scholarly journals Adsorption of Methylene Blue on the Composite Sorbent Based on Bentonite-Like Clay and Hydroxyapatite

2018 ◽  
Vol 18 (4) ◽  
pp. 733 ◽  
Author(s):  
Alexandr Ivanovich Vezentsev ◽  
Dang Minh Thuy ◽  
Lidia Fedotovna Goldovskaya-Peristaya ◽  
Nadezhda Alexandrovna Glukhareva
Keyword(s):  
Methylene Blue ◽  
Order Reaction ◽  
Composite Sorbent ◽  
Second Order Reaction ◽  
Isotherm Equation ◽  
Kinetic And Thermodynamic Parameters ◽  
Langmuir Isotherm Equation ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Maximal Sorption Capacity

The adsorption of methylene blue from model aqueous solutions on bentonite-like clay, hydroxyapatite, and a composite sorbent has been investigated. The kinetic and thermodynamic parameters of adsorption in the temperature range 298–333 К have been calculated. The process is found to obey Langmuir isotherm equation. It is spontaneous but slightly endothermic. The maximal sorption capacity of the composite sorbent toward methylene blue is 175.4 mg/g at 25 °С that is 1.3 times more than that for bentonite-like clay and 17.8 times more than that for hydroxyapatite. Kinetics of the process is due to the combination of external and internal diffusion and can be described better by the model of pseudo-second order reaction.

Thermo-Kinetic Study of Adsorption of Methylene Blue in Aqueous Solutions Using Algerian Illite Natural and Activated Mineral Clay

2021 ◽  
Vol 406 ◽  
pp. 348-363
Author(s):  
Larbi Haddad ◽  
Abdelkader Hima ◽  
Belkhir Dadamoussa ◽  
Asma Messai Aoun
Keyword(s):  
Methylene Blue ◽  
Specific Area ◽  
Experimental Results ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Isotherm Equation ◽  
Langmuir Isotherm Equation ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Two Stages

In this study, a local mineral clay was used as an adsorbent for the elimination of a cationic dye: methylene blue (MB), in an aqueous solution by adsorption technique. Early on, we performed mineralogical and textural analyses of a clay sample using various techniques, namely X-ray diffraction, Brunauer-Emmett-Teller analysis and Fourier-transform infrared spectroscopy. The experimental results showed that this adsorbent is a mesoporous and non-swelling clay with illite and kaolinite as the major components with a specific area of about 110m2/g. The study of MB adsorption on the clay was carried out by optimizing the conditions of adsorption, notably the initial concentration of pollutant C0, the mass of clay m, the contact time t, the potential of hydrogen of the solution pH and the temperature T. Experimental results have shown that the equilibrium data are well adjusted by a Langmuir isotherm equation. Thermodynamic parameters such as the changes in Gibbs free energy, enthalpy, and entropy were determined from batch experiments. Results revealed that the adsorption of MB onto illitic clay was endothermic and spontaneous process. Kinetic modeling was also carried out. Experimental data adjusted the kinetic model of pseudo-second order with two stages of intraparticle diffusion.

scholarly journals Translocation of Cations During Sorption of Copper in the System Solution - Algae (Spirogyra sp.)/Translokacja Kationów Podczas Procesu Sorpcji Miedzi W Układzie Roztwór - Glony (Spirogyra Sp.)

2014 ◽  
Vol 21 (3) ◽  
pp. 425-433
Author(s):  
Małgorzata Rajfur ◽  
Andrzej Kłos ◽  
Jan Kříž
Keyword(s):  
Order Reaction ◽  
Static System ◽  
Second Order Reaction ◽  
System Solution ◽  
Fixed Proportion ◽  
Pseudo Second Order ◽  
The Difference ◽  
Kinetics Of ◽  
Copper Cations ◽  
Solution Volume

Abstract Kinetics of the sorption of copper cations in Spirogyra sp. algae was analysed, together with the accompanying processes of hydrogen cations sorption and releasing to the solution the cations bonded in the algae: Na+, Mg2+, K+ and Ca2+. It was established that, in a static system, at the fixed proportion of algae mass to the solution volume, these processes occur simultaneously, however presumably the quantity of the released salts influences the parameters of heterophase equilibrium of ion exchange. In the experiment conditions, the quantity of the released cations was nearly 10 times larger than the quantity of the sorbed cations. The equilibrium parameters, determined from the model of pseudo second order reaction, were compared with the parameters obtained after 30 min of the process duration, ie at relatively stable indications of measuring equipment. On the example of the sorbed copper, the difference is approximately 8%. It was confirmed that the solution conductivity is a good parameter for the estimation of the state close to equilibrium.

scholarly journals KINETIKA FOTODEGRADASI METHYLENE BLUE MENGGUNAKAN KOMPOSIT Ag3PO4/Ag/HAp TULANG IKAN KAKAP MERAH (Lutjanus sp.)

