scholarly journals Influence of Operating Parameters on Photocatalytic Oxidation of 2,4-Dichlorofenol in Aqueous Solution by TiO2/Stainless Steel Photocatalytic Membrane

2021 ◽  
Vol 11 (24) ◽  
pp. 11664
Author(s):  
Liliana Bobirică ◽  
Constantin Bobirică ◽  
Giovanina Iuliana Lupu ◽  
Cristina Orbeci
Keyword(s):  
Stainless Steel ◽  
Photocatalytic Degradation ◽  
Photocatalytic Oxidation ◽  
Oxidation Process ◽  
Organic Substrate ◽  
Molar Ratio ◽  
Operating Parameters ◽  
Photocatalytic Reactor ◽  
Initial Concentration ◽  
Working Solution

The influence of some operating parameters of an UV photocatalytic reactor with TiO2/stainless steel photocatalytic membrane on the photocatalytic oxidation of 2,4-dichlorophenol from aqueous solutions was studied in this paper. It was shown that the pH of the working solution substantially influences the photocatalytic degradation of the organic substrate, with the degradation efficiency increasing with decreasing the pH of the working solution by a maximum corresponding to pH 3. The rate constant of the photocatalytic oxidation process is about twice as high at pH 3 comparative with pH 7 for the same initial concentration of the organic substrate. The molar ratio of hydrogen peroxide/organic substrate also influences the photocatalytic oxidation process of the organic substrate. The results obtained in this paper highlight the fact that a stoichiometric molar ratio is favorable for the photocatalytic degradation of 2,4-dichlorophenol. It has also been shown that the initial concentration of the organic substrate influences the rate of photocatalytic degradation. It appears that the rate of photocatalytic degradation decreases with the increasing of initial concentration of 2,4-dichlorophenol.

Use of Experimental Designs to Establish a Kinetic Law for a Gas Phase Photocatalytic Process

2014 ◽  
Vol 12 (1) ◽  
pp. 113-122 ◽  
Author(s):  
Cécile Raillard ◽  
Audrey Maudhuit ◽  
Valérie Héquet ◽  
Laurence Le Coq ◽  
Jean Sablayrolles ◽  
...  
Keyword(s):  
Light Intensity ◽  
Photocatalytic Degradation ◽  
Gas Phase ◽  
Photocatalytic Oxidation ◽  
Experimental Designs ◽  
Photocatalytic Process ◽  
Air Velocity ◽  
Kinetic Rate ◽  
Initial Concentration ◽  
Designs Of Experiments

Abstract The photocatalytic degradation of three common indoor VOCs – acetone, toluene and heptane – is investigated in a dynamic photocatalytic oxidation loop using Box–Behnken designs of experiments. Thanks to the experimental results and the establishment of a kinetic rate law based on a simplified mechanism, a predictive model for the VOC degradation involving independent factors is developed. The parameters under investigation are initial concentration, light intensity and air velocity through the photocatalytic medium. The obtained model fits properly the experimental curves in the range of concentration, light intensity and air flow studied.

Performance of Nonconcentrating Solar Photocatalytic Oxidation Reactors: Part II—Shallow Pond Configuration

1994 ◽  
Vol 116 (1) ◽  
pp. 8-13 ◽  
Author(s):  
P. Wyness ◽  
J. F. Klausner ◽  
D. Y. Goswami ◽  
K. S. Schanze
Keyword(s):  
Photocatalytic Oxidation ◽  
Direct Evidence ◽  
Oxidation Process ◽  
Volume Ratio ◽  
Order Rate Constant ◽  
Solute Concentration ◽  
Catalyst Loading ◽  
Photocatalytic Process ◽  
Initial Concentration ◽  
First Order

A solar photocatalytic oxidation facility has been fabricated in which the destruction of 4-chlorophenol (4CP) is tested in three adjacent shallow pond reactors. Each of the reactors has depths of 5.1, 10.2, and 15.3 cm (2, 4, and 6 in.), respectively. It is found that 4CP is successfully oxidized with the photocatalyst, titanium dioxide (TiO2), suspended in a slurry or adhered to a fiberglass mesh. The pond reactors, however, perform better with the slurry. It has also been found that the first-order rate constant for oxidation of 4CP increases with decreasing initial concentration. For the same incident ultraviolet (UV) intensity, catalyst loading, and initial solute concentration, the oxidation rate of 4CP is invariant provided the aperture to volume ratio is fixed. It has been determined that the 4CP solution contains sufficient dissolved oxygen to support the photocatalytic oxidation process. Direct evidence is provided to demonstrate that the utilization of photons in the photocatalytic process becomes less efficient as the number of incident photons on the catalyst increases.

