scholarly journals Batch Sorption of Copper (II) Ions from Simulated Aqueous Solution by Banana Peel

2017 ◽  
Vol 12 (4) ◽  
pp. 117-125
Author(s):  
Lahieb Faisal M. Faisal M.
Keyword(s):  
Aqueous Solution ◽  
Free Energy ◽  
Ph Value ◽  
Entropy Change ◽  
Second Order ◽  
Free Energy Change ◽  
Energy Change ◽  
Banana Peel ◽  
Batch Sorption ◽  
Pseudo Second Order

This research presents the possibility of using banana peel (arising from agricultural production waste) as biosorbent for removal of copper from simulated aqueous solution. Batch sorption experiments were performed as a function of pH, sorbent dose, and contact time. The optimal pH value of Copper (II) removal by banana peel was 6. The amount of sorbed metal ions was calculated as 52.632 mg/g. Sorption kinetic data were tested using pseudo-first order, and pseudo-second order models. Kinetic studies showed that the sorption followed a pseudo second order reaction due to the high correlation coefficient and the agreement between the experimental and calculated values of qe. Thermodynamic parameters such as enthalpy change (ΔH°), entropy change (ΔS°) and Gibbs free energy change (ΔG°) were also investigated. Free energy change showed that biosorption of Cu (II) was spontaneous and nature endothermic at all studied temperatures (25–45 °C).

scholarly journals Kinetic and Thermodynamic Studies of Lysozyme Adsorption on Cibacron Blue F3GA Dye-Ligand Immobilized on Aminated Nanofiber Membrane

Membranes ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 963
Author(s):  
Ai Hsin ◽  
Su-Chun How ◽  
Steven S.-S. Wang ◽  
Chien Wei Ooi ◽  
Chen-Yaw Chiu ◽  
...  
Keyword(s):  
Free Energy ◽  
Free Energy Change ◽  
Energy Change ◽  
Nanofiber Membrane ◽  
Cibacron Blue ◽  
Pseudo Second Order ◽  
Nanofiber Membranes ◽  
Lysozyme Adsorption ◽  
Cibacron Blue F3ga ◽  
Pan Nanofiber

The polyacrylonitrile (PAN) nanofiber membrane was prepared by the electrospinning technique. The nitrile group on the PAN nanofiber surface was oxidized to carboxyl group by alkaline hydrolysis. The carboxylic group on the membrane surface was then converted to dye affinity membrane through reaction with ethylenediamine (EDA) and Cibacron Blue F3GA, sequentially. The adsorption characteristics of lysozyme onto the dye ligand affinity nanofiber membrane (namely P-EDA-Dye) were investigated under various conditions (e.g., adsorption pH, EDA coupling concentration, lysozyme concentration, ionic strength, and temperature). Optimum experimental parameters were determined to be pH 7.5, a coupling concentration of EDA 40 μmol/mL, and an immobilization density of dye 267.19 mg/g membrane. To understand the mechanism of adsorption and possible rate controlling steps, a pseudo first-order, a pseudo second-order, and the Elovich models were first used to describe the experimental kinetic data. Equilibrium isotherms for the adsorption of lysozyme onto P-EDA-Dye nanofiber membrane were determined experimentally in this work. Our kinetic analysis on the adsorption of lysozyme onto P-EDA-Dye nanofiber membranes revealed that the pseudo second-order rate equation was favorable. The experimental data were satisfactorily fitted by the Langmuir isotherm model, and the thermodynamic parameters including the free energy change, enthalpy change, and entropy change of adsorption were also determined accordingly. Our results indicated that the free energy change had a negative value, suggesting that the adsorption process occurred spontaneously. Moreover, after five cycles of reuse, P-EDA-Dye nanofiber membranes still showed promising efficiency of lysozyme adsorption.

Theoretical Thermodynamic Analysis and Phase Analysis of AZ91D/Flyash Composites

2014 ◽  
Vol 788 ◽  
pp. 604-607
Author(s):  
Hong Chao Chu ◽  
Si Rong Yu ◽  
Cui Xiang Wang ◽  
Qi Lou
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Minimum Principle ◽  
Solution Treatment ◽  
Entropy Change ◽  
Treatment Temperature ◽  
Free Energy Change ◽  
Energy Change ◽  
Solution Treatment Temperature ◽  
Gibbs Free Energy Change

The thermodynamic calculation is valuable for judging the feasibility of a reaction. In the present paper, the enthalpy change (∆HR), entropy change (∆SR) and Gibbs free energy change (∆GR) among various components in AZ91D Mg alloy-Cenosphere composites (FAC/AZ91D) were calculated. Through the calculation, we obtained the relationships between the Gibbs free energy changes and temperatures. The difficulty degree of every potential reaction could be directly reflected by the correlation curve between the temperature and the Gibbs free energy change. The analysis result provided the theoretical basis for the reaction temperature and the solution treatment temperature of the FAC/AZ91D system. At the same time, the analysis based on the minimum principle of the reaction free energy revealed the final components (MgO, Mg2Si and MgAl2O4), which was partially similar to the result of XRD analysis (MgO, Mg2Si and Mg17Al12).