2020 ◽  
Vol 12 (2) ◽  
Author(s):  
Stoflly E. M. Pangajow ◽  
Audy Wuntu ◽  
Meiske S. Sangi
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Reaction Kinetics ◽  
Fish Bone ◽  
Order Reaction ◽  
Kinetics Model ◽  
Light Radiation ◽  
Second Order Reaction ◽  
Bone Powder ◽  
Kinetics Of

ABSTRAKTujuan dari penelitian ini untuk mengkaji kinetika fotodegradasi methylene blue (MB) menggunakan komposit Ag3PO4/Ag/HAp tulang ikan kakap merah (Lutjanus sp.).  Serbuk tulang ikan yang dikalsinasi hingga 1000ºC dan direaksikan dengan AgNO3 dengan rasio mol 5:1 (Ag:HAp) dan dihasilkan komposit Ag3PO4/Ag/HAp. Larutan MB diinteraksikan dengan komposit dengan variasi waktu 5-180 menit dibawah radiasi cahaya tampak. Konsentrasi MB yang tersisa ditentukan ditentukan dengan spektrofotometer UV-Vis dan data yang diperoleh dianalisis dengan model kinetika reaksi orde ke-1 dan ke-2. Hasil penelitian menunjukkan bahwa fotodegradasi MB oleh komposit Ag3PO4/Ag/HAp mengikuti model kinetika fotodegradasi orde ke-2. ABSTRACT The purpose of this research was to study the kinetics of methylene blue (MB) photodegradation using composite Ag3PO4/Ag/HAp bone fish of red snapper (Lutjanus sp.). Fish bone powder which was calcined to 1000ºC and reacted with AgNO3 with mole ratio of 5 : 1 (Ag: HAp) and produced Ag3PO4/Ag/HAp composite. MB solution was interacted with composites with variation of time 5-180 minutes under visible light radiation. The remaining MB concentrations determined were determined by a UV-Vis spectrophotometer and the data obtained were analyzed with first and second order reaction kinetics model. The results showed that MB photodegradation by Ag3PO4/Ag/HAp composites followed the 2nd order photodegradation kinetics model. 

Removal of methylene blue by adsorption on aluminosilicate waste: equilibrium, kinetic and thermodynamic parameters

2016 ◽  
Vol 74 (10) ◽  
pp. 2437-2445 ◽  
Author(s):  
Carlos Alberto Policiano Almeida ◽  
Tânia Marina Palhano Zanela ◽  
Clodoaldo Machado ◽  
Juan Antônio Altamirano Flores ◽  
Luiz Fernando Scheibe ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Thermodynamic Parameters ◽  
Low Cost ◽  
Order Kinetic ◽  
X Ray ◽  
Isotherm Equation ◽  
First Order ◽  
Kinetic And Thermodynamic Parameters ◽  
Langmuir Isotherm Equation ◽  
Pseudo First Order

An aluminosilicate waste (AW) was investigated as adsorbent for methylene blue (MB) dye. AW was characterized by petrography, X-ray diffractometry, X-ray fluorescence, scanning electron microscopy, thermogravimetry and zeta potential measurements. It was found that AW contains kaolinite, and other minor components such as quartz, muscovite, smectite, siderite, pyrite and organic compounds. The chemical composition of AW is mainly SiO2 (49%) and Al2O3 (23%) and it has negative superficial charge above pH 1.73. Adsorption of MB dye was studied in a batch system under different conditions of initial dye concentration, contact time and temperature. The isothermal data from batch experiments were fitted to Langmuir and Freundlich equations, with a better fit shown by the Langmuir isotherm equation. Also, pseudo-first-order, pseudo-second-order and intraparticle diffusion models were considered to evaluate the rate parameters. The experimental data fitted the pseudo-first-order kinetic model best. Thermodynamic parameters were calculated, showing the adsorption to be an endothermic yet spontaneous process, with the activation energy of +37.8 kJ mol–1. The results indicate that AW adsorbs MB efficiently, and can be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.

