scholarly journals Kinetic Study of Photocatalytic Degradation of Tolonium Chloride Under High Pressure Irradiation in Aquatic Buffer Systems

2011 ◽  
Vol 8 (s1) ◽  
pp. S19-S26 ◽  
Author(s):  
M. Montazerozohori ◽  
S. Nezami ◽  
S. Mojahedi
Keyword(s):  
High Pressure ◽  
Photocatalytic Degradation ◽  
Kinetic Study ◽  
Rate Constants ◽  
Order Kinetic ◽  
Optimum Conditions ◽  
First Order ◽  
Reactor Cell ◽  
Order Kinetic Model ◽  
Tolonium Chloride

Anatase titanium dioxide catalyzed photodegradation of tolonium chloride at various bufferic pH of 2, 7, 9 and 12 in aqueous solution is presented. The effect of some physicochemical parameters such as initial concentration of dye, catalyst amount and reaction time on photocatalytic degradation has been investigated in a photo-reactor cell containing high pressure mercury lamp to obtain the optimum conditions in each bufferic pH at constant temperature. A complete spectrophotometric kinetic study of tolonium chloride under high pressure irradiation at buffer media was performed. The photocatalytic degradation observed rate constants (kobs) were found to be 2.90×10-3, 3.30×10-3, 3.20×10-3and 5.20×10-3min-1for buffer pH of 2-12 respectively. It was found that a pseudo-first-order kinetic model based on Langmuir-Hinshelwood one is usable to photodegradation of this compound at all considered buffer pH. In addition to these, the Langmuir-Hinshelwood rate constants, krfor the titled compound at various pH are reported.

Photocatalytic Degradation of Methyl Violet with H3PW6Mo6O40/SiO2 Sensitized by H2O2

2013 ◽  
Vol 709 ◽  
pp. 70-73
Author(s):  
Guo Bin Duan ◽  
Yong Kui Huang ◽  
Li Yu ◽  
Shui Jin Yang
Keyword(s):  
Photocatalytic Degradation ◽  
Degradation Rate ◽  
Sol Gel ◽  
Methyl Violet ◽  
Light Irradiation ◽  
Natural Light ◽  
Order Kinetic ◽  
Initial Concentration ◽  
First Order ◽  
Order Kinetic Model

H3PW6Mo6O40/SiO2 was prepared by sol-gel method, and sensitized by H2O2 solution. The photocatalytic degradation of methyl violet by H3PW6Mo6O40/SiO2 under simulated natural light irradiation was investigated. The results demonstrated that at optimal condition (initial concentration of methyl violet is 10 mg/L, and the pH is 2.5, the dosage of catalyst is 0.5% based on feed stocks), the degradation rate of methyl violet is as high as 88.7 % after 2.5h simulated natural light irradiation. The reaction of photocatalysis for methyl violet can be expressed as first-order kinetic model.

scholarly journals A study of photocatalytic degradation of textile dye CI basic yellow 28 in water using P160 TiO2 based catalyst

2012 ◽  
Vol 77 (12) ◽  
pp. 1747-1757 ◽  
Author(s):  
Veljko Djokic ◽  
Jelena Vujovic ◽  
Aleksandar Marinkovic ◽  
Rada Petrovic ◽  
Djordje Janackovic ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Textile Dye ◽  
Order Kinetic ◽  
Operational Parameters ◽  
First Order ◽  
Photodegradation Rate ◽  
Vis Spectroscopy ◽  
Langmuir Hinshelwood Mechanism ◽  
Order Kinetic Model ◽  
Alkaline Conditions

The photocatalytic degradation of synthetic textile dye CI Basic Yellow 28 (BY28) in water, using recently synthesized P160 TiO2 based catalyst, under Osram ultra-vitalux? lamp (300 W) light, was studied. The effect of the operational parameters such as initial concentration of catalyst, initial dye concentration and pH was studied. Salt effect was also investigated (NaCl, Na2CO3, Na2SO4, NaNO3). It was found that the optimal concentration of catalyst is 2.0 g L-1. A pseudo first-order kinetic model was illustrated using the Langmuir-Hinshelwood mechanism, and the adsorption equilibrium constant and the rate constant of the surface reaction were calculated (KBY = 6.126 L mg-1 and kC = 0.272 mg L-1 min-1, respectively). The photodegradation rate was higher in weak acidic than in high acidic and alkaline conditions. The presence of CO32- ions increases the photodegradation rate while Cl-, SO42- and NO3-ions decreases the reaction rate. The rate of photodegradation of BY28 was measured using UV-Vis spectroscopy.