Aqueous Photocatalytic Oxidation of Doxycycline

2013 ◽  
Vol 16 (2) ◽  
Author(s):  
Deniss Klauson ◽  
Alissa Poljakova ◽  
Natalja Pronina ◽  
Marina Krichevskaya ◽  
Anna Moiseev ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Experimental Research ◽  
Photocatalytic Oxidation ◽  
Catalyst Concentration ◽  
Sol Gel ◽  
Fluidised Bed ◽  
Photocatalytic Reactor ◽  
Titania Coatings

AbstractThe experimental research into the aqueous photocatalytic oxidation of doxycycline, a tetracycline family antibiotic, was undertaken. The objective of the study was to ensure the feasibility of doxycycline photocatalytic degradation by UVA irradiated titania coatings on granulated media to be used in fluidised bed photocatalytic reactor and by slurries of P25, Evonik, as well as by visible light-sensitive sol-gel synthesized carbon-containing titania. The parameters influencing doxycycline oxidation, like catalyst concentration, initial doxycycline concentration and pH with P25 TiO

Photocatalytic degradation of explosives contaminated water

2002 ◽  
Vol 46 (11-12) ◽  
pp. 139-145 ◽  
Author(s):  
S.-J. Lee ◽  
H.-S. Son ◽  
H.-K. Lee ◽  
K.-D. Zoh
Keyword(s):  
Photocatalytic Degradation ◽  
Total Nitrogen ◽  
Contaminated Water ◽  
Ammonium Ions ◽  
Nitrate Ion ◽  
Photocatalytic Reactor ◽  
Initial Concentration ◽  
Initial Ph ◽  
Alkaline Conditions ◽  
The Impact

This study was undertaken to examine the degradation of TNT, RDX and HMX in a circular photocatalytic reactor with TiO2 as a photocatalyst. We examined the impact of parameters such as the initial concentration, initial pH of solution on rates of photocatalized transformation, and the mineralization. The results showed that photocatalysis is an effective process for the degradation of TNT, RDX and HMX. They could be completely degraded in 150 min with 1.0 g/L TiO2 at pH 7. An increase in the photocatalytic degradation of HMX was noticed with decreasing initial HMX. The rates of RDX and HMX degradation were greater in neutral pH than in acidic and alkaline conditions. In case of TNT degradation, the rate of degradation was the fastest at pH 11. Approximately 82% TOC decrease in the TNT degradation was achieved after 150 min, whereas TOC decrease in RDX and HMX was 24% and 59%, respectively. Nitrate, nitrite, and ammonium ions were detected as the nitrogen byproducts from the photocatalysis, and more than 50% of the total nitrogen was recovered as nitrate ion in every explosives.

scholarly journals PHOTOCATALYTIC SOLAR OXIDATION OF ACESULFAME-K. EFFECT OF INITIAL pH, CATALYST DOSE AND OXIDANT CONCENTRATION

2020 ◽  
Author(s):  
Julio César Morales Mejía ◽  
Karla Ibette Anselmo Cervantes ◽  
Iván García Mendoza ◽  
Rafael Almanza
Keyword(s):  
Concentration Ratio ◽  
Photocatalytic Oxidation ◽  
Research Work ◽  
Reaction Conditions ◽  
Photocatalytic Reactor ◽  
Initial Concentration ◽  
Oxidant Concentration ◽  
Initial Ph ◽  
Parabolic Collector ◽  
The Impact

Aqueous acesulfame-K was oxidized in a pilot solar photocatalytic reactor, equipped with a compound parabolic collector (CPC). The reactor has an area of 0.40 m2 of CPC collectors with geometrical concentration ratio of 1 and a simple mechanical configuration. The experiments of photocatalytic oxidation of acesulfame-K were performed by treating 2 L of water with an initial concentration of 15 mg/L. The photocatalyst used was P25 (Aeroxide TiO2) from Evonik. One of the goals of the research work was to find a set of conditions to efficiently remove this emerging concern pollutant. Results allowed proposing a set of reaction conditions that lead to a high removal of acesulfame-K. In addition, the experimental design allowed determining the effect of initial pH as well as the impact of initial concentrations of photocatalyst and chemical oxidant. The removal efficiency of acesulfame-K and related UV-absorbing species reached values up to 96-99 % and there was not a quantifiable amount of intermediate products (analyzed as UV absorbing species). Despite reaction time was fixed in 3 h for all the experiments, oxidation efficiencies higher than 95 % were reached at 2 h of reaction or even before.