Kinetics of the reaction between hexamethylenediisocyanate and 1-pentanol

1983 ◽  
Vol 48 (11) ◽  
pp. 3279-3286
Author(s):  
Slavko Hudeček ◽  
Miloslav Bohdanecký ◽  
Ivana Hudečková ◽  
Pavel Špaček ◽  
Pavel Čefelín
Keyword(s):  
Liquid Chromatography ◽  
Rate Constants ◽  
Reversed Phase ◽  
Order Reaction ◽  
Second Order ◽  
Second Order Reaction ◽  
Reversed Phase Liquid Chromatography ◽  
Consecutive Reactions ◽  
Phase Liquid ◽  
Kinetics Of

The reaction between hexamethylenediisocyanate and 1-pentanol in toluene was studied by means of reversed-phase liquid chromatography. By employing this method, it was possible to determine all components of the reaction mixture including both products, i.e. N-(6-isocyanate hexyl)pentylcarbamate and N,N'-bis(pentyloxycarbonyl)hexamethylenediamine. Relations for the calculation of kinetic constants were derived assuming a competitive consecutive second-order reaction. It was demonstrated that the reaction involved in this case is indeed a second-order reaction, and the rate constants of the first and second consecutive reactions were determined.

scholarly journals Biosorption and Diffusion Modeling of Pb(II) by Malt Bagasse

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Klaiani B. Fontana ◽  
Giane Gonçalves Lenzi ◽  
Erica R. L. R. Watanabe ◽  
Ervin Kaminski Lenzi ◽  
Juliana A. M. T. Pietrobelli ◽  
...  
Keyword(s):  
Sorption Process ◽  
Isotherm Models ◽  
Diffusion Modeling ◽  
Biosorption Capacity ◽  
Kinetic And Thermodynamic Parameters ◽  
Pseudo Second Order ◽  
Ph Optimization ◽  
Kinetics Of ◽  
And Diffusion

The removal of Pb(II) from water by biosorption processes onto malt bagasse was investigated and the kinetic and thermodynamic parameters were obtained; additionally a diffusion modeling was proposed. The characterization of malt bagasse was performed by FTIR and SEM/EDS. The experiments were conducted in batch system and an experimental design based response surface methodology was applied for agitation speed and pH optimization. The kinetics of biosorption followed pseudo-second-order model and the temperature of the process affected the biosorption capacity. Isotherm models of Langmuir, Freundlich, and Elovich were applied and the Langmuir model showed better fit and the estimated biosorption capacity was 29.1 mg g−1. The negative values obtained for ΔG° and positive values of ΔH° confirm, respectively, the spontaneous and endothermic nature of the process. The diffusion modeling was performed based on experiments in the absence of agitation to investigate the influence of the biosorbent on the sorption process of Pb(II) ions.

scholarly journals Water defluoridation by alumina modified Turkey clinoptilolite: equilibrium, kinetic models and experimental design approaches

2017 ◽  
Vol 18 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Selim Selimoglu ◽  
Esra Bilgin Simsek ◽  
Ulker Beker
Keyword(s):  
Natural Zeolite ◽  
Kinetic Studies ◽  
Order Reaction ◽  
Operating Conditions ◽  
Second Order Reaction ◽  
Freundlich Model ◽  
Box Behnken Design ◽  
Fluoride Adsorption ◽  
Exothermic Process ◽  
Pseudo Second Order

Abstract In the current work, alumina modified natural zeolite (Z-Al) was used for fluoride adsorption in aqueous solution. Effects of process parameters such as pH, temperature, initial concentration and contact time were investigated. Box–Behnken design was found effective in defining the operating conditions for fluoride sorption onto Z-Al. Confirmatory experiments were conducted to examine the reliability of the regression equation. The predicted (2.261 mg g−1) and experimental (2.289 mg g−1) capacities were found to be similar, demonstrating the accuracy of the model. The fluoride adsorption onto Z-Al was well described by the Freundlich model. Kinetic studies revealed that the adsorption followed a pseudo-second-order reaction. Thermodynamic parameters depicted that the fluoride adsorption on the alumina modified zeolite was a spontaneous and exothermic process. The co-existing ions affected the defluoridation performance significantly. Regeneration of exhausted Z-Al was achieved with H2SO4.