Catalytic Degradation of Pyrrole in Aqueous Solution by Cu/SBA-15

2015 ◽  
Vol 13 (3) ◽  
pp. 437-445 ◽  
Author(s):  
Shweta Garg ◽  
Vimal Chandra Srivastava ◽  
Seema Singh ◽  
Tapas Kumar Mandal
Keyword(s):  
Hydrogen Peroxide ◽  
Thermal Analyses ◽  
Stoichiometric Ratio ◽  
Order Kinetic ◽  
Optimum Conditions ◽  
Thermo Gravimetric ◽  
First Order ◽  
Operating Variables ◽  
Order Kinetic Model

Abstract Present study reports parametric and kinetic study for catalytic per oxidation (CPO) of pyrrole by Cu/SBA-15 catalyst using H2O2 as an oxidant. Brunauer-Emmett-Teller surface area, Fourier transform infra-red spectroscopy and thermo gravimetric-differential thermal analyses were used for the characterization of catalyst. Effects of various operating variables such as initial concentration of pyrrole (Co): 48.3–386.8 mg/L, catalytic dose (Cw): 0.5–2 g/L, stoichiometric ratio of hydrogen peroxide/pyrrole: 1–4, and reaction temperature (T): 50–60°C were studied. More than 85% pyrrole mineralization was observed at the optimum conditions of Cw = 1.5 g/L, stoichiometric ratio of hydrogen peroxide/pyrrole = 3, T = 55°C at pH = 6.1. A two-step pseudo-first-order kinetic model well-described the pyrrole mineralization by the CPO process.

Kinetic Study of the Adsorption of Dye onto Cotton in SDS-CTAB Reverse Micelles

2015 ◽  
Vol 723 ◽  
pp. 591-595
Author(s):  
Zu Lan Liu ◽  
Lan Qian Li ◽  
Yi Ping Liu ◽  
Ming Lu
Keyword(s):  
Kinetic Study ◽  
Adsorption Kinetics ◽  
Reverse Micelles ◽  
Adsorption Kinetic ◽  
Order Kinetic ◽  
First Order ◽  
Reactive Blue 19 ◽  
Order Kinetic Model ◽  
Pseudo First Order ◽  
Kinetics Of

Adsorption kinetic study of C.I. reactive blue 19 onto cotton was carried out in SDS-CTAB reverse micelles. The data of adsorption kinetics were examined using pseudo first-and second-order kinetic models. It was found that the adsorption kinetics of dye on cotton with diffusion controlling follows the pseudo first-order kinetic model.

scholarly journals Nitrogen Removal in a Horizontal Subsurface Flow Constructed Wetland Estimated Using the First-Order Kinetic Model

2016 ◽  
Author(s):  
Lijuan Cui ◽  
Wei Li ◽  
Yaqiong Zhang ◽  
Jiaming Wei ◽  
Yinru Lei ◽  
...  
Keyword(s):  
Kinetic Model ◽  
Rate Constant ◽  
Constructed Wetland ◽  
Rate Constants ◽  
Removal Rate ◽  
Order Kinetic ◽  
First Order ◽  
N Removal ◽  
Order Kinetic Model ◽  
Beijing China