scholarly journals PHOTOCATALYTIC SOLAR OXIDATION OF ACESULFAME-K. EFFECT OF INITIAL pH, CATALYST DOSE AND OXIDANT CONCENTRATION

2021 ◽  
Vol 37 ◽  
Author(s):  
Julio César Morales Mejía
Keyword(s):  
Concentration Ratio ◽  
Photocatalytic Oxidation ◽  
Research Work ◽  
Reaction Conditions ◽  
Photocatalytic Reactor ◽  
Initial Concentration ◽  
Oxidant Concentration ◽  
Initial Ph ◽  
Parabolic Collector ◽  
The Impact

Aqueous acesulfame-K was oxidized in a pilot solar photocatalytic reactor, equipped with a compound parabolic collector (CPC). The reactor has an area of 0.40 m2 of CPC collectors with geometrical concentration ratio of 1 and a simple mechanical configuration. The experiments of photocatalytic oxidation of acesulfame-K were performed by treating 2 L of water with an initial concentration of 15 mg/L. The photocatalyst used was P25 (Aeroxide TiO2) from Evonik. One of the goals of the research work was to find a set of conditions to efficiently remove this emerging concern pollutant. Results allowed proposing a set of reaction conditions that lead to a high removal of acesulfame-K. In addition, the experimental design allowed determining the effect of initial pH as well as the impact of initial concentrations of photocatalyst and chemical oxidant. The removal efficiency of acesulfame-K and related UV-absorbing species reached values up to 96-99 % and there was not a quantifiable amount of intermediate products (analyzed as UV absorbing species). Despite reaction time was fixed in 3 h for all the experiments, oxidation efficiencies higher than 95 % were reached at 2 h of reaction or even before.

Photocatalytic Degradation of Gaseous Acetone by a Self-Prepared Nano-Sized Composite TiO2/In2O3/SnO2 Film Photocatalyst

2011 ◽  
Vol 287-290 ◽  
pp. 1581-1584 ◽  
Author(s):  
Chung Shin Yuan ◽  
Hsieh Hung Tsai ◽  
Jeng Fong Wu ◽  
Bo Cheng Guo ◽  
Chung Hsuang Hung
Keyword(s):  
Surface Roughness ◽  
Photocatalytic Degradation ◽  
Blue Light ◽  
Double Layer ◽  
Reaction Rates ◽  
Experimental Results ◽  
Vacuum Pressure ◽  
Operating Parameters ◽  
Photocatalytic Reactor ◽  
Layer Film

The objective of this study is to decompose gaseous acetone ((CH3)2CO) by a self-prepared nano-sized composite TiO2/In2O3/SnO2 film photocatalyst that was prepared by a multi-target vacuum sputter operating at a vacuum pressure of 3 mtorr. The operating parameters investigated for the sputtering process included oxygen to argon ratio (O2/Ar), sputtering temperature, substrate materials, substrate layers, and sputtering duration. The nano-sized composite TiO2/In2O3/SnO2 film photocatalyst was mainly composed of anatase with a few rutile. The surface roughness of the TiO2/In2O3/SnO2 film photocatalyst in terms of RMS ranged from 2.292 to 7.533 nm, while the thickness of the single- and double-layer film photocatalysts were 473.5 and 506.0 nm, respectively. Gaseous acetone was initially injected into and further degraded in a self-designed batch photocatalytic reactor containing the nano-sized composite TiO2/In2O3/SnO2 film photocatalyst. Experimental results indicated that the highest acetone degradation efficiency of 99.9% was obtained at 50°C and 1 atm with the incident of near-UV illuminated by a fluorescent black light lamp. Under the incidence of blue light (430-500 nm), the reaction rates of acetone decomposition were 2.353x10-5 and 3.478x10-5 μmole/cm2-sec for using single- and double-layer TiO2/In2O3/SnO2 film photocatalysts, respectively.