scholarly journals SOLVATION OF THE [Cr(NCS)4(IMIDAZOLE)2] ION IN ETHANOL-WATER MIXTURES

2002 ◽  
Vol 10 (11) ◽  
pp. 63-72
Author(s):  
lon Ganescu ◽  
George Bratulescu ◽  
Ion Papa ◽  
Anca Ganescu ◽  
Alin Barbu ◽  
...  
Keyword(s):  
Kinetic Parameters ◽  
Order Reaction ◽  
Water Molecules ◽  
Hydrogen Ions ◽  
Second Order Reaction ◽  
Acidic Solutions ◽  
The Third ◽  
Competitive Reactions ◽  
Different Temperatures ◽  
Kinetics Of

Salvation kinetics of [Cr(NCS)4(imidazole)2]- has been studied in ethanol-water mixtures at different temperatures. The first stage of the solvation consists of two competitive reactions: two NCS- ions are exchanged, presumably, by water molecules and simultaneously an imidazole molecule by ethanol, the latter in a second-order reaction, accelerated by hydrogen ions. The exchange of the amine is followed by the substitution of the first two NCS- ions. The third and fourth NCS- ions are substituted only in neutral and slightly acidic solutions. Kinetic parameters have been determined for reactions (1), (2), and (4). The influence of the solvent composition and acidity is discussed

scholarly journals The alcoholysis of 1,2,2-trimethylpropyl-methylfluorophosphonate

2000 ◽  
Vol 65 (12) ◽  
pp. 857-866
Author(s):  
Mladjen Micevic ◽  
Slobodan Petrovic
Keyword(s):  
Kinetic Data ◽  
Reaction Rate ◽  
Frequency Factor ◽  
Reaction Rate Constant ◽  
Order Reaction ◽  
Activation Entropy ◽  
Second Order Reaction ◽  
Third Order ◽  
First Order ◽  
Kinetics Of

The alcoholysis of 1,2,2-trimethylpropyl-methylfluorophosphonate (soman) was examined with a series of alkoxides and in corresponding alcohols: methanol, ethanol, 1-propanol, 2-propanol, 2-methoxyethanol and 2-ethoxyethanol. Soman reacts with the used alkoxides in a second order reaction, first order in each reactant. The kinetics of the reaction between 1,2,2-trimethylpropyl-methylfluorophosphonate and ethanol in the presence of diethylenetriamine was also examined. A third order reaction rate constant was calculated, first order in each reactant. The activation energy, frequency factor and activation entropy were determined on the basis of the kinetic data.

scholarly journals The Adsorption of Methylene Blue on Eco-Friendly Reduced Graphene Oxide

Nanomaterials ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 681 ◽  
Author(s):  
Fabian Arias Arias ◽  
Marco Guevara ◽  
Talia Tene ◽  
Paola Angamarca ◽  
Raul Molina ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Maximum Adsorption Capacity ◽  
Green Protocol ◽  
Reduced Graphene ◽  
Wastewater Systems ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Potential Use

Recently, green-prepared oxidized graphenes have attracted huge interest in water purification and wastewater treatment. Herein, reduced graphene oxide (rGO) was prepared by a scalable and eco-friendly method, and its potential use for the removal of methylene blue (MB) from water systems, was explored. The present work includes the green protocol to produce rGO and respective spectroscopical and morphological characterizations, as well as several kinetics, isotherms, and thermodynamic analyses to successfully demonstrate the adsorption of MB. The pseudo-second-order model was appropriated to describe the adsorption kinetics of MB onto rGO, suggesting an equilibrium time of 30 min. Otherwise, the Langmuir model was more suitable to describe the adsorption isotherms, indicating a maximum adsorption capacity of 121.95 mg g−1 at 298 K. In addition, kinetics and thermodynamic analyses demonstrated that the adsorption of MB onto rGO can be treated as a mixed physisorption–chemisorption process described by H-bonding, electrostatic, and π − π interactions. These results show the potential of green-prepared rGO to remove cationic dyes from wastewater systems.

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