We monitored the water quality and hydrological conditions of a horizontal subsurface constructed wetland (HSSF-CW) in Beijing, China, for 2 years. We simulated the area rate constant and the temperature coefficient with the first-order kinetic model. We examined the relationships between the nitrogen (N) removal rate, N load, seasonal variations in the N removal rate, and environmental factors, such as the area rate constant, temperature, and dissolved oxygen (DO). The effluent ammonia (NH4+-N) and nitrate (NO3−-N) concentrations were significantly lower than the influent concentrations (p<0.01, n=38). The NO3−-N load was significantly correlated with the removal rate (R2=0.9566, p<0.01), but the NH4+-N load was not correlated with the removal rate (R2=0.0187, p>0.01). The area rate constants of NO3−-N and NH4+-N at 20 °C were 27.01±26.49 and 16.63±10.58 m∙yr−1, respectively. The temperature coefficients for NO3−-N and NH4+-N were estimated at 1.0042 and 0.9604, respectively. The area rate constants for NO3−-N and NH4+-N were not correlated with temperature (p>0.01). The NO3−-N area rate constant was correlated with the corresponding load (R2=0.9625, p<0.01). The NH4+-N area rate was correlated with DO (R2=0.6922, p<0.01), suggesting that the factors that influenced the N removal rate in this wetland met Liebig's law of the minimum.

scholarly journals Fractional kinetics of photocatalytic degradation

2018 ◽  
Vol 08 (05) ◽  
pp. 1850034 ◽  
Author(s):  
C. L. Wang
Keyword(s):  
Kinetic Model ◽  
Photocatalytic Degradation ◽  
Degradation Process ◽  
Order Kinetic ◽  
Material Parameters ◽  
First Order ◽  
Fractional Kinetics ◽  
Order Kinetic Model ◽  
Kinetics Of ◽  
Degradation Time

In this paper, photocatalytic degradation processes of different materials are fitted to the first-order kinetic model, second-order kinetic model and fractional first-order kinetic model. Deterministic coefficients are calculated for the evaluation of the validity of these models. The fitting results show clearly that the degradation process can fit the fractional first-order kinetic model in a very good manner. In this way, two material parameters can be well defined. One is the degradation time, which can be used to describe the photocatalytic degradation process quantitatively. Another is the order of the derivative, which could be related to the material’s microstructure.

scholarly journals Minerals as Potential Catalysts in Heterogeneous Catalytic Ozonation: A Kinetic Study of p-CBA Degradation in Aqueous Solutions at pH 7

2021 ◽  
Vol 5 (1) ◽  
pp. 5
Author(s):  
Savvina Psaltou ◽  
Efthimia Kaprara ◽  
Manassis Mitrakas ◽  
Anastasios Zouboulis
Keyword(s):  
Kinetic Model ◽  
Kinetic Study ◽  
Raw Materials ◽  
Catalytic Ozonation ◽  
Second Order ◽  
Order Kinetic ◽  
First Order ◽  
Heterogeneous Catalytic ◽  
Order Kinetic Model ◽  
Pseudo Second Order

This study examines the removal of p-CBA via the application of heterogeneous catalytic ozonation in the presence of 13 minerals. The solids were used as raw materials or after hydrophilic/hydrophobic modification. The optimal minerals were zeolite, calcite, dolomite, and thermally treated talc. The kinetic study showed that the decomposition of ozone followed a first-order kinetic model for all ozonation systems, whereas the kinetic model of p-CBA removal depended on the materials that were applied. The catalytic degradation of p-CBA followed a second-order kinetic model, while in the presence of non-catalytic materials; the p-CBA abatement was in best agreement with the pseudo-second-order kinetic model, as single ozonation.

scholarly journals Enhanced photocatalytic degradation of doxycycline using a magnetic polymer-ZnO composite

2018 ◽  
Vol 2017 (3) ◽  
pp. 791-801 ◽  
Author(s):  
Ali Mohammadi ◽  
Shabnam Pourmoslemi
Keyword(s):  
Aqueous Solution ◽  
Photocatalytic Degradation ◽  
Extraction Efficiency ◽  
Nano Particles ◽  
Order Kinetic ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Polymer Precipitation ◽  
Order Kinetic Model