A preliminary investigation on the photocatalytic degradation of a model humic acid

1996 ◽  
Vol 33 (6) ◽  
pp. 189-194 ◽  
Author(s):  
Miray Bekbölet ◽  
Gölhan Özkösemen
Keyword(s):  
Humic Acid ◽  
Photocatalytic Degradation ◽  
Acidic Medium ◽  
Photocatalytic Oxidation ◽  
Degradation Rate ◽  
Oxidation Process ◽  
Preliminary Investigation ◽  
Retardation Factor ◽  
Acid Solutions ◽  
Fluorescent Lamp

The research reported addresses the destructive removal of humic acid in aqueous medium by a photocatalytic oxidation process. Bench scale experiments were carried out using titanium dioxide as the photocatalyst and Black Light Fluorescent Lamp as the irradiation source. Following 1 h irradiation 40 % TOC and 75% Color400 removals were attained for 50 mg/L humic acid solution in the presence of 1.0 mg/mL TiO2. The optimum TiO2 loading was found to be 1.0 mg/mL. Acidic medium accelerated the photocatalytic degradation rate whereas a retardation factor of 0.4 was recorded in alkaline medium. The evaluation of the THMFPs of the photocatalytically treated humic acid solutions revealed that the destructive removal of humic acid was effective enough to keep the THM levels below the maximum contaminant level of 0.10 mg/L (USEPA).

UV photoelectrocatalytic degradation of m- cresol pollutant using TiO2 dip -coated stainless steel electrode system

2021 ◽  
pp. 123-131
Author(s):  
Jayabharathi Jayapal ◽  
M. Thenmozhi
Keyword(s):  
Stainless Steel ◽  
Kinetic Study ◽  
Photocatalytic Oxidation ◽  
Electrode System ◽  
Stainless Steel Electrode ◽  
Optimum Conditions ◽  
Steel Electrode ◽  
Initial Concentration ◽  
Photoelectrocatalytic Degradation ◽  
Uv Lamp

In the present study, the removal of m- cresol in an aqueous medium was studied by the photoelectrocatalytic (PEC) degradation by the TiO2 suspension on dip-coated stainless steel electrode under UV lamp of the wavelength of 352nm. The performance of the PEC method on the degradation of m- cresol was studied by made the comparison with the photocatalytic oxidation (PCO) method in terms of COD removal and kinetic study. In the PEC study on the degradation of m- cresol pollutant was studied by the various parameters such as initial concentration, pH, and the bias potential. The result found that the optimum degradation efficiency of m- cresol in the PEC and PCO methods were 79.6% and 39.8% at pH 5.0. The result showed that the kinetic constants (k) in the PEC and PCO methods were -0.0116 and -0.0058 under optimum conditions. The result found that the PEC method using TiO2 coated on stainless steel electrode is two times higher than the PCO method on the degradation of m- cresol.

scholarly journals Photocatalytic Degradation of Phenolics by N-Doped Mesoporous Titania under Solar Radiation

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Priti A. Mangrulkar ◽  
Sanjay P. Kamble ◽  
Meenal M. Joshi ◽  
Jyotsna S. Meshram ◽  
Nitin K. Labhsetwar ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Phenol Degradation ◽  
Catalyst Loading ◽  
Operating Parameters ◽  
Mesoporous Titania ◽  
Templating Method ◽  
Initial Concentration ◽  
Nitrogen Doped ◽  
Coexisting Ions

In this study, nitrogen-doped mesoporous titania was synthesized by templating method using chitosan. This biopolymer chitosan plays the dual role of acting as a template (which imparts mesoporosity) and precursor for nitrogen. BET-SA, XRD, UV-DRS, SEM, and FTIR were used to characterize the photocatalyst. The doping of nitrogen into TiO2lattice and its state was substantiated and measured by XPS. The photocatalytic activity of the prepared N-doped mesoporous titania for phenol ando-chlorophenol degradation was investigated under solar and artificial radiation. The rate of photocatalytic degradation was observed to be higher foro-chlorophenol than that of phenol. The photodegradation ofo-chlorophenol was 98.62% and 72.2%, while in case of phenol, degradation to the tune of 69.25% and 30.58% was achieved in solar and artificial radiation. The effect of various operating parameters, namely, catalyst loading, pH, initial concentration and the effect of coexisting ions on the rate of photocatalytic degradation were studied in detail.

Sign in / Sign up

Export Citation Format

Share Document