely, using the two-parameter dependence of structural descriptors, is investigated. We explore structural descriptors of the molecular graph, namely, a topological index and the sum of eigenvalues...
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