Abstract A novel magnetic polymer-ZnO composite was prepared by incorporating Fe3O4 and ZnO nano-particles in the structure of an adsorbent polymer. Precipitation polymerization was used for synthesizing the adsorbent polymer and its efficiency for extracting doxycycline from aqueous solution was optimized according to several parameters including time, pH and amount of polymer. Results showed the highest extraction efficiency at neutral pH of the doxycycline solution in 20 min, and the capacity of the polymer was about 20 mg/g. The magnetic property of a material is important for fast and facile separation of composite particles after each use. Magnetic polymer-ZnO composite was synthesized by adding Fe3O4 and ZnO nano-particles to the polymerization mixture in order to take advantage of both sorption and photocatalytic degradation mechanisms. The obtained composite was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy equipped with wavelength dispersive X-ray spectroscopy and used for enhanced photocatalytic degradation of doxycycline in aqueous solution. Results showed 76.5% degradation of doxycycline in 6 hours which was significantly higher than the degradation observed by an equivalent amount of ZnO nano-particles. Photocatalytic degradation of doxycycline fitted the pseudo first order kinetic model with a rate constant of 4 × 10−3 μg mL−1 min−1.

scholarly journals Photocatalytic Removal of Microcystin-LR by Advanced WO3-Based Nanoparticles under Simulated Solar Light

2015 ◽  
Vol 2015 ◽  
pp. 1-9
Author(s):  
Chao Zhao ◽  
Dawei Li ◽  
Yonggang Liu ◽  
Chuanping Feng ◽  
Zhenya Zhang ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Photocatalytic Oxidation ◽  
Chloride Ion ◽  
Solar Light ◽  
Order Kinetic ◽  
First Order ◽  
Simulated Solar Light ◽  
Photocatalytic Removal ◽  
Order Kinetic Model ◽  
Purification Of Water

A series of advanced WO3-based photocatalysts including CuO/WO3, Pd/WO3, and Pt/WO3were synthesized for the photocatalytic removal of microcystin-LR (MC-LR) under simulated solar light. In the present study, Pt/WO3exhibited the best performance for the photocatalytic degradation of MC-LR. The MC-LR degradation can be described by pseudo-first-order kinetic model. Chloride ion (Cl−) with proper concentration could enhance the MC-LR degradation. The presence of metal cations (Cu2+and Fe3+) improved the photocatalytic degradation of MC-LR. This study suggests that Pt/WO3photocatalytic oxidation under solar light is a promising option for the purification of water containing MC-LR.

scholarly journals Treatability of Biodiesel Wastewaters By Using KMnO4 And KMnO4/O3 Processes And Kinetic Analysis

2021 ◽  
Author(s):  
Pınar N. TANATTI
Keyword(s):  
Reaction Time ◽  
Potassium Permanganate ◽  
Rate Constants ◽  
Reaction Rate ◽  
Suitable Model ◽  
Order Kinetic ◽  
Optimum Conditions ◽  
Reaction Rate Constants ◽  
Order Kinetic Model ◽  
Removal Efficiencies

Abstract The purpose of this study is to investigate the treatability of electrocoagulated biodiesel wastewater (ECBD) by potassium permanganate (KMnO4) and potassium permanganate/ozone (KMnO4/O3) processes. The ECBD removal efficiencies of both combined method and KMnO4 methods were compared and the KMnO4/O3 process gave better results than the KMnO4 process. For the ECBD removal efficiencies, the experimental parameters including pH, potassium permanganate dose, ozone dose and reaction time parameters were optimized by changing the one parameter at a time. As a result of 6 h of KMnO4 oxidation, 91.74% of COD and 95.93% of MeOH removal was achieved under the optimum conditions (pH 2, 5 g/L KMnO4 dose). However, under optimum conditions (pH 13, 2 g/L KMnO4 dose, 3000 mg/L O3 dose, 6 h reaction time), the COD and MeOH removal efficiencies have been obtained for KMnO4/O3 as 97.79% and 98.30%, respectively. The second order kinetic model has been found to be the most suitable model for both processes and the regression coefficients (R2) has been found as 0.999 and 0.999 for KMnO4 and KMnO4/O3, respectively. The reaction rate constants (k) have been also calculated as 6x10-5 L/mg.min and 1.63x10-4 L/mg.min for COD and MeOH in KMnO4 oxidation, respectively. Furthermore, the reaction rate constants (k) have been also calculated as 6x10-5 L/mg.min and 1.6x10-4 L/mg.min for COD and MeOH in KMnO4/O3 oxidation, respectively.

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