Application of black walnut (Juglans nigra) husk for the removal of lead (II) ion from aqueous solution

2017 ◽  
Vol 75 (10) ◽  
pp. 2454-2464 ◽  
Author(s):  
O. S. Lawal ◽  
O. S. Ayanda ◽  
O. O. Rabiu ◽  
K. O. Adebowale
Keyword(s):  
Aqueous Solution ◽  
Entropy Change ◽  
Second Order ◽  
Black Walnut ◽  
Juglans Nigra ◽  
Ion Concentration ◽  
Batch Adsorption ◽  
Standard Entropy ◽  
Adsorption Model ◽  
Pseudo Second Order

The biosorption characteristics of Pb (II) ions from aqueous solution using black walnut (Juglans nigra) seed husk (WSH) biomass were investigated using batch adsorption techniques. The effects of pH, contact time, initial Pb (II) ion concentration, and temperature were studied. The Langmuir, Freundlich and Temkin isotherms were used to analyze the equilibrium data. It was found that the adsorption of Pb (II) ions onto WSH was best described by the Freundlich adsorption model. Biosorption kinetics data were tested using the pseudo-first order and pseudo-second order models, and it was observed that the kinetics data fitted the pseudo-second order model. Thermodynamic parameters such as standard Gibbs free energy change (ΔG0), standard enthalpy change (ΔH0) and standard entropy change (ΔS0) were evaluated. The result showed that biosorption of Pb (II) ions onto WSH was spontaneous and endothermic in nature. The FTIR study showed that the following functional groups: O-H, C = O, C-O, C-H and N-H were involved in binding Pb (II) ions to the biomass.

Kinetic Studies of Adsorption of Disperse Blue 2BLN from Aqueous Solution by Expanded Graphite

2011 ◽  
Vol 148-149 ◽  
pp. 357-360
Author(s):  
Jin Bo Huang ◽  
Min Cong Zhu ◽  
Zhi Fang Zhou ◽  
Hong Xia Zhang
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Ph Value ◽  
Expanded Graphite ◽  
Kinetic Studies ◽  
Second Order ◽  
Batch Adsorption ◽  
Initial Ph ◽  
Intra Particle Diffusion ◽  
Pseudo Second Order

Expanded graphite (EG) was prepared by microwave irradiation and evaluated as adsorbent for the removal of disperse blue 2BLN (DB) from aqueous solution by the batch adsorption technique under different conditions of initial pH value, adsorbent dosage, initial dye concentration and contact time. The experimental data were analyzed considering pseudo-first-order, pseudo-second-order and intra-particle diffusion approaches. The adsorption kinetics at room temperature could be expressed by the pseudo second order model very well. The results indicate that the adsorption rate is fast enough and more than eighty percent of the adsorbed DB can be removed in the first 15 min at room temperature, which makes the process practical for industrial application.

scholarly journals Use of Different Types of Biosorbents to Remove Cr (VI) from Aqueous Solution

Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 240
Author(s):  
Eva Pertile ◽  
Tomáš Dvorský ◽  
Vojtěch Václavík ◽  
Silvie Heviánková
Keyword(s):  
Experimental Data ◽  
Aqueous Solution ◽  
Ph Value ◽  
Juglans Regia ◽  
Chemical Activation ◽  
Second Order ◽  
Order Kinetic ◽  
Fomitopsis Pinicola ◽  
Adsorption Data ◽  
Pseudo Second Order

This article summarizes the results of a research study that was focused on the possibility of removing Cr (VI) from aqueous solution, using low-cost waste biomaterial in a batch mode. A set of seven biosorbents was used: Fomitopsis pinicola, a mixture of cones, peach stones, apricot stones, Juglans regia shells, orange peels, and Merino sheep wool. Three grain fractions (fr. 1/2, fr. 0.5/1.0, and fr. 0/0.5 mm) of biosorbents were studied. The aim was to find the most suitable biosorbent that can be tested with real samples. The influence of other factors on the course of biosorption was studied as well (chemical activation of the biosorbent, pH value, rotation speed during mixing, temperature, and the influence of biosorbent concentration). The use of chemical activation and adjustment of the pH to 1.1 to 2.0 make it possible to increase their sorption capacity and, for some biosorbents, to shorten the exposure times. Two kinetic models were used for the analysis of the experimental data, to explain the mechanism of adsorption and its possible speed control steps: pseudo-first and pseudo-second-order. The pseudo-second-order kinetic model seems to be the most suitable for the description of the experimental data. The thermodynamic parameters suggest that the biosorption was endothermic and spontaneous. In the biosorption equilibrium study, the adsorption data were described by using Langmuir and Freundlich adsorption isotherms. The Langmuir model was applicable to describe the adsorption data of all biosorbents. Both models are suitable for chemically treated sheep fleece and peach stones.

scholarly journals PENENTUAN KESETIMBANGAN, TERMODINAMIKA DAN KINETIKA ADSORPSI ARANG AKTIF TEMPURUNG KELAPA SAWIT PADA ZAT WARNA REACTIVE RED DAN DIRECT BLUE

Alotrop ◽  
2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Rensy Aula Sari ◽  
M. Lutfi Firdaus ◽  
Rina Elvia
Keyword(s):  
Free Energy ◽  
Palm Oil ◽  
Entropy Change ◽  
Enthalpy Change ◽  
Free Energy Change ◽  
Energy Change ◽  
Kinetics And Thermodynamics ◽  
Synthetic Dye ◽  
Direct Blue ◽  
Isotherm Adsorption

This perpose of this research was to know the isotherm, kinetics and thermodynamics adsorption of synthetic  dye onto activated carcoal from palm oil shell. The synthetic dye were Reactive Red and Direct Blue. The model of isotherm were Langmuir and Freundlich, kinetics adsorption tested were Pseudo orde-1 and Pseudo orde-2, and also thermodynamics were free energy change (?Go), enthalpy change (?Ho), and entropy change (?So). The dominant isotherm adsorption was isotherm Freundlich, kinetic adsorption Pseudo 2 th order  with the value (?So), (?Go) and (?Ho), Reactive Red were 0,0028 Kj/mol.K , -3,93 Kj/mol, and -36,12 Kj/mol respectively. Whereas in direct blue were 0,0034 Kj/mol.K, -1,67 Kj/mol,and -30,16 Kj/mol respectively. 

scholarly journals Coconut shell-based activated carbon as adsorbent for the removal of dye from aqueous solution: equilibrium, kinetics, and thermodynamic studies

2021 ◽  
Vol 39 (4) ◽  
pp. 1076-1084
Author(s):  
O. Oribayo ◽  
O.O. Olaleye ◽  
A.S. Akinyanju ◽  
K.O. Omoloja ◽  
S.O. Williams
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Activated Carbon ◽  
Kinetic Data ◽  
Ph Value ◽  
Waste Water Treatment ◽  
Second Order ◽  
Coconut Shell ◽  
Isotherm Models ◽  
Pseudo Second Order

The need to develop more efficient adsorbent, comparable to commercially available adsorbent, is attracting significant interest as promising adsorbent for waste water treatment. In this study, the potential of activated carbon prepared from waste coconut shell (CSAC) for the removal of methylene blue (Mb) from aqueous solution was reported. Batch experiments were conducted to determine the adsorption isotherm and kinetics of Mb on CSAC. Langmuir, Freundlich and Temkin isotherm models were employed to fit and analyze the adsorption equilibrium data. The result shows Langmuir isotherm model gave the best fit and an adsorption capacity of 320.5 mg/g was obtained for Mb at pH value of 7, 0.02 g adsorbent dosage and contact time of 4.5 hour. The experimental kinetic data at different initial Mb concentrations was also analyzed with pseudo-first order, pseudo-second order and intraparticle diffusion models. The obtained results showed that the pseudo-second order model fits the adsorption kinetic data with R2 range of0.9985-0.9996. Finally, the thermodynamic parameters show that the adsorption of Mb on CSAC was spontaneous and endothermic in nature. This therefore suggests that (CSAC) is a viable adsorbent for effective removal of dye from wastewater effluent. Keywords: Activated carbon, Adsorption isotherms, Coconut shells, Methylene blue, kinetics.

The enol content of simple carbonyl compounds: a thermochemical approach

1979 ◽  
Vol 57 (2) ◽  
pp. 240-248 ◽  
Author(s):  
J. Peter Guthrie ◽  
Patricia A. Cullimore
Keyword(s):  
Aqueous Solution ◽  
Free Energy ◽  
Carbonyl Compounds ◽  
Free Energy Change ◽  
Energy Change ◽  
Free Energies ◽  
Enol Ethers ◽  
Free Energy Of Formation ◽  
Hydrolysis Of ◽  
Energy Of Formation

From the heats of hydrolysis of enol ethers, the heats of formation of the enol ethers, and thence the free energies of formation of the enol ethers in aqueous solution can be calculated. For this calculation it was necessary to determine the free energies of transfer from the gas phase to aqueous solution. By methods previously published it was possible to estimate the free energy change for the hypothetical hydrolysis reaction leading from the enol ether to the enol, which in turn made possible calculation of the free energy of formation of the enol. Finally the free energy change for enolization in aqueous solution could be calculated using the known free energy of formation of the corresponding keto tautomer. In this way the following were determined: carbonyl compound, pKenol = −log ([enol]/[keto]): acetaldehyde, 5.3; propionaldehyde, 3.9; isobutyraldehyde, 2.8; acetone, 7.2; 2-butanone, 8.3; 3-pentanone, 7.8; cyclopentanone, 7.2; cyclohexanone, 5.7; acetophenone, 6.7.

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